@article{doi101029jz070i016p03965, author = "Raleigh, C. B. and Paterson, Mike", title = "Experimental deformation of serpentinite and its tectonic implications", year = "1965", journal = "Journal of Geophysical Research Atmospheres", abstract = "Experimental investigation into the strength and ductility of serpentinite at temperatures to 700°C and confining pressures to 5 kb has yielded results important to the understanding of the role of serpentinite in orogenesis. Sealed specimens of antigorite-chrysotile serpentinite, with ultimate strength comparable to that of granite at room temperature, showed a marked weakening above 500–600°C; a mesh-textured serpentinite containing lizardite, chrysotile, and a minor amount of brucite showed a similar loss of strength at 300–350°C. Brittleness always accompanied the high-temperature weakening, although the samples showing high strength at lower temperatures were often ductile. Petrographic and X-ray examinations reveal that serpentine in the weakened and embrittled specimens has undergone partial dehydration to forsterite and talc. The embrittlement and weakening is attributed to a reduction in the effective confining pressure due to the pore pressure of the water released during dehydration and to a loss in cohesive strength due to changes in the structure upon dehydration. The hypothesis of tectonic emplacement of serpentinites of the alpine type thus becomes highly plausible at temperatures great enough for dehydration weakening, while being difficult to accept at lower temperatures where the strength of the serpentinite is high. Weakening upon heating to the appropriate dehydration temperature in the range 300–600°C of a partially serpentinized oceanic lower crust or upper mantle should also serve to concentrate deformation in the heated belt, thus facilitating mountain building. The embrittlement associated with dehydration extends the maximum theoretical depth for brittle fracture in the mantle to that of the deepest hydrated phases.", url = "https://doi.org/10.1029/jz070i016p03965", doi = "10.1029/jz070i016p03965", openalex = "W1963862763", references = "doi1010160022509653900192, doi1010160040195164900101, doi101029jz065i004p01083, doi101029jz066i007p02199, doi10108800319112218032, doi101126science1473655292, doi10113000167606195970115rofpim20co2, doi10113000167606195970167rofpim20co2, doi10113000167606196576469rofpim20co2, doi101306bc743a8716be11d78645000102c1865d" } @article{doi101038207343a0, author = "Wilson, J. Tuzo", title = "A New Class of Faults and their Bearing on Continental Drift", year = "1965", journal = "Nature", url = "https://doi.org/10.1038/207343a0", doi = "10.1038/207343a0", openalex = "W2054451772", references = "doi1010160025322764900489, doi101029jz068i021p05999, doi101038198925a0, doi101111j1365246x1964tb06303x, doi101111j216409471963tb01233x, doi101130001676061957681343gagsot20co2, doi101144gsjgs11410001, doi1023071781292, doi1023071783259, openalexw362631153" } @article{doi101029rg004i004p00509, author = "Hamilton, Warren and Myers, W. Bradley", title = "Cenozoic tectonics of the western United States", year = "1966", journal = "Reviews of Geophysics", abstract = "The Cenozoic structures of the western United States are interpreted here as being products mostly of horizontal motion of the crust. The distribution of strike‐slip faulting, tensional fragmentation of the brittle upper crust or rupturing of the entire continental crust, and compression define a pattern of northwestward motion increasing irregularly southwestward toward coastal California. Hans Becker, in 1934, and S. W. Carey, in 1958, are among those who have suggested such a tectonic system. The aggregate Cenozoic right‐lateral displacement of Cretaceous and older rocks and structures by the northwest‐trending strike‐slip faults of coastal California is about 500 km. The greater part of this movement has occurred along the San Andreas fault, but many other faults share in it. At least six earthquakes within the past century have been accompanied by lateral displacements at the surface along faults of the San Andreas system. Successively greater offsets of successively older geologic terranes demonstrate continuing motion throughout Cenozoic time. Late Miocene materials have been displaced at least 160 km; Oligocene, at least 260 km. The present velocity of regional shear strain, about 6 cm/yr, demonstrated by geodetic resurveying in southern and central California, is about 8 times faster than the average needed to account for the total movement within the Cenozoic. The faults are in general associated with structures formed by oblique tension south of Los Angeles and with structures due to oblique compression north of that city. The opening of the Gulf of California and the Salton Trough by the oblique rifting of Baja California and the Peninsular Ranges away from mainland Mexico is the greatest of the tensional effects. The strike‐slip faults may be confined to the crust. Earthquake foci extend no deeper than 16 km. The faults end to the south in the Gulf of California, whose crustal structure is oceanic. To the north, the San Andreas turns seaward as the north‐facing Gorda scarp, west in line of which in deeper water is the south‐facing Mendocino escarpment, produced apparently by an inactive left‐lateral oceanic fault. The continental sliver of coastal and Baja California, west of the faults of the San Andreas system, may be drifting northwestward independently over the ocean floor and the mantle, and the leading point of the sliver may have been deflected westward when it hit the Mendocino scarp on the sea floor. East of this coastal movement system is the Basin and Range province, whose obvious Cenozoic structures are dominated by block faulting. The present ranges have formed mostly since early Miocene time, similar older ranges having been destroyed by erosion and deformation. The normal faulting, which is not associated within the region with any complementary tectonic compression, requires crustal extension as its basic cause. If the faults maintain their average 60° dips at depth, extension is half the dip‐slip amount; but probably the major faults flatten downward, and the amount of extension about equals that of shallow dip‐slip. Total Cenozoic extension in northern Nevada and Utah may have been 300 km. Concurrent volcanism much augmented the thinned and fragmented crust, and the volcanic terranes in turn have been fragmented by block faulting. Right‐lateral strike‐slip faults trend northwestward in lanes between normal‐fault maintain blocks in the southwestern part of the Basin‐Range province. Cenozoic displacements reach 50 km on the Las Vegas fault and 80 km on the Death Valley‐Furnace Creek faults. Northeast of the strike‐slip faults, ranges and basins trend north‐northeastward in tension‐gash orientation. Within the belt of lateral faulting, ranges undergoing active normal faulting mostly trend north‐northwestward in oblique pull‐apart orientation. The Sierra Nevada and Klamath Mountains have moved northwestward and rotated counterclockwise, thus moving away from the continental interior more in the north than in the south, and the extension distributed behind them has formed the Basin‐Range province. The narrow block‐fault Rio Grande valley system of New Mexico and southern Colorado is structurally and topographically similar to the rift valleys of East Africa and reflects localized crustal extension. The Idaho batholith, like the Sierra Nevada batholith, is drifting northwestward as an unbroken plate. Extension east of the Idaho batholith is taken up by normal‐fault fragmentation in south‐central Idaho and southwestern Montana, whereas extension south of the batholith has produced a rift through the continental crust, the Snake River Plain, filled deeply by lava. Seismic velocities indicate granitic crust to be lacking in at least the western part of the plain. Right‐lateral faults of the Osburn system bound the batholithic plate on the north, and the motion they represent is taken up north of them by extension forming fault troughs. Integration of geologic and geophysical information shows that large regions of the Northwest are lava accumulations of continental crustal thickness, not old continental crust covered by lava. The volcanic terrane of northwestern Oregon and southwestern Washington forms new volcanic crust in a region which was oceanic before Cenozoic time. The volcanic terrane of southeastern Oregon, northeastern California, and northwestern Nevada fills an irregular tension rift through the Mesozoic continental crust. This rift resulted from the westward motion of the Klamath Mountains region, which was sundered from a position south of the Mesozoic terrane of northeastern Oregon and which was bent oroclinally as it moved westward in post‐middle Eocene time. The Mesozoic terrane of northeastern Oregon pivoted away from the Idaho batholith to form a smaller orocline and left a triangular rift since filled by lava. Independent motion of continental crust over mantle and oceanic crust seems to be indicated. Inertial forces due to redistribution of rotational momentum among crustal fragments, mantle, and core may provide the motive power.", url = "https://doi.org/10.1029/rg004i004p00509", doi = "10.1029/rg004i004p00509", openalex = "W1968113056", references = "doi1010160025322764900489, doi101029jz070i016p03965, doi1010970001069419660400000015, doi101126science1523721502, doi101130001676061965761145oordot20co2, doi10113000167606196677439pootcs20co2, doi101130spe71p1, doi101180minmag196503426832, doi101785bssa0470040353, doi105408002213687121, nicholls1965basalts, openalexw106656250" } @article{doi101029jb073i012p03661, author = "Pichon, Xavier Le", title = "Sea-floor spreading and continental drift", year = "1968", journal = "Journal of Geophysical Research Atmospheres", abstract = "A geometrical model of the surface of the earth is obtained in terms of rigid blocks in relative motion with respect to each other. With this model a simplified but complete and consistent picture of the global pattern of surface motion is given on the basis of data on sea-floor spreading. In particular, the vectors of differential movement in the ‘compressive’ belts are computed. An attempt is made to use this model to obtain a reconstruction of the history of spreading during the Cenozoic era. This history of spreading follows closely one previously advocated to explain the distribution of sediments in the oceans.", url = "https://doi.org/10.1029/jb073i012p03661", doi = "10.1029/jb073i012p03661", openalex = "W2138058376", references = "doi1010160025322764900489, doi101029jb073i006p01959, doi101029jb073i006p02119, doi101029jz072i008p02131, doi101029jz072i024p06261, doi101029rg004i004p00509, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi101126science15437531164, doi101126science15437551405, doi101130petrologic1962599, sykes1967mechanism" } @article{doi101029jb073i018p05855, author = "Isacks, Bryan L. and Oliver, Jack and Sykes, Lynn R.", title = "Seismology and the new global tectonics", year = "1968", journal = "Journal of Geophysical Research Atmospheres", abstract = "A comprehensive study of the observations of seismology provides widely based strong support for the new global tectonics which is founded on the hypotheses of continental drift, sea-floor spreading, transform faults, and underthrusting of the lithosphere at island arcs. Although further developments will be required to explain certain part of the seismological data, at present within the entire field of seismology there appear to be no serious obstacles to the new tectonics. Seismic phenomena are generally explained as the result of interactions and other processes at or near the edges of a few large mobile plates of lithosphere that spread apart at the ocean ridges where new surficial materials arise, slide past one another along the large strike-slip faults, and converge at the island arcs and arc-like structures where surficial materials descend. Study of world seismicity shows that most earthquakes are confined to narrow continuous belts that bound large stable areas. In the zones of divergence and strike-slip motion, the activity is moderate and shallow and consistent with the transform fault hypothesis; in the zones of convergence, activity is normally at shallow depths and includes intermediate and deep shocks that grossly define the present configuration of the down-going slabs of lithosphere. Seismic data on focal mechanisms give the relative direction of motion of adjoining plates of lithosphere throughout the active belts. The focal mechanisms of about a hundred widely distributed shocks give relative motions that agree remarkably well with Le Pichon's simplified model in which relative motions of six large, rigid blocks of lithosphere covering the entire earth were determined from magnetic and topographic data associated with the zones of divergence. In the zones of convergence the seismic data provide the only geophysical information on such movements. Two principal types of mechanisms are found for shallow earthquakes in island arcs: The extremely active zone of seismicity under the inner margin of the ocean trench is characterized by a predominance of thrust faulting, which is interpreted as the relative motion of two converging plates of lithosphere; a less active zone in the trench and on the outer wall of the trench is characterized by normal faulting and is thought to be a surficial manifestation of the abrupt bending of the down-going slab of lithosphere. Graben-like structures along the outer walls of trenches may provide a mechanism for including and transporting sediments to depth in quantities that may be very significant petrologically. Large volumes of sediments beneath the inner slopes of many trenches may correspond, at least in part, to sediments scraped from the crust and deformed in the thrusting. Simple underthrusting typical of the main zone of shallow earthquakes in island arcs does not, in general, persist at great depth. The most striking regularity in the mechanisms of intermediate and deep earthquakes in several arcs is the tendency of the compressional axis to parallel the local dip of the seismic zone. These events appear to reflect stresses in the relatively strong slab of down-going lithosphere, whereas shearing deformations parallel to the motion of the slab are presumably accommodated by flow or creep in the adjoining ductile parts of the mantle. Several different methods yield average rates of underthrusting as high as 5 to 15 cm/yr for some of the more active arcs. These rates suggest that temperatures low enough to permit dehydration of hydrous minerals and hence shear fracture may persist even to depths of 700 km. The thickness of the seismic zone in a part of the Tonga arc where very precise hypocentral locations are available is less than about 20 km for a wide range of depths. Lateral variations in thickness of the lithosphere seem to occur, and in some areas the lithosphere may not include a significant thickness of the uppermost mantle. The lengths of the deep seismic zones appear to be a measure of the amount of under thrusting during about the last 10 m.y. Hence, these lengths constitute another ‘yardstick’ for investigations of global tectonics. The presence of volcanism, the generation of many tsunamis (seismic sea waves), and the frequency of occurrence of large earthquakes also seem to be related to underthrusting or rates of underthrusting in island arcs. Many island arcs exhibit a secondary maximum in activity which varies considerably in depth among the various arcs. These depths appear, however, to correlate with the rate of underthrusting, and the deep maxima appear to be located near the leading (bottom) part of the down-going slab. In some cases the down-going plates appear to be contorted, possibly because they are encountering a more resistant layer in the mantle. The interaction of plates of lithosphere appears to be more complex when all the plates involved are continents or pieces of continents than when at least one plate is an oceanic plate. The new global tectonics suggests new approaches to a variety of topics in seismology including earthquake prediction, the detection and accurate location of seismic events, and the general problem of earth structure.", url = "https://doi.org/10.1029/jb073i018p05855", doi = "10.1029/jb073i018p05855", openalex = "W2043546840", references = "doi101029jb073i006p01959, doi101029jb073i006p02119, doi101029jb073i012p03661, doi101029jz070i016p03965, doi101029jz072i008p02131, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi1010382161276a0, doi101098rsta19650020, doi101126science15437531164, doi101126science15437551405, doi101130petrologic1962599, doi101785bssa0530010167, doi105408002213687121, sykes1967mechanism" } @article{doi1013065d25c4a516c111d78645000102c1865d, author = "Stöcklin, Jovan", title = "Structural History and Tectonics of Iran: A Review", year = "1968", journal = "AAPG Bulletin", abstract = "ABSTRACT The structural development of the Iranian ranges has certain peculiarities which contradict the conventional geosynclinal theory of mountain building. Early orogenic movements resulted in the consolidation of the Precambrian basement and the formation of a vast Iranian platform considered to be an extension of the Arabian shield. Only epeirogenic movements affected the region during the Paleozoic, which is represented by typical platform deposits. However, most of Iran went through all stages of a complete Alpine orogeny in spite of the prevailing platform character in preorogenic time. Important trends in the Alpine structural plan clearly were inherited from Precambrian structures. Precursory Alpine movements in Mesozoic time were strongest in Central Iran, although this region and the closely related Alborz (Elburz) Mountain area generally retained their epicontinental character, allowing for only a rudimentary geosynclinal development. More clearly geosynclinal conditions developed in peripheral fold belts: the Zagros, the Kopet Dagh, and the East Iranian ranges. Strong folding and thrusting during the Alpine orogeny proper in Late Cretaceous-Tertiary time affected most of Iran except the rigid Lut block in the eastern part of the country. The conventional tripartite division of Iran into an extensive median mass and two bordering ranges of geosynclinal origin (Zagros, Alborz) cannot be maintained. The writer replaces this oversimplified interpretation by recognizing the existence of more structural zones which differ in structural development and present tectonic style.", url = "https://doi.org/10.1306/5d25c4a5-16c1-11d7-8645000102c1865d", doi = "10.1306/5d25c4a5-16c1-11d7-8645000102c1865d", openalex = "W1993744042", references = "doi1023071794401" } @article{doi101130001676061969801639totcam20co2, author = "Molnár, Péter and Sykes, Lynn R.", title = "Tectonics of the Caribbean and Middle America Regions from Focal Mechanisms and Seismicity", year = "1969", journal = "Geological Society of America Bulletin", abstract = "Seismic data strongly support recent theories of tectonics in which large plates of lithosphere move coherently with respect to one another as nearly rigid bodies, spreading apart at ocean ridges, sliding past one another at transform faults, and underthrusting at island arcs. Boundaries between adjacent plates of lithosphere are defined by belts of high seismic activity. Redetermination of more than 600 hypocenters in the Middle America region and previous studies in the Galapagos and Caribbean regions define the boundaries of two relatively small, nearly aseismic plates in the region of interest. The first, the Cocos plate, is bordered by the East Pacific rise, the Galapagos rift zone, the north-trending Panama fracture zone near 82° W., and the Middle America arc; the second, the Caribbean plate, underlies the Caribbean Sea and is bounded by the Middle America arc, the Cayman trough, the West Indies arc, and the seismic zone through northern South America. Focal mechanisms of 70 earthquakes in these regions were determined to ascertain the relative motion of these two plates with respect to the surrounding regions or plates. The results show underthrusting of the Cocos plate beneath Mexico and Guatemala in a northeasterly direction and beneath the rest of Central America in a more north-northeasterly direction. The Cocos plate is spreading away from the rest of the Pacific floor at the East Pacific rise and at the Galapagos rift zone. Motion is right-lateral strike-slip along the Panama fracture zone, a transform fault connecting the Galapagos rift zone and the Middle America arc. At the same time, the Caribbean plate is moving easterly with respect to the Americas plate, which is here taken to include both North and South America and the western Atlantic. Left-lateral strike-slip motion along steeply dipping fault planes is observed on the Cayman trough. The Americas plate is underthrusting the Caribbean in a westerly direction at the Lesser Antilles and near Puerto Rico. Unlike the Lesser Antilles, however, motion at present is not perpendicular to the Puerto Rico trench but instead is almost parallel to the trench along nearly horizontal fault planes. Computations of rates of motion indicate that underthrusting is at a higher rate in southeastern Mexico and Guatemala than in western Mexico and that the Caribbean is moving at a lower rate relative to North America than is the Cocos plate.", url = "https://doi.org/10.1130/0016-7606(1969)80[1639:totcam]2.0.co;2", doi = "10.1130/0016-7606(1969)80[1639:totcam]2.0.co;2", openalex = "W1991156767" } @article{doi101029jb075i014p02625, author = "Dewey, John and Bird, John", title = "Mountain belts and the new global tectonics", year = "1970", journal = "Journal of Geophysical Research Atmospheres", abstract = "Analysis of the sedimentary, volcanic, structural, and metamorphic chronology in mountain belts, and consideration of the implications of the new global tectonics (plate tectonics), strongly indicate that mountain belts are a consequence of plate evolution. It is proposed that mountain belts develop by the deformation and metamorphism of the sedimentary and volcanic assemblages of Atlantic-type continental margins. These assemblages result from the events associated with the rupture of continents and the expansion of oceans by lithosphere plate generation at oceanic ridges. The earliest assemblages thus developed are volcanic rocks and coarse clastic sediments deposited in fault-bounded troughs on a distending and segmenting continental crust, subsequently split apart and carried away from the ridge on essentially aseismic continental margins. As the continental margins move away from the ridge, nonvolcanic continental shelf and rise assemblages of orthoquartzite-carbonate, and lutite (shelf), and lutite, slump deposits, and turbidites (rise) accumulate. This kind of continental margin is transformed into an orogenic belt in one of two ways. If a trench develops near, or at, the continenal margin to consume lithosphere from the oceanic side, a mountain belt (cordilleran type) grows by dominantly thermal mechanisms related to the rise of calc-alkaline and basaltic magmas. Cordilleran-type mountain belts are characterized by paired metamorphic belts (blueschist on the oceanic side and high temperature on the continental side) and divergent thrusting and synorogenic sediment transport from the high-temperature volcanic axis. If the continental margin collides with an island arc, or with another continent, a collision-type mountain belt develops by dominantly mechanical processes. Where a continent/island arc collision occurs, the resulting mountains will be small (e.g., the Tertiary fold belt of northern New Guinea), and a new trench will develop on the oceanic side of the arc. Where a continent/continent collision occurs, the mountains will be large (e.g., the Himalayas), and the single trench zone of plate consumption is replaced by a wide zone of deformation. Collision-type mountain belts do not have paired metamorphic belts; they are characterized by a single dominant direction of thrusting and synorogenic sediment transport, away from the site of the trench over the underthrust plate. Stratigraphic sequences of mountain belts (geosynclinal sequences) match those asciated with present-day oceans, island arcs, and continental margins.", url = "https://doi.org/10.1029/jb075i014p02625", doi = "10.1029/jb075i014p02625", openalex = "W2111555634", references = "doi101007bf02597153, doi101029jb073i006p01959, doi101029jb073i012p03661, doi101029jb073i018p05855, doi101038211676a0, doi1010382161276a0, doi101093petrology23277, doi101111j1365246x1969tb00259x, doi101130001676061969802409mcatuo20co2, doi1013065d25c4a516c111d78645000102c1865d, doi101785bssa0590010369" } @article{doi101029rg008i004p00813, author = "Dickinson, William R.", title = "Relations of andesites, granites, and derivative sandstones to arc‐Trench tectonics", year = "1970", journal = "Reviews of Geophysics", abstract = "Andesitic volcanogenic sequences, granitic batholith belts, and derivative graywacke‐arkose sedimentary successions are prominent rock assemblages associated with alpinotype peridotite‐gabbro belts and other characteristic tectonic features in orogenic regions or mobile belts where repeated crustal deformation and metamorphism have occurred. Field relations in the circum‐Pacific region indicate that andesitic eruptive suites and granitic intrusive suites are commonly consanguineous and roughly contemporaneous and that they have shed voluminous detritus into coeval graywacke‐arkose belts nearby. Modern systems of oceanic trenches and parallel magmatic arcs are probable analogues of the tectonic settings in which the three related rock assemblages formed. Data on crustal geophysics, trace‐element geochemistry, and strontium‐isotope ratios preclude participation of sialic crust in the generation of andesitic magmas at shallow levels but permit alternative hypotheses of primary partial melts from the mantle, derivative melts differentiated from primary basaltic melts, or melts from oceanic lithosphere slabs descending along inclined seismic zones beneath the volcanic arcs. In Quaternary andesitic suites, areal petrologic variations, particularly in potash content, are consistent tranverse to active volcanic chains regardless of longitudinal variations in crustal thickness. Levels of potash content in different suites correlate well with depths to the inclined seismic zone beneath, although significant scatter of points is apparent. Petrologic data from older andesitic terranes can be used to plot approximate positions and inclinations of paleoseismic zones. The anatectic hypothesis for the origin of magmatic plutons in intrusive batholiths is challenged by apparent comagmatic associations with andesitic eruptives, common sequences of intrusion from mafic to felsic, doubtful presence of suitable geosynclinal roots in some areas, available strontium‐isotope ratios, difficult geothermal inferences, and unexpected episodicity or periodicity of repeated intrusive events that are correlative throughout large longitudinal segments of batholith belts. Consistent positions of batholith belts along the trends of relatively high‐temperature and low‐pressure members of paired metamorphic belts suggest that the granitic plutons were emplaced in the roots of complex volcanoplutonic arcs, and that granitic intrusive magmas may be derived from the same deep sources as andesitic eruptive magmas. Transverse petrologic asymmetry within Mesozoic batholiths of western North America is reminiscent of the similar petrologic asymmetry within Cenozoic volcanic terranes, and may be used to construct speculative paleoseismic zones for the volcanoplutonic arcs whose roots the batholiths may represent. Graywacke and arkose sequences that lie on the Pacific side of andesitic volcanogenic and granitic batholith belts are composed mainly of first‐cycle volcanic and plutonic detritus and commonly form large parts of the relatively low‐temperature and high‐pressure members of paired metamorphic belts. Detritus eroded during and between successive episodes of volcanism and plutonism in the adjacent volcano‐plutonic provenances was deposited in parallel subsiding belts, where it was progressively buried as an inverse record of the successive magmatic increments to the arc regions. The graywacke‐arkose belts commonly include two parallel divisions. Distal facies of strongly deformed trench and continental‐rise deposits were ground against and beneath the seaward flanks of the volcanoplutonic arcs. Proximal facies of more orderly strata were deposited in sediment traps between trenches and arcs in the tectonic position occupied by shelves, slopes, and troughs of varied bathymetric character in modern arc‐trench systems. The interpretations in this paper attempt to bring petrologic inferences about orogenic rock assemblages in line with current mobilist tectonic concepts that are supplanting previous stabilist views. The formation of the three rock assemblages discussed is probably the principal means by which continental crust is formed from the mantle.", url = "https://doi.org/10.1029/rg008i004p00813", doi = "10.1029/rg008i004p00813", openalex = "W1982637387", references = "doi101029rg004i004p00509, doi101093petrology12121, doi101126science1633864237, doi10130674d720182b2111d78648000102c1865d" } @article{doi101038235147a0, author = "Takin, Manoochehr", title = "Iranian Geology and Continental Drift in the Middle East", year = "1972", journal = "Nature", url = "https://doi.org/10.1038/235147a0", doi = "10.1038/235147a0", openalex = "W2039609237", references = "doi101038225139a0" } @article{doi101111j1365246x1972tb02351x, author = "McKenzie, Dan", title = "Active Tectonics of the Mediterranean Region", year = "1972", journal = "Geophysical Journal International", abstract = "Examination of more than 100 fault plane solutions for earthquakes within the Alpide belt between the Mid-Atlantic ridge and Eastern Iran shows that the deformation at present occurring is the result of small continental plates moving away from Eastern Turkey and Western Iran. This pattern of movement avoids thickening the continental crust over much of Turkey by consuming the Eastern Mediterranean sea floor instead. The rates of relative motion of two of the small plates involved, the Aegean and the Turkish plates, are estimated, but are only within perhaps 50 per cent of the true values. These estimates are then used to reconstruct the geometry of the Mediterranean 10 million years ago. The principal difference from the present geometry is the smooth curved coast which then formed the southern coast of Yugoslavia, Greece and Turkey. This coast has since been distorted by the motion of the two small plates. Similar complications have probably been common in older mountain belts, and therefore local geological features may not have been formed by the motion between major plates.", url = "https://doi.org/10.1111/j.1365-246x.1972.tb02351.x", doi = "10.1111/j.1365-246x.1972.tb02351.x", openalex = "W2155472085", references = "doi101029jb073i012p03661, doi101029jb073i018p05855, doi101029jz072i008p02131, doi101029rg009i001p00103, doi101038207343a0, doi1010382161276a0, doi101038224125a0, doi101038226239a0, doi101111j1365246x1969tb00259x, doi101111j1365246x1971tb02190x, doi10113000167606196071843peotca20co2, doi101144transed83387, doi101785bssa0590010369, sykes1967mechanism" } @article{meyerhoff1972continental2, author = "Meyerhoff, A. A. and Meyerhoff, H. A. and Briggs, R. S", title = "Continental drift, V", year = "1972", journal = "Journal of Geology, v. 80, p. 663-692", note = "talkorigins\_source = {true}; raw\_reference = {Meyerhoff, A. A., Meyerhoff, H. A., and Briggs, R. S., 1972, Continental drift, V: Journal of Geology, v. 80, p. 663-692.}" } @techreport{meyerhoff1972the1, author = "Meyerhoff, A. A. and Meyerhoff, H. A", title = "The new global tectonics", year = "1972", howpublished = "Age of linear magnetic anomalies of ocean basins: Bulletin of the American Association of Petroleum Geologists, v. 56, p. 337-359", note = {talkorigins\_source = {true}; raw\_reference = {Meyerhoff, A. A., and Meyerhoff, H. A., 1972, "The new global tectonics": Age of linear magnetic anomalies of ocean basins: Bulletin of the American Association of Petroleum Geologists, v. 56, p. 337-359.}} } @article{doi101086627882, author = "Burke, Kevin and Dewey, John", title = "Plume-Generated Triple Junctions: Key Indicators in Applying Plate Tectonics to Old Rocks", year = "1973", journal = "The Journal of Geology", abstract = "Continental lithosphere-especially where stationary with respect to mantle plumes-is marked by plume-generated uplifts typically crested by volcanoes that rupture in three rifts at angles of about 120° to each other, perhaps because this configuration requires the least work. It is proposed that since the plate tectonic regime began, about years B.P., divergent plate motion has commonly begun at axial dikes emplaced in rifts formed in this way. A normal course of events is that two of the rifts meeting at a junction to open by plate accretion while the third rift becomes inactive as a failed arm. The evolution of 45 selected junctions, with ages ranging back to years B.P., illustrates a variety of ways in which triple junctions may develop. Bends in rifted Atlantic-type continental margins reflect the distribution of triple junctions at the time continents parted and plume traces on ocean floors lead away from these former triple junctions. Where oceans have closed by continental collision, rifts (failed arms) (aulacogens of Soviet authors), striking at high angles into orogenic belts, mark the location of former triple junctions. Reactivation of old rifts is common and new rifts have frequently developed on the sutures along which oceans have closed. Base metal mineralization, especially in the form of syngenetic copper ores, is a feature of some failed arms (Montana, Zambia, Coppermine) and others, which contain up to 10 km of marine sediment, possess some of the world's major petroleum deposits (Northern North Sea, Niger Delta, Gippsland Basin, Gulf of Suez, and Gulf of Sirte). Many of the world's great rivers flow down failed arms (Mississippi, Amazon, Niger, Zambezi, Limpopo, Rhine).", url = "https://doi.org/10.1086/627882", doi = "10.1086/627882", openalex = "W1979331501", references = "doi101029jb076i014p03179, doi101038211676a0, doi101038224125a0, doi101098rsta19650020, doi101111j1365246x1971tb02190x, doi10113000167606197283619ssitna20co2" } @article{doi101086627920, author = "Dewey, John and Burke, Kevin", title = "Tibetan, Variscan, and Precambrian Basement Reactivation: Products of Continental Collision", year = "1973", journal = "The Journal of Geology", abstract = "Extensive terranes of basement reactivation are interpreted as resulting from crustal thickening following continental collision. It is suggested that terranes, such as the Grenville Province and much of the Variscan orogenic belt in Europe, have their modern analog in the Tibetan Plateau. The Tibetan Plateau is underlain by a continental crust between 60 and 80 km thick and is characterized by extensive high-potash Neogene vulcanism. Following T. H. Green's arguments that partial melting of a dioritic lower crust may yield potassic granitic liquids and refractory anorthositic residues, we consider that continental collision is followed by crustal thickening, to accommodate further plate convergence, with ensuing partial melting of the lower crust. At high structural levels, silicic-potassic ignimbrites are extruded in intermontane basin-horst terranes, with subjacent granite plutons. At deeper levels, a dry refractory lower crust consisting of pyroxene granulites and anor-thosites is generated.", url = "https://doi.org/10.1086/627920", doi = "10.1086/627920", openalex = "W2093671367" } @article{doi1023071796560, author = "Steers, J. A. and Tarling, D. H. and Runcorn, S. K.", title = "Implications of Continental Drift to the Earth Sciences", year = "1974", journal = "Geographical Journal", abstract = "Quantitative geophysical evidence for the reality of continental drift was first obtained from the comparison of palaeomagnetic directions in igneous and sedimentary rocks from different continents. More recently Wegeners concept of continental drift has been beautifully complimented by the hypothesis of sea-floor spreading. Again the palaeomagnetism of the ocean floor has provided quantitative evidence for its occurrence. Thus the older qualitative arguments from the geological record, presented so imaginatively by Alfred Wegener, have been vindicated. In recent years we have seen a marked change in the climate of scientific opinion about the reality of major horizontal movements of parts of the Earths surface and, from palaeomagnetic and other geophysical studies, the positions of the continents in different geological periods and the evolution of the ocean basins are being determined. It is still not very clear how these movements take place in time and there is still considerable uncertainty about the precise relationships of different parts of the Earth's surface during the geological past. These developments have, however, essentially ended the long debate about whether or not the classical lines of geological evidence, palaeoclimatic, palaeontological distributions, global tectonic patterns and lithological relationships, support or refute drift. What is now scientifically significant is the study of the geological record in the light of the known horizontal displacements. This is of great potential importance to various other sciences involved in the study of our environment, e.g. biology, global meteorology. These two volumes are the proceedings of the April 1972 NATO Advanced Study Institute held in the University of Newcastle upon Tyne. They commence mainly with reviews of the objective evidence for the past position of the continents, i.e. the palaeomagnetism of continental and oceanic rocks. The palaeontological evidence is then examined to see how the creation of supercontinents and their fragmentation affects the mobility and rate of evolution of the biota on and around them. This data must also be examined carefully in order to delineate evidence which still appears inconsistent with current views of the past distribution of the continents to see if our presentviews need modification or whether such discrepancies can yield further information about our planet in the past, for example, the distribution of topographic, predatory or climatic barriers to the migration of terrestrial fauna. Similarly, the movement of continental fragments into different climatic belts obviously has an effect on their prevailing climate, but this movement, particularly the formation or fragmentation of supercontinents, must also hope a drastic effect on the climatic belts themselves.", url = "https://doi.org/10.2307/1796560", doi = "10.2307/1796560", openalex = "W2020499116" } @article{doi101126science1894201419, author = "Molnár, Péter and Tapponnier, P.", title = "Cenozoic Tectonics of Asia: Effects of a Continental Collision: Features of recent continental tectonics in Asia can be interpreted as results of the India-Eurasia collision", year = "1975", journal = "Science", url = "https://doi.org/10.1126/science.189.4201.419", doi = "10.1126/science.189.4201.419", openalex = "W2002325302", references = "doi101029jb073i006p02119, doi101029jb073i018p05855, doi101029jb075i014p02625, doi101029jb078i032p07675, doi101086627920, doi101093oso97801985036750010001, doi101111j1365246x1969tb00259x, doi101111j1365246x1972tb02351x, doi101111j1365246x1974tb00613x, doi10113000167606197283619ssitna20co2, powell1973plate" } @article{doi101029rg016i004p00621, author = "Sykes, Lynn R.", title = "Intraplate seismicity, reactivation of preexisting zones of weakness, alkaline magmatism, and other tectonism postdating continental fragmentation", year = "1978", journal = "Reviews of Geophysics", abstract = "The distribution of intraplate earthquakes and of igneous rocks postdating continental rifting is summarized and placed into a plate tectonic framework for the following continental areas: eastern and central North America, Africa, Australia, Brazil, Greenland, Antarctica, Norway, Spitsbergen, India, and the margins of the Red Sea and Gulf of Aden. In continents, intraplate earthquakes tend to be concentrated along preexisting zones of weakness within areas affected by the youngest major orogenesis that predates the opening of the present oceans. Many preexisting zones of weakness (including fault zones, suture zones, failed rifts, and other tectonic boundaries), particularly those near continental margins, were reactivated during the early stages of continental separation. In contrast, intraplate shocks rarely occur within the older oceanic lithosphere or within the interiors of ancient cratonic blocks of the continents. In several continental areas, rocks and tectonic features postdating the opening of present‐day oceans, including carbonatites, kimberlites, other alkalic rocks, mafic dikes, and ring dikes, as well as some of the largest intraplate shocks, seem to be located preferentially along old zones of weakness near the ends of major oceanic transform faults that were active in the early opening of adjacent oceans. In several places, alkaline magmatism and earthquakes extend several hundred kilometers inland from the ends of oceanic transform faults (but not necessarily with the same strike as the transform fault). Major preexisting zones of weakness that are oriented subparallel to the directions of relative continental separation appear to control the locations of transform faults that develop in a new ocean. In some instances, alkaline magmatism persisted along reactivated features of this type for as long as 100 m.y. after the initial stages of continental fragmentation. Most kimberlites in South Africa seem to have been emplaced along preexisting zones of weakness that were reactivated during the early opening of the South Atlantic. The type of intraplate magmatism appears to be related to the thickness of the lithosphere. Unlike oceanic transform faults where large horizontal movements have occurred, reactivated zones of weakness in continents usually appear to have been the sites of only relatively small displacement. Seismic activity and alkaline magmatism may be controlled by deep fractures that penetrated the entire lithosphere to tap asthenospheric sources of magma. Seismic activity along these zones seems to occur in response to the present‐day stress regime, which is not necessarily the same as that which was active during the emplacement of the alkaline rocks. Other intraplate shocks are concentrated along old zones of weakness that are subparallel to continental margins. Such shocks are found in the Appalachians, northeastern and northern Greenland, Norway, Great Britain, Spitsbergen, northern Canada, and Australia. These zones of weakness were also reactivated during continental separation in either the Mesozoic or the Cenozoic. Evidence is now mounting for Cretaceous and Cenozoic deformation along some of these features. Although not many focal mechanism solutions or in situ measurements of stress are available for intraplate areas, horizontal compressive stresses appear to be present today in many of the pre‐Mesozoic orogenic belts that were reactivated by continental rifting. This evidence, as well as examples of Cenozoic thrust faulting, indicates that the stress field has changed since rifting commenced. High compressive stresses, the absence of earthquakes in Antarctica, their near absence along the margins of the Gulf of Mexico, and the much lower levels of activity in the oceanic lithosphere adjacent to most continents argue against mere sedimentary loading and the cooling of the oceanic lithosphere as the main source of stress that is reactivating faults of these older fold belts. The large compressive stresses and the uplift found in many continental areas adjacent to continental margins may be caused by a deep‐seated source in the mantle of long wavelength or by stresses transmitted in the lithosphere. These effects may be related to either the cooling and underplating of the continental lithosphere adjacent to continental margins, large tractions on the base of the lithosphere in shield areas, stress concentrations related to marked changes in the age and thickness of the lithosphere, convective motions of the mantle beneath these areas, or those regions acting like broad zones of weakness that are being compressed between adjacent areas of greater strength. During the fragmentation of a supercontinent, multibranched rifting usually follows the youngest zone of previous orogenesis and as much as possible avoids passing through old cratonic areas where the lithosphere is thick, cold, and strong. Rift junctions seem to be related to the preexisting mosaic of cratons and younger belts of deformation rather than to a motive force involving mantle plumes. Likewise, many zones of unusually high magmatic activity, i.e., hot spots, appear to be related to nodes or junctions in this mosaic pattern. Thus these hot spots appear to be passive features rather than the surficial expression of mantle plumes. Major transform faults that are active during the early opening of an ocean also tend to develop where the margins of the older cratons undergo an abrupt change in strike. During the early development of an ocean the preexisting mosaic of structural elements within the thick continental lithosphere may result in large normal forces across some plate margins, leaky transform faulting, and localized stress concentrations. The early directions of sea floor spreading and of transforming faulting may be altered by these boundary forces and by the geometrical constraints imposed in separating old cratonic blocks. These constraints are relaxed once old, thick lithosphere is no longer in contact across long transform faults. Since these early directions are strongly influenced by the preexisting tectonic framework and may not coincide with the direction of the forces driving the plates apart, early transform faults may have components of extension (or compression) along them in addition to strike slip motion. A small component of extension may be responsible for the formation of volcanic ridges and seamount chains such as the Walvis ridge, Rio Grande rise, and New England seamount chain. These features predate the marked change in the strike of transform faulting that occurred in the North and South Atlantic about 80 m.y. ago as thin oceanic lithosphere finally came in contact across large oceanic transform faults. Several zones of intraplate magmatism in the surrounding continents also ceased at that time.", url = "https://doi.org/10.1029/rg016i004p00621", doi = "10.1029/rg016i004p00621", openalex = "W1983992782", references = "doi1010160040195168900590, doi101038207343a0, doi101038211676a0, doi101086627882, doi101111j1365246x1974tb00613x, doi101126science1894201419, doi10113000167606197283619ssitna20co2, doi101130001676061973843137ptateo20co2, doi1011300091761319742377ptmfte20co2, doi1023071796560, doi105408002213687121, openalexw630270902" } @article{doi101111j1365246x1978tb04759x, author = "McKenzie, Dan", title = "Active tectonics of the Alpine--Himalayan belt: the Aegean Sea and surrounding regions", year = "1978", journal = "Geophysical Journal International", abstract = "New fault plane solutions, Landsat photographs, and seismic refraction records show that rapid extension is now taking place in the northern and eastern parts of the Aegean sea region. The southern part of the Aegean has also been deformed by normal faulting but is now relatively inactive. In northwestern Greece and Albania there is a band of thrusting near the western coasts adjacent to a band of normal faulting further east. The pre-Miocene geology of the islands in the Aegean closely resembles that of Greece and Turkey, yet seismic refraction shows that the crust is now only about 30 km thick beneath the southern part of the sea, compared with nearly 50 km beneath Greece and western Turkey. These observations suggest that the Aegean has been stretched by a factor of two since the Miocene. This stretching can account for the high heat flow. The sinking slab produced by subduction along the Hellenic Arc may maintain the motions, though the geometry and widespread nature of the normal faulting is not easily explained. The motions in northwestern Greece and Albania cannot be driven in the same way because no slab exists in the area. They may be maintained by blobs of cold mantle detaching from the lower half of the lithosphere, produced by a thermal instability when the lithosphere is thickened by thrusting. Hence generation and destruction of the lower part of the lithosphere may occur beneath deforming continental crust without the production of any oceanic crust.", url = "https://doi.org/10.1111/j.1365-246x.1978.tb04759.x", doi = "10.1111/j.1365-246x.1978.tb04759.x", openalex = "W2048403692", references = "doi101038226239a0, doi101111j1365246x1969tb00259x" } @article{doi101126science20043451003, author = "McCulloch, Malcolm T. and Wasserburg, G. J.", title = "Sm-Nd and Rb-Sr Chronology of Continental Crust Formation", year = "1978", journal = "Science", abstract = "Samarium-neodymium and rubidium-strontium isotopic systematics together with plausible assumptions regarding the geochemical evlution of continental crust material, have been used to ascertain the times at which segments of continental crust were formed. Analyses of composites from the Canadian Shield representing portions of the Superior, Slave, and Churchill structural provinces indicate that these provinces were all formed within the period 2.5 to 2.7 aeons. It has been possible to determine the mean age of sediment provenances, as studies of sedimentary rocks suggest that the samarium-neodymium isotopic system is not substantially disturbed during sedimentation or diagenesis.", url = "https://doi.org/10.1126/science.200.4345.1003", doi = "10.1126/science.200.4345.1003", openalex = "W2057091716", references = "doi1010160016703769901537, doi1010160016703776900934, doi10113000167606196576803masord20co2" } @article{doi101029jb084ib13p07561, author = "Bird, Peter", title = "Continental delamination and the Colorado Plateau", year = "1979", journal = "Journal of Geophysical Research Atmospheres", abstract = "Continental lithosphere is in unstable mechanical equilibrium because its mantle layer is denser than the asthenosphere. If any process such as cracking, slumping, or plume erosion initially provided an elongated conduit connecting the underlying asthenosphere with the base of the continental crust, the dense lithospheric boundary layer could peel away from the crust and sink. An analytic model for sinking velocities at the critical initial time shows that instability occurs if the effective viscosities of the lower continental crust and the rising asthenosphere are no more than 10 19 P. Analogies to subduction suggest that the mature instability would grow laterally at plate tectonic velocities; however, it would be almost aseismic. Loss of the cold mantle boundary layer would cause uplift, increased heat flow, reduced seismic velocities, and perhaps emplacement of basalt flows, mantle diatremes, and granodiorite sills. A one‐dimensional thermal model of the formation of a new boundary layer predicts a half life of about 3×10 7 years for this thermal anomaly and uplift. As an example, the geologic and geophysical data from the Colorado Plateau are shown to be consistent with the hypothesis that it was uplifted by a delamination event 30 m.y. ago and perhaps a second event about 5 m.y. ago.", url = "https://doi.org/10.1029/jb084ib13p07561", doi = "10.1029/jb084ib13p07561", openalex = "W2078181124", references = "doi101007bf00388953, doi1010160012825272900384, doi1010160040195178901403, doi101029jb075i020p03941, doi101029jb082i036p05705, doi101029jb083ib10p04975, doi101029jb083ib11p05331, doi101029jz064i010p01521, doi101029me001p0259, doi101111j1365246x1975tb00631x, doi101130001676061974851225somfam20co2" } @article{doi1013062f9188fb16ce11d78645000102c1865d, author = "Dickinson, William R. and Suczek, Christopher A.", title = "Plate Tectonics and Sandstone Compositions", year = "1979", journal = "AAPG Bulletin", abstract = "Abstract Detrital framework modes of sandstone suites from different kinds of basins are a function of provenance types governed by plate tectonics. Quartzose sands from continental cratons are widespread within interior basins, platform successions, miogeoclinal wedges, and opening ocean basins. Arkosic sands from uplifted basement blocks are present locally in rift troughs and in wrench basins related to transform ruptures. Volcaniclastic lithic sands and more complex volcano-plutonic sands derived from magmatic arcs are present in trenches, forearc basins, and marginal seas. Recycled orogenic sands, rich in quartz or chert plus other lithic fragments and derived from subduction complexes, collision orogens, and foreland uplifts, are present in closing ocean basins, diverse successor basins, and foreland basins. Triangular diagrams showing framework proportions of quartz, the two feldspars, polycrystalline quartzose lithics, and unstable lithics of volcanic and sedimentary parentage successfully distinguish the key provenance types. Relations between provenance and basin are Important for hydrocarbon exploration because sand frameworks of contrasting detrital compositions respond differently to diagenesis, and thus display different trends of porosity reduction with depth of burial.", url = "https://doi.org/10.1306/2f9188fb-16ce-11d7-8645000102c1865d", doi = "10.1306/2f9188fb-16ce-11d7-8645000102c1865d", openalex = "W2023601146", references = "doi10113000167606197586273hmffdi20co2, doi10130674d720182b2111d78648000102c1865d, openalexw2094255421" } @article{doi101139e81019, author = "Berberian, Manuel and King, G. C. P.", title = "Towards a paleogeography and tectonic evolution of Iran", year = "1981", journal = "Canadian Journal of Earth Sciences", abstract = "Maps of the paleography of Iran are presented to summarize and review the geological evolution of the Iranian region since late Precambrian time. On the basis of the data presented in this way reconstructions of the region have been prepared that take account of the known major movements of continental masses. These reconstructions, which appear at the beginning of the paper, show some striking features, many of which were poorly appreciated previously in the evolution of the region. They include the closing of the 'Hercynian Ocean' by the northward motion of the Central Iranian continental fragment(s), the apparently simultaneous opening of a new ocean ('the High-Zagros Alpine Ocean') south of Iran, and the formation of 'small rift zones of oceanic character' together with the attenuation of continental crust in Central Iran.With the disappearance of the Hercynian Ocean, the floor of the High-Zagros Alpine Ocean started to subduct beneath southern Central Iran and apparently disappeared by Late Cretaceous – Early Paleocene time (65 Ma). From this time the compressional motion between Arabia and Eurasia has been accommodated in Iran by shortening and thickening of the continental crust. This crustal thickening is accompanied by a progressive, though eventful, transition from marine to continental conditions over the whole region.A striking feature highlighted in this study is the existence of extensive alkaline and calc-alkaline volcanics, which appear to be unrelated to subduction. The intrusion of these rocks started in Middle Eocene time (45 Ma) and extended to the present. It is clear that some major fault systems have played a continuous but varied role from the Precambrian until the present, and whatever controlled the original fold orientation at the onset of continental compression (65 Ma) apparently still controls the orientation of contemporary folding.", url = "https://doi.org/10.1139/e81-019", doi = "10.1139/e81-019", openalex = "W2136419158", references = "doi101029tc001i005p00389, doi101144gsjgs13950605, doi1013065d25c4a516c111d78645000102c1865d, doi1013065d25cc9b16c111d78645000102c1865d, doi102113gssgfbulls7xvii61015" } @article{doi101144gsjgs14050741, author = "Sibson, Richard H.", title = "Continental fault structure and the shallow earthquake source", year = "1983", journal = "Journal of the Geological Society", abstract = "Plate boundaries in continental crust are generally less sharply defined than in the oceans, with seismicity spread over broad areas. Interplate displacements appear to be largely accommodated by networks of major fault zones. A simple 2-level model for these important structures accounts for the depth distribution of most continental earthquakes, and for the observed range of faulting styles and associated rock deformation textures. The model consists of a seismogenic frictional slip regime overlying quasi-plastic mylonite belts wherein shearing is largely accommodated aseismically, due mainly to the changing response of quartz to deformation with increasing temperature. Shear resistance increases with depth to a peak value in the vicinity of the frictiona1/quasi-plastic transition and then decreases rapidly. The depth to which microseismic activity extends appears inversely related to regional heat flow and can be satisfactorily modelled as the frictional/quasi-plastic transition for different geotherms using laboratory determined flow laws for quartz-bearing rocks. Larger earthquake ruptures (M > 5.5) tend to nucleate near the base of the seismogenic regime in the region inferred to have the highest shear resistance and concentration of distortional strain energy. Consideration is also given to the depression of isotherms and seismic activity in regions of thrusting, and to the question of the downward continuation of major fault zones through the lithosphere. Decoupling of the upper crust on flat-lying shear zones may accompany higher-level dip-slip (and perhaps in some circumstances, strike-slip) faulting, being favoured by above average continental heat flow and a high quartz content in the middle or deep crust. The average level of deviatoric stress within the seismogenic regime remains an outstanding problem.", url = "https://doi.org/10.1144/gsjgs.140.5.0741", doi = "10.1144/gsjgs.140.5.0741", openalex = "W2011939763", references = "doi101007bf00876528, doi1010160022509659900298, doi101029jb082i020p02981, doi101029jb084ib05p02348, doi101029rg016i004p00621, doi101098rspa19570133, doi101098rsta19760079, doi101111j1365246x1972tb02351x, doi101126science1894201419, doi101144gsjgs13330191, doi101785bssa0650051073, openalexw2002729176" } @article{doi101111j1365246x1984tb01931x, author = "Jackson, James and McKenzie, Dan", title = "Active tectonics of the Alpine--Himalayan Belt between western Turkey and Pakistan", year = "1984", journal = "Geophysical Journal International", abstract = "Over 80 new fault plane solutions, combined with satellite imagery as well as both modern and historical observations of earthquake faulting, are used to investigate the active tectonics of the Middle East between western Turkey and Pakistan. The deformation of the western part of this region is dominated by the movement of continental material laterally away from the Lake Van region in eastern Turkey. This movement helps to avoid crustal thickening in the Van region, and allows some of the shortening between Arabia and Eurasia to be taken up by the thrusting of continental material over oceanic-type basement in the southern Caspian, Mediterranean, Makran and Black Sea. Thus central Turkey, bounded by the North and East Anatolian strike-slip faults, is moving west from the Van region and overrides the eastern Mediterranean at two intermediate depth seismic zones: one extending between Antalya Bay and southern Cyprus, and the other further west in the Hellenic Trench. The motion of northern Iran eastwards from the Van region is achieved mainly by a conjugate system of strike-slip faults and leads to the low angle thrusting of Iran over the southern Caspian Sea. The seismicity of the Caucasus shows predominantly shortening perpendicular to the regional strike, but there is also some minor elongation along the strike of the belt as the Causcasus overrides the Caspian and Black Seas. The deformation of the eastern part of this region is dominated by the shortening of Iran against the stable borders of Turkmenistan and Afghanistan. The north-east direction of compression seen in Zagros is also seen in north-east Iran and the Kopet Dag, where the shortening is taken up by a combination of strike-slip and thrust faulting. Large structural as well as palaeomagnetic rotations are likely to have occurred in NE Iran as a result of this style of deformation. North-south strike-slip faults in southern Iran allow some movement of material away from the collision zone in NE Iran towards the Makran subduction zone, where genuinely intermediate depth seismicity is seen. Within this broad deforming belt large areas, such as central Turkey, NW Iran (Azerbaijan), central Iran and the southern Caspian, appear to be almost aseismic and therefore to behave as relatively rigid blocks surrounded by active belts 200-300 km wide. The motion of these blocks can usefully be described by poles of rotation. The poles presented in this paper predict motions consistent with those observed and also predict the opening of the Gulf of Iskenderun NE of Cyprus, the change within the Zagros mountains from strike-slip faulting in the NW to intense thrusting in the SE, and the relatively feeble seismicity in SE Iran (Baluchistan). This description also explains why the north-south structures along the Iran-Afghanistan border do not cut the east-west ranges of the Makran. Within the active belts surrounding the relatively aseismic blocks a continuum approach is needed for a description of the deformation, even though motions at the surface may be concentrated on faults. The evolution of fault systems within the active zones is controlled by geometric constraints, such as the requirement that simultaneously active faults do not, in general, intersect. Many of the active processes discussed in this paper, particularly large-scale rotations and lateral movement along the regional strike, are likely to have caused substantial complexities in older mountain belts and should be accounted for in any reconstructions of them.", url = "https://doi.org/10.1111/j.1365-246x.1984.tb01931.x", doi = "10.1111/j.1365-246x.1984.tb01931.x", openalex = "W2133274607", references = "doi1010160012821x78900511, doi1010160012821x78900717, doi1010160040195178901403, doi101029jb088ib05p04183, doi101029rg016i004p00621, doi101139e81019, doi101144gsjgs13950605, doi1013062f918a8b16ce11d78645000102c1865d, openalexw1491817880" } @article{doi101144gsjgs14440531, author = "Floyd, P.A. and Leveridge, Brian E.", title = "Tectonic environment of the Devonian Gramscatho basin, south Cornwall: framework mode and geochemical evidence from turbiditic sandstones", year = "1987", journal = "Journal of the Geological Society", abstract = "The Portscatho Formation, within the allochthonous unit of the Middle and Upper Devonian Gramscatho Group, is a thick sequence of deep-water sandstones and interbedded slates deposited by southerly-derived turbidity currents into the Gramscatho basin of south Cornwall. Throughout an approximately 3.5 km thick sequence, the Portscatho Formation is petrographically and chemically coherent, except that the upper section shows a higher proportion of metamorphic clasts, high, but variable Cr, and low, uniform Zr abundances. Complementary framework mode and bulk geochemistry indicate that the sandstones were derived from a dissected continental magmatic arc of predominantly acidic composition, similar to average upper continental crust, but with an admixture of minor intermediate/basic material. Flysch deposition took place in a fore-arc setting. The presence of an arc to the south of Cornwall during the Devonian implies that there was subduction at the margin of the Gramscatho basin, whose ultimate closure was accommodated by the northward stacking of flysch–ophiolite nappes.", url = "https://doi.org/10.1144/gsjgs.144.4.0531", doi = "10.1144/gsjgs.144.4.0531", openalex = "W2124460270", references = "doi1010160016703769901264, doi1010160016703776900934, doi1010160031920186900932, doi1010160037073881900749, doi101086625710, doi101086628416, doi101086628815, doi1010970001069419520900000020, doi1010970001069419730500000019, doi101098rsta19810119, doi1013062f9182e316ce11d78645000102c1865d, doi1013062f9188fb16ce11d78645000102c1865d, doi101306c1ea4f7716c911d78645000102c1865d, openalexw1624806571, openalexw3120543430" } @article{doi101098rsta19880135, author = "Dewey, John and SHACKLETON, R. and Chengfa, Chang and Yiyin, Sun", title = "The tectonic evolution of the Tibetan Plateau", year = "1988", journal = "Philosophical Transactions of the Royal Society of London Series A Mathematical and Physical Sciences", abstract = "Abstract The Tibetan Plateau, between the Kunlun Shan and the Himalayas, consists of terranes accreted successively to Eurasia. The northernmost, the Songban Ganzi Terrane, was accreted to the Kunlun (Tarim-North China Terrane) along the Kunlun-Qinling Suture during the late Permian. The Qiangtang Terrane accreted to the Songban-Ganzi along the Jinsha Suture during the late Triassic or earliest Jurassic, the Lhasa Terrane to the Qiangtang along the Banggong Suture during the late Jurassic and, finally, Peninsular India to the Lhasa Terrane along the Zangbo Suture during the Middle Eocene. The Kunlun Shan, Qiangtang and Lhasa Terranes are all underlain by Precambrian continental crust at least a billion years old. The Qiangtang and Lhasa Terranes came from Gondwanaland. Substantial southward ophiolite obduction occurred across the Lhasa Terrane from the Banggong Suture in the late Jurassic and from the Zangbo Suture in the latest Cretaceous-earliest Palaeocene. Palaeomagnetic data suggest successive wide Palaeotethyan oceans during the late Palaeozoic and early Mesozoic and a Neotethys which was at least 6000 km wide during the mid-Cretaceous. Thickening of the Tibetan crust to almost double the normal thickness occurred by northward-migrating north-south shortening and vertical stretching during the mid-Eocene to earliest Miocene indentation of Asia by India; Neogene strata are almost flat-lying and rest unconformably upon Palaeogene or older strata. Since the early Miocene, the northward motion of India has been accommodated principally by north south shortening both north and south of Tibet. From early Pliocene to the Present, the Tibetan Plateau has risen by about two kilometres and has suffered east-west extension. Little, if any, of the India Eurasia convergence has been accommodated by eastward lateral extrusion.", url = "https://doi.org/10.1098/rsta.1988.0135", doi = "10.1098/rsta.1988.0135", openalex = "W2016760315", references = "crossref1974the, doi101029jb075i014p02625, doi101029jb083ib10p04975, doi101038211676a0, doi101038279590a0, doi101144transed83387, doi102475ajs27511" } @article{doi101086629470, author = "McLennan, S. M. and Taylor, S. R.", title = "Sedimentary Rocks and Crustal Evolution: Tectonic Setting and Secular Trends", year = "1991", journal = "The Journal of Geology", abstract = "A significant change in the composition of turbidites deposited at active tectonic settings is seen at the Archean/post-Archean transition. In comparison to post-Archean active margin turbidites, Archean greenstone turbidites exhibit more uniform Th/Sc ratios (but with a similar average), greater HREE-depletion ($$Gd\_{N}/Yb\_{N} >2$$), less Eu-depletion (Eu/Eu* mostly >0.85) and an absence of low Th/U ratios (Th/ U >3). These data indicate that differing mantle sources and/or conditions of mantle melting existed during the Archean and that intracrustally differentiated rocks (older cratons or young differentiated arcs) were relatively unimportant as provenance components for Archean turbidites. In contrast, some sedimentary rocks preserved in Archean platformal sequences of high-grade terranes display significant negative Eu-anomalies similar to the majority of post-Archean shales, indicating that the general process of cratonization, including intracrustal differentiation, has taken place since at least 3.8 Ga. However, several lines of evidence indicate that the overall extent of such regions was minor. On balance, the sedimentary data are consistent with a change in upper crustal composition at the end of the Archean, representing a first-order feature in the geological record. It is generally agreed that a major episode of continental growth also occurred at the end of the Archean and that crustal growth appears episodic throughout earth history. Crustal growth also appears to be early, with most models suggesting >50\% of the crust in place by about 2.5 Ga. Early crustal growth is consistent with a hotter Archean earth, but discontinuous aspects of crustal evolution are not so readily understood for a continually cooling earth. It may be possible to reconcile these features by considering the effects of supercontinental cycles, beginning in the late Archean, superimposed on a framework of secular earth cooling.", url = "https://doi.org/10.1086/629470", doi = "10.1086/629470", openalex = "W2011611022", references = "doi1010160016703776900934, doi1010160025322784902093, doi1010160301926886900173, doi101144gsjgs14440531, doi101146annurevea08050180002103" } @article{doi101111j1365246x1991tb06724x, author = "Kennett, B. L. N. and Engdahl, E. R.", title = "Traveltimes for global earthquake location and phase identification", year = "1991", journal = "Geophysical Journal International", abstract = "Over the last three years, a major international effort has been made by the Sub-Commission on Earthquake Algorithms of the International Association of Seismology and the Physics of the Earth's Interior (IASPEI) to generate new global traveltime tables for seismic phases to update the tables of Jeffreys \& Bullen (1940). The new tables are specifically designed for convenient computational use, with high-accuracy interpolation in both depth and range. The new iasp91 traveltime tables are derived from a radially stratified velocity model which has been constructed so that the times for the major seismic phases are consistent with the reported times for events in the catalogue of the International Seismological Centre (ISC) for the period 1964–1987. The baseline for the P-wave traveltimes in the iasp91 model has been adjusted to provide only a small bias in origin time for well-constrained events at the main nuclear testing sites around the world. For P-waves at teleseismic distances, the new tables are about 0.7s slower than the 1968 P-tables (Herrin 1968) and on average about 1.8-1.9 s faster than the Jeffreys \& Bullen (1940) tables. For S-waves the teleseismic times lie between those of the JB tables and the results of Randall (1971). Because the times for all phases are derived from the same velocity model, there is complete consistency between the traveltimes for different phases at different focal depths. The calculation scheme adopted for the new iasp91 tables is that proposed by Buland \& Chapman (1983). Tables of delay time as a function of slowness are stored for each traveltime branch, and interpolated using a specially designed tau spline which takes care of square-root singularities in the derivative of the traveltime curve at certain critical slownesses. With this representation, once the source depth is specified, it is straightforward to find the traveltime explicitly for a given epicentral distance. The computational cost is no higher than a conventional look-up table, but there is increased accuracy in constructing the traveltimes for a source at arbitrary depth. A further advantage over standard tables is that exactly the same procedure can be used for each phase. For a given source depth, it is therefore possible to generate very rapidly a comprehensive list of traveltimes and associated derivatives for the main seismic phases which could be observed at a given epicentral distance.", url = "https://doi.org/10.1111/j.1365-246x.1991.tb06724.x", doi = "10.1111/j.1365-246x.1991.tb06724.x", openalex = "W2103113534", references = "doi1010160031920181900467" } @article{doi101086648222, author = "McLennan, S. M.", title = "Weathering and Global Denudation", year = "1993", journal = "The Journal of Geology", abstract = "A negative correlation between sediment yield and weathering history, as measured by the chemical alteration (CIA) of the suspended sediment, is observed for many of the world's major rivers and other regions of denudation. The weathering history is a first-order control on the sediment yield of such areas, termed equilibrium denudation regions. For other areas, data scatter with either apparent increases or decreases of sediment yield for given CIA values. These areas are termed nonequilibrium denudation regions. Low sediment yields can be attributed to moderated erosion (either natural or human induced) and/or the incorporation of unweathered glacial debris. Accelerated erosion, resulting in high sediment yield, is primarily human-induced and results from cultivation and other land use. Each of these effects has a profound influence on global sediment discharge from the continents. Pre-human suspended sediment discharge from the continents is estimated to be $$12.6 \times 10^{15} g/yr$$ or about 0.6 the present discharge.", url = "https://doi.org/10.1086/648222", doi = "10.1086/648222", openalex = "W1966207504", references = "doi101086628741, doi101086628992, doi101086629606" } @article{doi101146annurevea22050194001535, author = "Stern, Robert J.", title = "ARC ASSEMBLY AND CONTINENTAL COLLISION IN THE NEOPROTEROZOIC EAST AFRICAN OROGEN: Implications for the Consolidation of Gondwanaland", year = "1994", journal = "Annual Review of Earth and Planetary Sciences", abstract = "Some of the most important, rapid, and enigmatic changes in our Earth’s environment and biota occurred during the Neoproterozoic Era (1000540 million years ago; Ma). Paramount among these changes are the rapid evolution of eukaryotes and appearance of metazoa (Knoll 1992, Conway Morris 1993), major episodes of continental glaciation that may have extended to low latitudes (Hambrey \& Harland 1985), marked increases in the oxygen concentration of the atmosphere and hydrosphere (Derry et al 1992), the reappearance of sedimentary banded iron formations (BIF; James 1983), and striking temporal variations in the isotopic composition of C and Sr (Asmerom et al 1991, Derry et al 1992). Understanding the causes of and relationships between these changes is a challenging focus of interdisciplinary research, and there are compelling indications that the most important causes were tectonic (Des Marais et al 1992, Veevers 1990). For example, development of ocean basins may have been accompanied by the development of seafloor hydrothermal systems, which lowered the 87Sr/S6Sr of seawater, led to the development of BIF, and formed anoxic basins where organic carbon could be buried, thus leading to an increase in O\textasciitilde . Continental collision and formation of a supercontinent may have led to continental glaciation and an increase in the 87Sr/86Sr of seawater,", url = "https://doi.org/10.1146/annurev.ea.22.050194.001535", doi = "10.1146/annurev.ea.22.050194.001535", openalex = "W2174216460" } @article{doi101126science27753341956, author = "Smith, Walter H. F. and Sandwell, David T.", title = "Global Sea Floor Topography from Satellite Altimetry and Ship Depth Soundings", year = "1997", journal = "Science", abstract = "A digital bathymetric map of the oceans with a horizontal resolution of 1 to 12 kilometers was derived by combining available depth soundings with high-resolution marine gravity information from the Geosat and ERS-1 spacecraft. Previous global bathymetric maps lacked features such as the 1600-kilometer-long Foundation Seamounts chain in the South Pacific. This map shows relations among the distributions of depth, sea floor area, and sea floor age that do not fit the predictions of deterministic models of subsidence due to lithosphere cooling but may be explained by a stochastic model in which randomly distributed reheating events warm the lithosphere and raise the ocean floor.", url = "https://doi.org/10.1126/science.277.5334.1956", doi = "10.1126/science.277.5334.1956", openalex = "W2021959819", references = "doi101017s0022112067001880, doi10102990eo00319, doi10102994jb00988, doi10102996jb01781, doi10102996jb03223, doi101029jb082i005p00803, doi101038359123a0, doi101126science27653201831, doi101130001676061978891389rbeass20co2, doi10119011442837" } @article{doi101785bssa0880030722, author = "Engdahl, E. R. and van der Hilst, Rob and Buland, Raymond P.", title = "Global teleseismic earthquake relocation with improved travel times and procedures for depth determination", year = "1998", journal = "Bulletin of the Seismological Society of America", abstract = "Abstract We relocate nearly 100,000 events that occurred during the period 1964 to 1995 and are well-constrained teleseismically by arrival-time data reported to the International Seismological Centre (ISC) and to the U.S. Geological Survey's National Earthquake Information Center (NEIC). Hypocenter determination is significantly improved by using, in addition to regional and teleseismic P and S phases, the arrival times of PKiKP, PKPdf, and the teleseismic depth phases pP, pwP, and sP in the relocation procedure. A global probability model developed for later-arriving phases is used to independently identify the depth phases. The relocations are compared to hypocenters reported in the ISC and NEIC catalogs and by other sources. Differences in our epicenters with respect to ISC and NEIC estimates are generally small and regionally systematic due to the combined effects of the observing station network and plate geometry regionally, differences in upper mantle travel times between the reference earth models used, and the use of later-arriving phases. Focal depths are improved substantially over most other independent estimates, demonstrating (for example) how regional structures such as downgoing slabs can severely bias depth estimation when only regional and teleseismic P arrivals are used to determine the hypocenter. The new data base, which is complete to about Mw 5.2 and includes all events for which moment-tensor solutions are available, has immediate application to high-resolution definition of Wadati-Benioff Zones (WBZs) worldwide, regional and global tomographic imaging, and other studies of earth structure.", url = "https://doi.org/10.1785/bssa0880030722", doi = "10.1785/bssa0880030722", openalex = "W1913469372", references = "doi101029jb086ib04p02825" } @article{doi101017s0263593300007367, author = "Jahn, Bor‐ming and Wu, Fu‐Yuan and Chen, Bin", title = "Granitoids of the Central Asian Orogenic Belt and continental growth in the Phanerozoic", year = "2000", journal = "Earth and Environmental Science Transactions of the Royal Society of Edinburgh", abstract = "The Central Asian Orogenic Belt (CAOB), also known as the Altaid Tectonic Collage, is characterised by a vast distribution of Paleozoic and Mesozoic granitic intrusions. The granitoids have a wide range of compositions and roughly show a temporal evolution from calcalkaline to alkaline to peralkaline series. The emplacement times for most granitic plutons fall between 500 Ma and 100 Ma, but only a small proportion of plutons have been precisely dated. The Nd-Sr isotopic compositions of these granitoids suggest their juvenile characteristics, hence implying a massive addition of new continental crust in the Phanerozoic. In this paper we document the available isotopic data to support this conclusion. Most Phanerozoic granitoids of Central Asia are characterised by low initial Sr isotopic ratios, positive ε Nd (T) values and young Sm—Nd model ages (T DM) of 300-1200 Ma. This is in strong contrast with the coeval granitoids emplaced in the European Caledonides and Hercynides. The isotope data indicate their ‘juvenile’ character and suggest their derivation from source rocks or magmas separated shortly before from the upper mantle. Granitoids with negative ε Nd (T) values also exist, but they occur in the environs of Precambrian microcontinental blocks and their isotope compositions may reflect contamination by the older crust in the magma generation processes. The evolution of the CAOB is probably related to accretion of young arc complexes and old terranes (microcontinents). However, the emplacement of large volumes of post-tectonic granites requires another mechanism, probably through a series of processes including underplating of massive basaltic magma, intercalation of basaltic magma with lower crustal granulites, partial melting of the mixed lithologic assemblages leading to generation of granitic liquids, followed by extensive fractional crystallisation. The proportions of the juvenile or mantle component for most granitoids of Central Asia are estimated to vary from 70\% to 100\%.", url = "https://doi.org/10.1017/s0263593300007367", doi = "10.1017/s0263593300007367", openalex = "W2103463307", references = "doi101016s0040195100001761, doi101029gd021, doi101038364299a0" } @article{doi1010291999jb900351, author = "McClusky, S. and Balassanian, S. and Barka, Aykut and Demir, Coșkun and Ergintav, Semih and Georgiev, Ivan and Gurkan, O. and Hamburger, Michael and Hurst, K. and Kahle, H.‐G. and Kastens, Kim A. and Kekelidze, G. and King, R. W. and Kotzev, V. and Lenk, Onur and Mahmoud, Salah and Mishin, A. V. and Nadariya, M. and Ouzounis, Ares and Paradissis, D. and Peter, Yannick and Prilepin, M. T. and Reilinger, R. E. and Sanli, I. and Seeger, H. and Tealeb, A. and Toksöz, M. Nafi and Veis, G.", title = "Global Positioning System constraints on plate kinematics and dynamics in the eastern Mediterranean and Caucasus", year = "2000", journal = "Journal of Geophysical Research Atmospheres", abstract = "We present and interpret Global Positioning System (GPS) measurements of crustal motions for the period 1988–1997 at 189 sites extending east‐west from the Caucasus mountains to the Adriatic Sea and north‐south from the southern edge of the Eurasian plate to the northern edge of the African plate. Sites on the northern Arabian platform move 18±2 mm/yr at N25°±5°W relative to Eurasia, less than the NUVEL‐1A circuit closure rate (25±1 mm/yr at N21°±7°W). Preliminary motion estimates (1994–1997) for stations located in Egypt on the northeastern part of Africa show northward motion at 5–6±2 mm/yr, also slower than NUVEL‐IA estimates (10±1 mm/yr at N2°±4°E). Eastern Turkey is characterized by distributed deformation, while central Turkey is characterized by coherent plate motion (internal deformation of <2 mm/yr) involving westward displacement and counterclockwise rotation of the Anatolian plate. The Anatolian plate is de‐coupled from Eurasia along the right‐lateral, strike‐slip North Anatolian fault (NAF). We derive a best fitting Euler vector for Anatolia‐Eurasia motion of 30.7°± 0.8°N, 32.6°± 0.4°E, 1.2°±0.1°/Myr. The Euler vector gives an upper bound for NAF slip rate of 24±1 mm/yr. We determine a preliminary GPS Arabia‐Anatolia Euler vector of 32.9°±1.2°N, 40.3°±1.1°E, 0.8°±0.2°/Myr and an upper bound on left‐lateral slip on the East Anatolian fault (EAF) of 9±1 mm/yr. The central and southern Aegean is characterized by coherent motion (internal deformation of <2 mm/yr) toward the SW at 30±1 mm/yr relative to Eurasia. Stations in the SE Aegean deviate significantly from the overall motion of the southern Aegean, showing increasing velocities toward the trench and reaching 10±1 mm/yr relative to the southern Aegean as a whole.", url = "https://doi.org/10.1029/1999jb900351", doi = "10.1029/1999jb900351", openalex = "W2023815011", references = "doi101002eqe4290170101, doi10102994gl02118, doi10102995eo00198, doi10102995jb00317, doi10102996jb03736, doi101029gd021, doi101029jb073i018p05855, doi101029jb086ib04p02825, doi101029tc007i003p00663, doi101038226239a0, doi101111j1365246x1972tb02351x, doi101111j1365246x1990tb06579x, doi101111j1365246x1996tb05264x, doi101126science1894201419, doi102110pec85370211, doi102110pec85370227, openalexw3041301201" } @article{doi1010292000gc000109, author = "McLennan, S. M.", title = "Relationships between the trace element composition of sedimentary rocks and upper continental crust", year = "2001", journal = "Geochemistry Geophysics Geosystems", abstract = "Estimates of the average composition of various Precambrian shields and a variety of estimates of the average composition of upper continental crust show considerable disagreement for a number of trace elements, including Ti, Nb, Ta, Cs, Cr, Ni, V, and Co. For these elements and others that are carried predominantly in terrigenous sediment, rather than in solution (and ultimately into chemical sediment), during the erosion of continents the La/element ratio is relatively uniform in clastic sediments. Since the average rare earth element (REE) pattern of terrigenous sediment is widely accepted to reflect the upper continental crust, such correlations provide robust estimates of upper crustal abundances for these trace elements directly from the sedimentary data. Suggested revisions to the upper crustal abundances of Taylor and McLennan [1985] are as follows (all in parts per million): Sc = 13.6, Ti = 4100, V = 107, Cr = 83, Co = 17, Ni = 44, Nb = 12, Cs = 4.6, Ta = 1.0, and Pb = 17. The upper crustal abundances of Rb, Zr, Ba, Hf, and Th were also directly reevaluated and K, U, and Rb indirectly evaluated (by assuming Th/U, K/U, and K/Rb ratios), and no revisions are warranted for these elements. In the models of crustal composition proposed by Taylor and McLennan [1985] the lower continental crust (75\% of the entire crust) is determined by subtraction of the upper crust (25\%) from a model composition for the bulk crust, and accordingly, these changes also necessitate revisions to lower crustal abundances for these elements.", url = "https://doi.org/10.1029/2000gc000109", doi = "10.1029/2000gc000109", openalex = "W1880555926", references = "doi101007bf00375292, doi1010160016703764901292, doi1010160016703776900934, doi101086628992, doi1015159781501509032010, openalexw2094255421" } @article{doi101046j13653121200100327x, author = "Matte, Ph.", title = "The Variscan collage and orogeny (480–290 Ma) and the tectonic definition of the Armorica microplate: a review", year = "2001", journal = "Terra Nova", abstract = "The Variscan belt of western Europe is part of a large Palaeozoic mountain system, 1000 km broad and 8000 km long, which extended from the Caucasus to the Appalachian and Ouachita mountains of northern America at the end of the Carboniferous. This system, built between 480 and 250 Ma, resulted from the diachronic collision of two continents: Laurentia–Baltica to the NW and Gondwana to the SE. Between these two continents, small, intermediate continental plates separated by oceanic sutures mainly have been defined (based on palaeomagnetism) as Avalonia and Armorica. They are generally assumed to have been detached from Gondwana during the early Ordovician and docked to Laurentia and Baltica before the Carboniferous collision between Gondwana and Laurentia–Baltica. Palaeomagnetic and palaeobiostratigraphic methods allow two main oceanic basins to be distinguished: the Iapetus ocean between Avalonia and Laurentia and between Laurentia and Baltica, with a lateral branch (Tornquist ocean) between Avalonia and Baltica, and the Rheic ocean between Avalonia and the so‐called Armorica microplate. Closure of the Iapetus ocean led to the Caledonian orogeny: a belt resulting from collision between Laurentia and Baltica, and from softer collisions between Avalonia and Laurentia and between Avalonia and Baltica. Closure of the Rheic ocean led to the Variscan orogeny by collision of Avalonia plus Armorica with Gondwana. A tectonic approach allows this scenario to be further refined. Another important oceanic suture is defined: the Galicia–Southern Brittany suture, running through France and Iberia and separating the Armorica microplate into North Armorica and South Armorica. Its closure by northward (or/and westward?) oceanic and then continental subduction led to early Variscan (430–370 Ma) tectonism and metamorphism in the internal parts of the Variscan belt. As no Palaeozoic suture can be detected south of South Armorica, this latter microplate should be considered as part of Gondwana since early Palaeozoic times and during its Palaeozoic north‐westward drift. Thus, the name Armorica should be restricted to the microplate included between the Rheic and the Galicia–Southern Brittany sutures.", url = "https://doi.org/10.1046/j.1365-3121.2001.00327.x", doi = "10.1046/j.1365-3121.2001.00327.x", openalex = "W1993859923", references = "doi101017cbo9780511524936, doi101130001676061977881305lpsfis20co2, doi101144gslmem19900120101" } @article{doi101144gslsp20042260105, author = "Jahn, Bor‐ming", title = "The Central Asian Orogenic Belt and growth of the continental crust in the Phanerozoic", year = "2004", journal = "Geological Society London Special Publications", abstract = "Abstract Asia is the world’s largest composite continent, comprising numerous old cratonic blocks and young mobile belts. During the Phanerozoic it was enlarged by successive accretion of dispersed Gondwana-derived terranes. The opening and closing of palaeo-oceans would have inevitably produced a certain amount of fresh mantle-derived juvenile crust. The Central Asian Orogenic Belt (CAOB), otherwise known as the Altaid tectonic collage, is now celebrated for its accretionary tectonics and massive juvenile crustal production in the Phanerozoic. It is composed of a variety of tectonic units, including Precambrian microcontinental blocks, ancient island arcs, ocean island, accretionary complexes, ophiolites and passive continental margins. Yet, the most outstanding feature is the vast expanse of granitic intrusions and their volcanic equivalents. Since granitoids are generated in lower-to-middle crustal conditions, they are used to probe the nature of their crustal sources, and to evaluate the relative contribution of juvenile v. recycled crust in the orogenic belts. Using the Nd-Sr isotope tracer technique, the majority of granitoids from the CAOB can be shown to contain high proportions (60 to 100\%) of the mantle component in their generation. This implies an important crustal growth in continental scale during the period of 500–100 Ma. The evolution of the CAOB undoubtedly involved both lateral and vertical accretion of juvenile material. The lateral accretion implies stacking of arc complexes, accompanied by amalgamation of old microcontinental blocks. Parts of the accreted arc assemblages were later converted into granitoids via underplating of basaltic magmas. The emplacement of large volumes of post-accretionary alkaline and peralkaline granites was most likely achieved by vertical accretion through a series of processes, including underplating of basaltic magma, mixing of basaltic liquid with lower-crustal rocks, partial melting of the mixed lithologies leading to generation of granitic liquids, and followed by fractional crystallization. The recognition of vast juvenile terranes in the Canadian Cordillera, the western US, the Appalachians and the Central Asian Orogenic Belt has considerably changed our view on the growth rate of the continental crust in the Phanerozoic.", url = "https://doi.org/10.1144/gsl.sp.2004.226.01.05", doi = "10.1144/gsl.sp.2004.226.01.05", openalex = "W2169016685", references = "doi101016004019519090004r, doi101016s0040195100001761, doi101016s1367912003001305, doi1018814epiiugs2000v23i2001" } @article{doi101146annurevearth32082503144359, author = "Peltier, W. R.", title = "GLOBAL GLACIAL ISOSTASY AND THE SURFACE OF THE ICE-AGE EARTH: The ICE-5G (VM2) Model and GRACE", year = "2004", journal = "Annual Review of Earth and Planetary Sciences", abstract = "▪ Abstract The 100 kyr quasiperiodic variation of continental ice cover, which has been a persistent feature of climate system evolution throughout the most recent 900 kyr of Earth history, has occurred as a consequence of changes in the seasonal insolation regime forced by the influence of gravitational n-body effects in the Solar System on the geometry of Earth's orbit around the Sun. The impacts of the changing surface ice load upon both Earth's shape and gravitational field, as well as upon sea-level history, have come to be measurable using a variety of geological and geophysical techniques. These observations are invertible to obtain useful information on both the internal viscoelastic structure of the solid Earth and on the detailed spatiotemporal characteristics of glaciation history. This review focuses upon the most recent advances that have been achieved in each of these areas, advances that have proven to be central to the construction of the refined model of the global process of glacial isostatic adjustment, denoted ICE-5G (VM2). A significant test of this new global model will be provided by the global measurement of the time dependence of the gravity field of the planet that will be delivered by the GRACE satellite system that is now in space.", url = "https://doi.org/10.1146/annurev.earth.32.082503.144359", doi = "10.1146/annurev.earth.32.082503.144359", openalex = "W2112363056", references = "doi1010160031920181900467, doi1010160033589478900339, doi101017s0033822200019123, doi10102990jb01583, doi101029jb073i022p07089, doi101029rg010i003p00761, doi101029rg012i004p00649, doi101029rg020i002p00219, doi101038342637a0, doi101038345405a0, doi10103835021035, doi101038364218a0, doi101046j1365246x199800541x, doi101111j1365246x1976tb01251x, doi101111j1365246x1976tb01253x, doi101111j1365246x1982tb04976x, doi101126science1072497, doi101126science2605109771, doi101126science2655169195, doi101126science28754612225, doi101126science28954861897, doi101144gsjgs15230437" } @article{doi102475ajs3044370, author = "Xiao, Wenjiao", title = "Paleozoic accretionary and collisional tectonics of the eastern Tianshan (China): Implications for the continental growth of central Asia", year = "2004", journal = "American Journal of Science", abstract = "This paper deals with the various tectonic units in the Chinese Eastern Tianshan orogenic collage in the Central Asian Orogenic Belt, and discusses the Paleozoic geological history of the several periods of accretion and collision of archipelago systems lying between the Tarim and southern Angaran continental margins. The Late Ordovician-Silurian to Early Devonian Eastern Tianshan archipelago was characterized by (a) the Harlik-Dananhu subduction system with a S-dipping polarity in the north; (b) a southerly N-dipping subduction system beneath the Central Tianshan arc in the middle; and (c) the South Tianshan ocean against Tarim in the south. During the Devonian to Early Carboniferous, N-dipping subduction led to the Harlik-Dananhu arc and the Kanggurtag forearc basin/accretionary complex. In the Early to Mid-Carboniferous, the magmatic front associated with the N-dipping subduction beneath the Dananhu-Harlik arc migrated southwards, forming the Yamansu arc constructed upon the Kanggurtag accretionary forearc. By the Late Carboniferous the Dananhu-Harlik arc was attached northwards to the Angaran margin, resulting in lateral enlargement of the Angaran continent. In the latest Carboniferous to Early Permian a multiple soft collision left wide suture zones in the south that include the ophiolite-strewn Aqikkuduk-Shaquanzi and Kumishi accretion-collision complexes, which were stitched by Early Permian post-collisional plutons. By re-defining and re-interpreting the various tectonic terranes, this paper presents a new, improved model for the Paleozoic evolution of this part of Central Asia.", url = "https://doi.org/10.2475/ajs.304.4.370", doi = "10.2475/ajs.304.4.370", openalex = "W2162457106", references = "doi101016004019519090004r, doi1010160040195193902259, doi101016s0040195100001761, doi1010292002tc001484, doi1011440016764903165" } @article{doi101126science1116412, author = "Miller, Kenneth G. and Kominz, Michelle A. and Browning, James V. and Wright, James D. and Mountain, Gregory S. and Katz, Miriam and Sugarman, Peter J. and Cramer, Benjamin S. and Christie‐Blick, Nicholas and Pekar, Stephen F.", title = "The Phanerozoic Record of Global Sea-Level Change", year = "2005", journal = "Science", abstract = "We review Phanerozoic sea-level changes [543 million years ago (Ma) to the present] on various time scales and present a new sea-level record for the past 100 million years (My). Long-term sea level peaked at 100 +/- 50 meters during the Cretaceous, implying that ocean-crust production rates were much lower than previously inferred. Sea level mirrors oxygen isotope variations, reflecting ice-volume change on the 10(4)- to 10(6)-year scale, but a link between oxygen isotope and sea level on the 10(7)-year scale must be due to temperature changes that we attribute to tectonically controlled carbon dioxide variations. Sea-level change has influenced phytoplankton evolution, ocean chemistry, and the loci of carbonate, organic carbon, and siliciclastic sediment burial. Over the past 100 My, sea-level changes reflect global climate evolution from a time of ephemeral Antarctic ice sheets (100 to 33 Ma), through a time of large ice sheets primarily in Antarctica (33 to 2.5 Ma), to a world with large Antarctic and large, variable Northern Hemisphere ice sheets (2.5 Ma to the present).", url = "https://doi.org/10.1126/science.1116412", doi = "10.1126/science.1116412", openalex = "W2153985161", references = "doi1010160012821x96000623, doi101017cbo9780511628948, doi10102990jb02015, doi10102992jb01202, doi10102994jb01889, doi10102998rg01624, doi101029pa002i001p00001, doi101038297391a0, doi101038339532a0, doi1010510004636120041335, doi101126science1059412, doi101126science19442701121, doi101126science23547931156, doi1011300016760619637493sitcio20co2, doi1023073515270, doi102475ajs294156, doi102475ajs3012182, donovan1979causes" } @article{doi1010292005jb004051, author = "Reilinger, Robert and McClusky, S. and Vernant, Philippe and Lawrence, Shawn and Ergintav, Semih and Çakmak, R. and Özener, Haluk and Kadirov, Fakhraddin and Guliev, I. S. and Stepanyan, Ruben and Nadariya, M. and Hahubia, Galaktion and Mahmoud, Salah and Sakr, Kamal and ArRajehi, Abdullah and Paradissis, Demitris and Al‐Aydrus, A. and Prilepin, Mikhail Tikhonovich and Гусева, Т.В. and Evren, Emre and Dmitrotsa, A. I. and Filikov, S. V. and Gomez, Francisco and Al-Ghazzi, R. and Karam, Gebran N.", title = "GPS constraints on continental deformation in the Africa‐Arabia‐Eurasia continental collision zone and implications for the dynamics of plate interactions", year = "2006", journal = "Journal of Geophysical Research Atmospheres", abstract = "The GPS‐derived velocity field (1988–2005) for the zone of interaction of the Arabian, African (Nubian, Somalian), and Eurasian plates indicates counterclockwise rotation of a broad area of the Earth's surface including the Arabian plate, adjacent parts of the Zagros and central Iran, Turkey, and the Aegean/Peloponnesus relative to Eurasia at rates in the range of 20–30 mm/yr. This relatively rapid motion occurs within the framework of the slow‐moving (∼5 mm/yr relative motions) Eurasian, Nubian, and Somalian plates. The circulatory pattern of motion increases in rate toward the Hellenic trench system. We develop an elastic block model to constrain present‐day plate motions (relative Euler vectors), regional deformation within the interplate zone, and slip rates for major faults. Substantial areas of continental lithosphere within the region of plate interaction show coherent motion with internal deformations below ∼1–2 mm/yr, including central and eastern Anatolia (Turkey), the southwestern Aegean/Peloponnesus, the Lesser Caucasus, and Central Iran. Geodetic slip rates for major block‐bounding structures are mostly comparable to geologic rates estimated for the most recent geological period (∼3–5 Myr). We find that the convergence of Arabia with Eurasia is accommodated in large part by lateral transport within the interior part of the collision zone and lithospheric shortening along the Caucasus and Zagros mountain belts around the periphery of the collision zone. In addition, we find that the principal boundary between the westerly moving Anatolian plate and Arabia (East Anatolian fault) is presently characterized by pure left‐lateral strike slip with no fault‐normal convergence. This implies that “extrusion” is not presently inducing westward motion of Anatolia. On the basis of the observed kinematics, we hypothesize that deformation in the Africa‐Arabia‐Eurasia collision zone is driven in large part by rollback of the subducting African lithosphere beneath the Hellenic and Cyprus trenches aided by slab pull on the southeastern side of the subducting Arabian plate along the Makran subduction zone. We further suggest that the separation of Arabia from Africa is a response to plate motions induced by active subduction.", url = "https://doi.org/10.1029/2005jb004051", doi = "10.1029/2005jb004051", openalex = "W1981165981", references = "doi1010160040195181902754, doi1010291999jb900351, doi1010292000jb000033, doi1010292002jb001862, doi10102994gl02118, doi10102995eo00198, doi10102995jb00317, doi10102996jb03736, doi101029jb073i018p05855, doi101038226239a0, doi101111j1365246x1972tb02351x, doi101111j1365246x1990tb06579x, doi101111j1365246x1996tb05264x, doi101126science105978, doi101126science1894201419, doi101126science29054981910, doi10113000917613198210611petian20co2, doi101146annurevearth32101802120415, doi101146annurevearth33092203122711, doi101785bssa0750041135, doi102110pec85370211, doi102110pec85370227, openalexw304861154" } @article{doi101126science1129158, author = "Sepulchre, Pierre and Ramstein, Gilles and Fluteau, Frédéric and Schuster, Mathieu and Tiercelin, Jean‐Jacques and Brunet, Michel", title = "Tectonic Uplift and Eastern Africa Aridification", year = "2006", journal = "Science", abstract = "The history of Eastern African hominids has been linked to a progressive increase of open grassland during the past 8 million years. This trend was explained by global climatic processes, which do not account for the massive uplift of eastern African topography that occurred during this period. Atmosphere and biosphere simulations quantify the role played by these tectonic events. The reduced topographic barrier before 8 million years ago permitted a zonal circulation with associated moisture transport and strong precipitation. Our results suggest that the uplift itself led to a drastic reorganization of atmospheric circulation, engendering the strong aridification and paleoenvironmental changes suggested by the data.", url = "https://doi.org/10.1126/science.1129158", doi = "10.1126/science.1129158", openalex = "W2063333127", references = "doi101016jjafrearsci200507019" } @article{doi101144001676492006022, author = "Windley, Brian F. and Alexeiev, D. V. and Xiao, Wenjiao and Kröner, Alfred and Badarch, Gombosuren", title = "Tectonic models for accretion of the Central Asian Orogenic Belt", year = "2006", journal = "Journal of the Geological Society", abstract = "The Central Asian Orogenic Belt (c. 1000–250 Ma) formed by accretion of island arcs, ophiolites, oceanic islands, seamounts, accretionary wedges, oceanic plateaux and microcontinents in a manner comparable with that of circum-Pacific Mesozoic–Cenozoic accretionary orogens. Palaeomagnetic and palaeofloral data indicate that early accretion (Vendian–Ordovician) took place when Baltica and Siberia were separated by a wide ocean. Island arcs and Precambrian microcontinents accreted to the active margins of the two continents or amalgamated in an oceanic setting (as in Kazakhstan) by roll-back and collision, forming a huge accretionary collage. The Palaeo-Asian Ocean closed in the Permian with formation of the Solonker suture. We evaluate contrasting tectonic models for the evolution of the orogenic belt. Current information provides little support for the main tenets of the one- or three-arc Kipchak model; current data suggest that an archipelago-type (Indonesian) model is more viable. Some diagnostic features of ridge–trench interaction are present in the Central Asian orogen (e.g. granites, adakites, boninites, near-trench magmatism, Alaskan-type mafic–ultramafic complexes, high-temperature metamorphic belts that prograde rapidly from low-grade belts, rhyolitic ash-fall tuffs). They offer a promising perspective for future investigations.", url = "https://doi.org/10.1144/0016-76492006-022", doi = "10.1144/0016-76492006-022", openalex = "W2003323528", references = "doi101016jearscirev200504001, doi101016s0012825200000210, doi101016s0040195100001761, doi101016s0169136801000166, doi101016s0301926802002188, doi101016s1367912002000172, doi101016s1367912003001305, doi101017s0263593300007367, doi1010292002tc001484, doi101029gd021, doi101038364299a0, doi1011300091761319900180128paacro23co2, doi1011440016764903165, doi101144gslsp20042260105, doi102475ajs3044370, openalexw2346629672" } @article{doi1018814epiiugs2006v29i1004, author = "Zhou, Xinmin and Sun, Tao and Shen, Weizhou and Shu, Liangshu and Niu, Yaoling", title = "Petrogenesis of Mesozoic granitoids and volcanic rocks in South China: A response to tectonic evolution", year = "2006", journal = "Episodes", abstract = "This paper summarizes the new results on the petrogenesis of Mesozoic granitoids and volcanic rocks in South China. The authors propose that these rocks were formed in time and space as a response to regional tectonic regime change from the continent-continent collision of the Indosinian orogeny within the broad Tethyan orogenic domain in the Early Mesozoic (T 1 -T 3) (Period I) to the largely extensional setting as a result of the Yanshanian orogeny genetically associated with the NW-WNW-ward subduction of the paleo-Pacific oceanic lithosphere in the Late Mesozoic (J 2 -K 2) (Period II). Of the Period I Indosinian granitoids, the early (T 1 -T 2 1) ones are syn-collisional, and formed in a compressional setting; the late (T 2 2 -T 3) ones are latecollisional, and formed in a locally extensional environment. During the Period II Yanshanian magmatism, the Early Yanshanian (J 2 -J 3) granitoid-volcanic rocks, which are distributed mainly in the Nanling Range and in the interior of the South China tectonic block (SCB), are characteristic of rift-type intraplate magmatism, whereas the Late Yanshanian K 1 granitoid-volcanic rocks are interpreted as genetically representing active continental margin magmatism. The K 2 tholeiitic basalts interlayered with red beds are interpreted as genetically associated with the development of back-arc extensional basins in the interior of the SCB. The Yanshanian granitoid-volcanic rocks are distributed widely in South China, reflecting extensional tectonics within much of the SCB. The extension-induced deep crustal melting and underplating of mantle-derived basaltic melts are suggested as the two principal driving mechanisms for the Yanshanian granitic magmatism in South China.", url = "https://doi.org/10.18814/epiiugs/2006/v29i1/004", doi = "10.18814/epiiugs/2006/v29i1/004", openalex = "W1525258218" } @article{doi101073pnas0608378104, author = "Roelants, Kim and Gower, David J. and Wilkinson, Mark and Loader, Simon P. and Biju, S. D. and Guillaume, Karen and Moriau, Linde and Bossuyt, Franky", title = "Global patterns of diversification in the history of modern amphibians", year = "2007", journal = "Proceedings of the National Academy of Sciences", abstract = "The fossil record of modern amphibians (frogs, salamanders, and caecilians) provides no evidence for major extinction or radiation episodes throughout most of the Mesozoic and early Tertiary. However, long-term gradual diversification is difficult to reconcile with the sensitivity of present-day amphibian faunas to rapid ecological changes and the incidence of similar environmental perturbations in the past that have been associated with high turnover rates in other land vertebrates. To provide a comprehensive overview of the history of amphibian diversification, we constructed a phylogenetic timetree based on a multigene data set of 3.75 kb for 171 species. Our analyses reveal several episodes of accelerated amphibian diversification, which do not fit models of gradual lineage accumulation. Global turning points in the phylogenetic and ecological diversification occurred after the end-Permian mass extinction and in the late Cretaceous. Fluctuations in amphibian diversification show strong temporal correlation with turnover rates in amniotes and the rise of angiosperm-dominated forests. Approximately 86\% of modern frog species and >81\% of salamander species descended from only five ancestral lineages that produced major radiations in the late Cretaceous and early Tertiary. This proportionally late accumulation of extant lineage diversity contrasts with the long evolutionary history of amphibians but is in line with the Tertiary increase in fossil abundance toward the present.", url = "https://doi.org/10.1073/pnas.0608378104", doi = "10.1073/pnas.0608378104", openalex = "W2114910448", references = "doi101023a1011317930838, doi101073pnas0401892101, doi1012060003009020062970001tatol20co2, doi104095215638, doi10560219780801847806, doi105860choice331556" } @article{doi101371journalpbio0050157, author = "Jetz, Walter and Wilcove, David S. and Dobson, Andrew P.", title = "Projected Impacts of Climate and Land-Use Change on the Global Diversity of Birds", year = "2007", journal = "PLoS Biology", abstract = "Over the past few decades, land-use and climate change have led to substantial range contractions and species extinctions. Even more dramatic changes to global land cover are projected for this century. We used the Millennium Ecosystem Assessment scenarios to evaluate the exposure of all 8,750 land bird species to projected land-cover changes due to climate and land-use change. For this first baseline assessment, we assumed stationary geographic ranges that may overestimate actual losses in geographic range. Even under environmentally benign scenarios, at least 400 species are projected to suffer >50\% range reductions by the year 2050 (over 900 by the year 2100). Although expected climate change effects at high latitudes are significant, species most at risk are predominantly narrow-ranged and endemic to the tropics, where projected range contractions are driven by anthropogenic land conversions. Most of these species are currently not recognized as imperiled. The causes, magnitude and geographic patterns of potential range loss vary across socioeconomic scenarios, but all scenarios (even the most environmentally benign ones) result in large declines of many species. Whereas climate change will severely affect biodiversity, in the near future, land-use change in tropical countries may lead to yet greater species loss. A vastly expanded reserve network in the tropics, coupled with more ambitious goals to reduce climate change, will be needed to minimize global extinctions.", url = "https://doi.org/10.1371/journal.pbio.0050157", doi = "10.1371/journal.pbio.0050157", openalex = "W2116159613", references = "doi101073pnas0401892101" } @article{doi1010292008jb005860, author = "D’Agostino, N. and Avallone, A. and Cheloni, Daniele and D’Anastasio, E. and Mantenuto, S. and Selvaggi, G.", title = "Active tectonics of the Adriatic region from GPS and earthquake slip vectors", year = "2008", journal = "Journal of Geophysical Research Atmospheres", abstract = "To investigate the kinematics of the Adriatic region, we integrate continuous and episodic GPS measurements with M w > 4.5 earthquake slip vectors selected from the Regional Centroid Moment Tensor catalogue. Coherent motion of GPS sites in the Po Valley, in Apulia, and in the Hyblean Plateau allows us to estimate geodetically constrained angular velocities for these regions. The predictions of the GPS‐inferred angular velocities are compared with the earthquake slip vectors, showing that the seismically expressed deformation at the microplate boundaries is consistent with the observed geodetic motion. The remarkable consistency between geodetic, seismological, and geological evidence of active tectonics suggests that active deformation in the central Adriatic is controlled by the relative motion between the Adria and Apulia microplates. The microplates' angular rotation rates are then compared with the rotation rates calculated with a simple block model supporting the hypotheses (1) that Apulia forms a single microplate with the Ionian Sea and possibly with the Hyblean region and (2) that Adria and Apulia rotate in such a way as to accommodate the Eurasia‐Nubia relative motion. We suggest that the present‐day microplate configuration follows a recent fragmentation of the Adriatic promontory that during the Neogene rigidly transferred the Africa motion to the orogenic belts that now surround the Adriatic region.", url = "https://doi.org/10.1029/2008jb005860", doi = "10.1029/2008jb005860", openalex = "W1978055661", references = "doi1010292005jb004051" } @article{doi1010292008jb005821, author = "Goertz-Allmann, Bettina and Shearer, Peter M.", title = "Global variations of stress drop for moderate to large earthquakes", year = "2009", journal = "Journal of Geophysical Research Atmospheres", abstract = "We investigate the global variation of earthquake stress drops using spectra of about 2000 events of m b ≥ 5.5 between 1990 and 2007. We use an iterative least squares method to isolate source displacement spectra from travel path and receiver contributions, based on a convolutional model. The observed P wave source spectra are corrected with a globally averaged empirical correction spectrum and estimates of near‐source attenuation. Assuming a Brune‐type source model, we estimate corner frequencies and compute stress drops. Stress drop estimates for individual earthquakes range from about 0.3 to 50 MPa, but the median stress drop of about 4 MPa does not vary with moment, implying earthquake self‐similarity over the M w = 5.2 to 8.3 range of our data. A comparison of our results with previous studies confirms this observation over most of the instrumentally observable magnitude range. While the absolute values of our estimated stress drops depend upon the assumed source model, we identify relative regional variations of stress drop that are robust with respect to the processing parameters and modeling assumptions, which includes an inherent assumption of constant rupture velocity. We find a dependence of median stress drop on focal mechanism, with a factor of 3–5 times higher stress drops for strike‐slip earthquakes and also find a factor of 2 times higher stress drops for intraplate earthquakes compared to interplate earthquakes.", url = "https://doi.org/10.1029/2008jb005821", doi = "10.1029/2008jb005821", openalex = "W2077076159", references = "doi10102997jb02122, doi101029jb086ib04p02825, doi101046j1365246x200201720x" } @article{doi101093petrologyegp082, author = "Liu, Yongsheng and Gao, Shunbao and Hu, Zhaoping and Gao, Chengjin and Zong, Keqing and Wang, Dongyan", title = "Continental and Oceanic Crust Recycling-induced Melt-Peridotite Interactions in the Trans-North China Orogen: U-Pb Dating, Hf Isotopes and Trace Elements in Zircons from Mantle Xenoliths", year = "2009", journal = "Journal of Petrology", abstract = "We present the first finding of continental crust-derived Precambrian zircons in garnet/spinel pyroxenite veins within mantle xenoliths carried by the Neogene Hannuoba basalt in the central zone of the North China Craton (NCC). Petrological and geochemical features indicate that these mantle-derived composite xenoliths were formed by silicic melt^lherzolite interaction. The Precambrian zircon ages can be classified into three age groups of 2·4^2·5 Ga, 1·6^2·2 Ga and 0·6^1·2 Ga, coinciding with major geological events in the NCC. These Precambrian zircons fall in the field of continental granitoid rocks in plots of U/Yb vs Hf and Y. Their igneous-type REE patterns and metamorphic zircon type CL images indicate that they were not crystallized during melt^peridotite interaction and subsequent high-pressure metamorphism.The 2·5 Ga zircons have positive eHf(t) values (2·9^10·6), whereas the younger Precambrian zircons are dominated by negative eHf(t) values, indicating an ancient continental crustal origin.These observations suggest that the Precambrian zircons were xenocrysts that survived melting of recycled continental crustal rocks and were then injected with silicate melt into the host peridotite. In addition to the Precambrian zircons, igneous zircons of 315 3 Ma (2), 80^170 Ma and 48^64 Ma were separated from the garnet/spinel pyroxenite veins; these provide evidence for lower continental crust and oceanic crust recycling-induced multi-episodic melt^peridotite interactions in the central zone of the NCC. The combination of the positive eHf(t) values (2·91^24·6) of the 315 Ma zircons with the rare occurrence of 302^324 Ma subduction-related diorite^granite plutons in the northern margin of the NCC implies that the 315 Ma igneous zircons might record melt^peridotite interactions in the lithospheric mantle induced by Palaeo-Asian oceanic crust subduction. Igneous zircons of age 80^170 Ma generally coexist with the Precambrian metamorphic zircons and have lower Ce/Yb and Th/U ratios, higher U/Yb ratios and greater negative Eu anomalies.The eHf(t) values of these zircons vary greatly from ^47·6 to 24·6.The 170^110 Ma zircons are generally characterized by negative eHf(t) values, whereas the 110^100 Ma zircons have positive eHf(t) values.These observations suggest that melt^peridotite interactions at 80^170 Ma were induced by partial melting of recycled continental crust. The 48^64 Ma igneous zircons are characterized by negligible Ce anomalies, unusually high REE, U and Th contents, and positive eHf(t) values.These features imply that the melt^peridotite interactions at 48^64 Ma could be associated with a depleted mantle-derived carbonate melt or fluid.", url = "https://doi.org/10.1093/petrology/egp082", doi = "10.1093/petrology/egp082", openalex = "W2140093647", references = "doi101016b9780080959757003016, doi101016jchemgeo200406017, doi101016jchemgeo200808004, doi101016s0009254100002333, doi101016s0009254101003552, doi101016s000925410200195x, doi1010292002tc001484, doi101039ja9961100899, doi101111j1751908x1995tb00147x, doi101126science1061372, doi101126science1140516, doi101144001676492006022, doi1021130530469, openalexw1624806571, openalexw2797914455" } @article{doi1010292009jb007205, author = "Kent, Dennis V. and Irving, E.", title = "Influence of inclination error in sedimentary rocks on the Triassic and Jurassic apparent pole wander path for North America and implications for Cordilleran tectonics", year = "2010", journal = "Journal of Geophysical Research Atmospheres", abstract = "Because of paleomagnetic inclination error (I error) in sedimentary rocks, we argue that previous estimates of Triassic and Jurassic paleolatitudes of the North American craton have generally been too low, the record being derived mostly from sedimentary rocks. Using results from all major cratons, we construct a new composite apparent pole wander (APW) path for Triassic through Paleogene based on 69 paleopoles ranging in age from 243 to 43 Ma. The poles are from igneous rocks and certain sedimentary formations corrected for I error brought into North American coordinates using plate tectonic reconstructions. Key features of the new APW path are a 25° northward progression from 230 to 190 Ma to high latitudes (off northernmost Siberia) where the pole lingers until 160 Ma, a jump to the Aleutians followed by a hook in western Alaska by ∼145 Ma that leads to the 130–60 Ma stillstand, after which the pole moves to its present position. As an example of the application of this new path we use paleomagnetic results to determine that southern Wrangellia and Stikinia (W/S), the two most westerly terranes in the Canadian Cordillera, lay 630 to 1650 km farther south than at present relative to the craton during the Late Triassic and Early Jurassic. This is consistent with an exotic Tethyan origin as paleontological and mantle geochemical evidences imply. During the Late Triassic through Early Cretaceous, W/S moved northward more slowly than the craton, implying oblique sinistral net convergence over this 130 Myr interval. This was followed by dextral shear in latest Cretaceous through Eocene.", url = "https://doi.org/10.1029/2009jb007205", doi = "10.1029/2009jb007205", openalex = "W2160012670", references = "doi1010160012821x75902216, doi101029jb091ib11p11519, doi101111j1365246x1964tb06300x, doi101126science28253972241" } @article{doi101144001676492009072, author = "Hawkesworth, Chris J. and Dhuime, Bruno and Pietranik, Anna and Cawood, Peter A. and Kemp, Anthony I.S. and Storey, Craig", title = "The generation and evolution of the continental crust", year = "2010", journal = "Journal of the Geological Society", abstract = "Abstract: The continental crust is the archive of the geological history of the Earth. Only 7\% of the crust is older than 2.5 Ga, and yet significantly more crust was generated before 2.5 Ga than subsequently. Zircons offer robust records of the magmatic and crust-forming events preserved in the continental crust. They yield marked peaks of ages of crystallization and of crust formation. The latter might reflect periods of high rates of crust generation, and as such be due to magmatism associated with deep-seated mantle plumes. Alternatively the peaks are artefacts of preservation, they mark the times of supercontinent formation, and magmas generated in some tectonic settings may be preferentially preserved. There is increasing evidence that depletion of the upper mantle was in response to early planetary differentiation events. Arguments in favour of large volumes of continental crust before the end of the Archaean, and the thickness of felsic and mafic crust, therefore rely on thermal models for the progressively cooling Earth. They are consistent with recent estimates that the rates of crust generation and destruction along modern subduction zones are strikingly similar. The implication is that the present volume of continental crust was established 2–3 Ga ago.", url = "https://doi.org/10.1144/0016-76492009-072", doi = "10.1144/0016-76492009-072", openalex = "W2163100615", references = "doi1010160016703787903619, doi101144sp3181, openalexw1487925322" } @article{doi101130b304461, author = "Dilek, Yıldırım and Furnes, Harald", title = "Ophiolite genesis and global tectonics: Geochemical and tectonic fingerprinting of ancient oceanic lithosphere", year = "2011", journal = "Geological Society of America Bulletin", url = "https://doi.org/10.1130/b30446.1", doi = "10.1130/b30446.1", openalex = "W1969845853", references = "doi1010160012821x82901200, doi1010160016703778902223, doi101016jgr200908001, doi101016jgr201001007, doi101029jb076i014p03179, doi101111j14401738200500478x, doi101130gsatg24a1, doi101130petrologic1962599, doi1011440016764903165, doi101144sp3181" } @article{doi101016jearscirev201203002, author = "Seton, Maria and Müller, R. Dietmar and Zahirovic, Sabin and Gaina, Carmen and Torsvik, Trond H. and Shephard, Grace E. and Talsma, A. S. and Gurnis, Michael and Turner, M. and Maus, S. and Chandler, Michael T.", title = "Global continental and ocean basin reconstructions since 200Ma", year = "2012", journal = "Earth-Science Reviews", url = "https://doi.org/10.1016/j.earscirev.2012.03.002", doi = "10.1016/j.earscirev.2012.03.002", openalex = "W2137335718", references = "crossref1974the, doi101016003101829190145h, doi101016004019518590006x, doi101016jearscirev200702001, doi101016jearscirev200908001, doi101016jpalaeo200606041, doi101016s0012821x00002314, doi101016s0012821x0100588x, doi101016s0012821x99001314, doi101016s1367912001000694, doi101016s1367912002000172, doi101017cbo9780511536045, doi1010292001gc000252, doi1010292005jb004035, doi1010292006tc001970, doi1010292007gc001743, doi10102992jb01202, doi10102994jb01889, doi10102994jb03098, doi10102996jb03223, doi101029jb073i006p02119, doi101029jb084ib03p01071, doi101029jb084ib12p06803, doi101038224125a0, doi101038225139a0, doi101038nature04800, doi10108008120099608728282, doi101111j1365246x1990tb06579x, doi101111j1365246x200904137x, doi101111j1365246x200904491x, doi101126science2675199852, doi101130001676061973841105ctaiaa20co2, doi10113000167606197788969eotns20co2, doi1011300016760619981100801psonrm23co2, doi1011300813723604333, doi101130dnaggnam351, doi101130mem132p7, doi101130spe206, doi101144sp2822, doi102475ajs3042105, doi102973odpprocsr1271281992, openalexw2989049194, openalexw641398428" } @article{doi101130b307221, author = "Cawood, Peter A. and Hawkesworth, C. J. and Dhuime, Bruno", title = "The continental record and the generation of continental crust", year = "2012", journal = "Geological Society of America Bulletin", abstract = "Continental crust is the archive of Earth history. The spatial and temporal distribution of Earth's record of rock units and events is heterogeneous; for example, ages of igneous crystallization, metamorphism, continental margins, mineralization, and seawater and atmospheric proxies are distributed about a series of peaks and troughs. This distribution reflects the different preservation potential of rocks generated in different tectonic settings, rather than fundamental pulses of activity, and the peaks of ages are linked to the timing of supercontinent assembly. The physio-chemical resilience of zircons and their derivation largely from felsic igneous rocks means that they are important indicators of the crustal record. Furthermore, detrital zircons, which sample a range of source rocks, provide a more representative record than direct analysis of grains in igneous rocks. Analysis of detrital zircons suggests that at least ∼60\%–70\% of the present volume of the continental crust had been generated by 3 Ga. Such estimates seek to take account of the extent to which the old crustal material is underrepresented in the sedimentary record, and they imply that there were greater volumes of continental crust in the Archean than might be inferred from the compositions of detrital zircons and sediments. The growth of continental crust was a continuous rather than an episodic process, but there was a marked decrease in the rate of crustal growth at ca. 3 Ga, which may have been linked to the onset of significant crustal recycling, probably through subduction at convergent plate margins. The Hadean and Early Archean continental record is poorly preserved and characterized by a bimodal TTG (tonalites, trondhjemites, and granodiorites) and greenstone association that differs from the younger record that can be more directly related to a plate-tectonic regime. The paucity of this early record has led to competing and equivocal models invoking plate-tectonic– and mantle-plume–dominated processes. The 60\%–70\% of the present volume of the continental crust estimated to have been present at 3 Ga contrasts markedly with the <10\% of crust of that age apparently still preserved and requires ongoing destruction (recycling) of crust and subcontinental mantle lithosphere back into the mantle through processes such as subduction and delamination.", url = "https://doi.org/10.1130/b30722.1", doi = "10.1130/b30722.1", openalex = "W2136857107", references = "doi101016jgca200511008, doi101016jlithos200307003, doi101016s0301926801001607, doi101017s0094837300004929, doi1010292003gc000597, doi10102997jb02122, doi101029gm100, doi101080037362451938105591187, doi1010970001069419540800000019, doi101126science17740541065, doi101130g329451" } @article{doi101002tect20013, author = "Ding, Lin and Yang, Di and Cai, Fulong and Pullen, Alex and Kapp, Paul and Gehrels, George E. and Zhang, Liyun and Zhang, Qinghai and Lai, Qingzhou and Yue, Yahui and Shi, R.", title = "Provenance analysis of the Mesozoic Hoh‐Xil‐Songpan‐Ganzi turbidites in northern Tibet: Implications for the tectonic evolution of the eastern Paleo‐Tethys Ocean", year = "2013", journal = "Tectonics", abstract = "Mesozoic strata of the Hoh‐Xil‐Songpan‐Ganzi complex in northern Tibet are exposed in a vast (> 370,000 km 2) triangle‐shaped orogenic belt bound by the Longmen Shan thrust belt in the east, the Kunlun terrane and North China block in the north, and the Qiangtang terrane and Yidun arc in the south. These strata consist of Middle–Upper Triassic submarine fan and deep marine facies rocks that were deposited in the Paleo‐Tethys Ocean. Late Triassic–Early Jurassic contractional deformation in the eastern Hoh‐Xil‐Songpan‐Ganzi complex marks the demise of the Paleo‐Tethys Ocean basin and the accretion of the Gondwana‐derived Qiangtang terrane to Eurasia. We conducted geological mapping, regional stratigraphic analyses, and U‐Pb geochronology of detrital zircons (n = 4128) on the Mesozoic sequences exposed in the Hoh‐Xil‐Songpan‐Ganzi complex, Kunlun terrane, and Qiangtang terrane. We identify for the first time marine silciclastic sandstone and shale of Jurassic age in the northwestern Hoh‐Xil‐Songpan‐Ganzi complex that unconformably overlie Upper Triassic turbidites. Zircon age data indicate that the Middle–Upper Triassic marine gravity‐flow deposits of the Hoh‐Xil‐Songpan‐Ganzi complex were shed from the North and South China blocks, and Middle–Late Triassic ultrahigh‐pressure Qinling–Dabie orogenic belt, as well as the Kunlun and Qiangtang terranes. In addition, the detrital zircon results suggest vast sediment source to sink distances (>1500 km) for the Middle–Upper Triassic Hoh‐Xil‐Songpan‐Ganzi strata, which is consistent with tectonic models for the Paleo‐Tethys Ocean basin that incorporate significant components of horizontal tectonic transport like opening of large back‐arc basins in response to oceanic slab rollback.", url = "https://doi.org/10.1002/tect.20013", doi = "10.1002/tect.20013", openalex = "W2116926271", references = "doi1010160012821x75900886, doi101016jprecamres200706005, doi101016s0012821x0100588x, doi1010292011tc002868, doi10102993tc00313, doi10102997eo00356, doi101098rsta19880135, doi101130spe195p1, doi101146annurevearth281211, openalexw2797914455" } @article{doi1010022014gc005407, author = "Kreemer, Corné and Blewitt, Geoffrey and Klein, Elliot C.", title = "A geodetic plate motion and Global Strain Rate Model", year = "2014", journal = "Geochemistry Geophysics Geosystems", abstract = "Abstract We present a new global model of plate motions and strain rates in plate boundary zones constrained by horizontal geodetic velocities. This Global Strain Rate Model (GSRM v.2.1) is a vast improvement over its predecessor both in terms of amount of data input as in an increase in spatial model resolution by factor of ∼2.5 in areas with dense data coverage. We determined 6739 velocities from time series of (mostly) continuous GPS measurements; i.e., by far the largest global velocity solution to date. We transformed 15,772 velocities from 233 (mostly) published studies onto our core solution to obtain 22,511 velocities in the same reference frame. Care is taken to not use velocities from stations (or time periods) that are affected by transient phenomena; i.e., this data set consists of velocities best representing the interseismic plate velocity. About 14\% of the Earth is allowed to deform in 145,086 deforming grid cells (0.25° longitude by 0.2° latitude in dimension). The remainder of the Earth's surface is modeled as rigid spherical caps representing 50 tectonic plates. For 36 plates we present new GPS‐derived angular velocities. For all the plates that can be compared with the most recent geologic plate motion model, we find that the difference in angular velocity is significant. The rigid‐body rotations are used as boundary conditions in the strain rate calculations. The strain rate field is modeled using the Haines and Holt method, which uses splines to obtain an self‐consistent interpolated velocity gradient tensor field, from which strain rates, vorticity rates, and expected velocities are derived. We also present expected faulting orientations in areas with significant vorticity, and update the no‐net rotation reference frame associated with our global velocity gradient field. Finally, we present a global map of recurrence times for M w =7.5 characteristic earthquakes.", url = "https://doi.org/10.1002/2014gc005407", doi = "10.1002/2014gc005407", openalex = "W2097951601", references = "doi101007s0019000600303, doi1010291999jb900351, doi1010292000jb000033, doi1010292001gc000252, doi1010292003jb002944, doi1010292005gl025546, doi1010292005jb004051, doi1010292011jb008930, doi10102991gl01532, doi10102992jb01963, doi101038226239a0, doi101046j1365246x200301917x, doi101111j1365246x200904491x, nugroho2009plate" } @article{doi101016jcub201403011, author = "Jetz, Walter and Thomas, Gavin H. and Joy, Jeffrey B. and Redding, David W. and Hartmann, Klaas and Mooers, Arne Ø.", title = "Global Distribution and Conservation of Evolutionary Distinctness in Birds", year = "2014", journal = "Current Biology", abstract = {BACKGROUND: Integrated, efficient, and global prioritization approaches are necessary to manage the ongoing loss of species and their associated function. "Evolutionary distinctness" measures a species' contribution to the total evolutionary history of its clade and is expected to capture uniquely divergent genomes and functions. Here we demonstrate how such a metric identifies species and regions of particular value for safeguarding evolutionary diversity. RESULTS: Among the world's 9,993 recognized bird species, evolutionary distinctness is very heterogeneously distributed on the phylogenetic tree and varies little with range size or threat level. Species representing the most evolutionary history over the smallest area (those with greatest "evolutionary distinctness rarity") as well as some of the most imperiled distinct species are often concentrated outside the species-rich regions and countries, suggesting they may not be well captured by current conservation planning. We perform global cross-species and spatial analyses and generate minimum conservation sets to assess the benefits of the presented species-level metrics. We find that prioritizing imperiled species by their evolutionary distinctness and geographic rarity is a surprisingly effective and spatially economical way to maintain the total evolutionary information encompassing the world's birds. We identify potential conservation gaps in relation to the existing reserve network that in particular highlight islands as effective priority areas. CONCLUSIONS: The presented distinctness metrics are effective yet easily communicable and versatile tools to assist objective global conservation decision making. Given that most species will remain ecologically understudied, combining growing phylogenetic and spatial data may be an efficient way to retain vital aspects of biodiversity.}, url = "https://doi.org/10.1016/j.cub.2014.03.011", doi = "10.1016/j.cub.2014.03.011", openalex = "W1979765668", references = "doi101073pnas0401892101, doi101093molbevmsl150, doi101126science2785338692" } @article{doi101016jgsf201401002, author = "Domeier, Mathew and Torsvik, Trond H.", title = "Plate tectonics in the late Paleozoic", year = "2014", journal = "Geoscience Frontiers", abstract = "As the chronicle of plate motions through time, paleogeography is fundamental to our understanding of plate tectonics and its role in shaping the geology of the present-day. To properly appreciate the history of tectonics—and its influence on the deep Earth and climate—it is imperative to seek an accurate and global model of paleogeography. However, owing to the incessant loss of oceanic lithosphere through subduction, the paleogeographic reconstruction of ‘full-plates’ (including oceanic lithosphere) becomes increasingly challenging with age. Prior to 150 Ma ∼60\% of the lithosphere is missing and reconstructions are developed without explicit regard for oceanic lithosphere or plate tectonic principles; in effect, reflecting the earlier mobilistic paradigm of continental drift. Although these ‘continental’ reconstructions have been immensely useful, the next-generation of mantle models requires global plate kinematic descriptions with full-plate reconstructions. Moreover, in disregarding (or only loosely applying) plate tectonic rules, continental reconstructions fail to take advantage of a wealth of additional information in the form of practical constraints. Following a series of new developments, both in geodynamic theory and analytical tools, it is now feasible to construct full-plate models that lend themselves to testing by the wider Earth-science community. Such a model is presented here for the late Paleozoic (410–250 Ma) together with a review of the underlying data. Although we expect this model to be particularly useful for numerical mantle modeling, we hope that it will also serve as a general framework for understanding late Paleozoic tectonics, one on which future improvements can be built and further tested.", url = "https://doi.org/10.1016/j.gsf.2014.01.002", doi = "10.1016/j.gsf.2014.01.002", openalex = "W2028904790", references = "doi101016jearscirev201203002, doi101016jearscirev201206007, doi101016jgr201202019, doi101016jjseaes201103002, doi101016s0012821x0100588x, doi1010292001gc000252, doi1010292002tc001484, doi101111j1365246x200904491x, doi101139e81019, doi101144001676492006022, doi101144gslsp20052460112" } @article{doi101126science1258213, author = "Sandwell, David T. and Müller, R. Dietmar and Smith, Walter H. F. and Garcia, E. S. M. and Francis, R.", title = "New global marine gravity model from CryoSat-2 and Jason-1 reveals buried tectonic structure", year = "2014", journal = "Science", abstract = "Gravity models are powerful tools for mapping tectonic structures, especially in the deep ocean basins where the topography remains unmapped by ships or is buried by thick sediment. We combined new radar altimeter measurements from satellites CryoSat-2 and Jason-1 with existing data to construct a global marine gravity model that is two times more accurate than previous models. We found an extinct spreading ridge in the Gulf of Mexico, a major propagating rift in the South Atlantic Ocean, abyssal hill fabric on slow-spreading ridges, and thousands of previously uncharted seamounts. These discoveries allow us to understand regional tectonic processes and highlight the importance of satellite-derived gravity models as one of the primary tools for the investigation of remote ocean basins.", url = "https://doi.org/10.1126/science.1258213", doi = "10.1126/science.1258213", openalex = "W2047018904", references = "doi1010160012821x78900365, doi101016jasr200507027, doi101016jearscirev201203002, doi1010292008jb006008, doi1010292011jb008916, doi101038207343a0, doi10110936718861, doi101126science27753341956, doi101144sp3281, doi105194se42152013" } @article{doi101130g363621, author = "Hou, Zengqian and Yang, Zhiming and Lu, Yongjun and Kemp, Anthony I.S. and Zheng, Yuanchuan and Li, Qiuyun and Tang, Juxing and Yang, Zhusen and Duan, Lianfeng", title = "A genetic linkage between subduction- and collision-related porphyry Cu deposits in continental collision zones", year = "2015", journal = "Geology", abstract = "The genesis of continental collision-related porphyry Cu deposits (PCDs) remains controversial. The most common hypothesis links their genesis with magmas derived from subduction-modified arc lithosphere. However, it is unclear whether a genetic linkage exists between collision- and subduction-related PCDs. Here, we studied Jurassic subduction-related Cu-Au and Miocene collision-related Cu-Mo porphyry deposits in south Tibet. The Jurassic PCDs occur only in the western segment of the Jurassic arc, which has depleted mantle-like isotopic compositions [e.g., (87Sr/86Sr)i = 0.7041–0.7048; εNd(t) as high as 7.5, and εHf(t) as high as 18]. By contrast, no Jurassic PCDs have been found in the eastern arc segment, which is isotopically less juvenile [e.g., (87Sr/86Sr)i = 0.7041–0.7063, εNd(t) < 4.5, and εHf(t) ≤ 12]. These results imply that incorporation of crustal components during underplating of Jurassic magma induced copper accumulation as sulfides at the base of the eastern Jurassic arc, inhibiting PCD formation at this time. Miocene PCDs are spatially confined to the Jurassic arc, and the giant Miocene PCDs cluster in its eastern segment where no Jurassic PCDs occur. This suggests that the arc segment barren for subduction-related PCDs could be fertile for collision-related PCDs. Miocene ore-forming porphyries have young Hf model ages and Sr-Nd-Hf isotopic compositions overlapping with those of the Jurassic rocks in the eastern segment, whereas contemporaneous barren porphyries outside the Jurassic arc have abundant zircon inheritance and crust-like Sr-Nd-Hf isotopic compositions. These data suggest that remelting of the lower crustal sulfide-bearing Cu-rich Jurassic cumulates, triggered by Cenozoic crustal thickening and/or subsequent slab break-off, led to the formation of giant Miocene PCDs. The spatial overlap and complementary metal endowment between subduction- and collision-related magmas may be used to evaluate the mineral potential for such deposits in other orogenic belts.", url = "https://doi.org/10.1130/g36362.1", doi = "10.1130/g36362.1", openalex = "W2110609253", references = "doi101016jjseaes201103002" } @article{doi1010022016jb012923, author = "Wu, Jonny and Suppe, John and Lu, Renqi and Kanda, R. V.", title = "Philippine Sea and East Asian plate tectonics since 52 Ma constrained by new subducted slab reconstruction methods", year = "2016", journal = "Journal of Geophysical Research Solid Earth", abstract = "Abstract We reconstructed Philippine Sea and East Asian plate tectonics since 52 Ma from 28 slabs mapped in 3‐D from global tomography, with a subducted area of \textasciitilde 25\% of present‐day global oceanic lithosphere. Slab constraints include subducted parts of existing Pacific, Indian, and Philippine Sea oceans, plus wholly subducted proto‐South China Sea and newly discovered “East Asian Sea.” Mapped slabs were unfolded and restored to the Earth surface using three methodologies and input to globally consistent plate reconstructions. Important constraints include the following: (1) the Ryukyu slab is \textasciitilde 1000 km N‐S, too short to account for \textasciitilde 20° Philippine Sea northward motion from paleolatitudes; (2) the Marianas‐Pacific subduction zone was at its present location (±200 km) since 48 ± 10 Ma based on a >1000 km deep slab wall; (3) the 8000 × 2500 km East Asian Sea existed between the Pacific and Indian Oceans at 52 Ma based on lower mantle flat slabs; (4) the Caroline back‐arc basin moved with the Pacific, based on the overlapping, coeval Caroline hot spot track. These new constraints allow two classes of Philippine Sea plate models, which we compared to paleomagnetic and geologic data. Our preferred model involves Philippine Sea nucleation above the Manus plume (0°/150°E) near the Pacific‐East Asian Sea plate boundary. Large Philippine Sea westward motion and post‐40 Ma maximum 80° clockwise rotation accompanied late Eocene‐Oligocene collision with the Caroline/Pacific plate. The Philippine Sea moved northward post‐25 Ma over the northern East Asian Sea, forming a northern Philippine Sea arc that collided with the SW Japan‐Ryukyu margin in the Miocene (\textasciitilde 20–14 Ma).", url = "https://doi.org/10.1002/2016jb012923", doi = "10.1002/2016jb012923", openalex = "W2374058458", references = "doi1010022013rg000444, doi101111j1365246x200904491x" } @article{doi101016jearscirev201609002, author = "Kusky, Timothy and Polat, Ali and Windley, Brian F. and Burke, Kevin and Dewey, John and Kidd, W. S. F. and Maruyama, S. and Wang, Junpeng and Deng, Hao and Wang, Zhuosheng and Wang, Cong and Fu, Dong and Li, Xiuti and Peng, Hongtao", title = "Insights into the tectonic evolution of the North China Craton through comparative tectonic analysis: A record of outward growth of Precambrian continents", year = "2016", journal = "Earth-Science Reviews", abstract = "Archean cratons have map patterns and rock associations that are diagnostic of the Wilson Cycle. The North China Craton (NCC) consists of several distinctly different tectonic units, but the delineation and understanding of the significance of individual sutures and the rocks between them has been controversial. We present an actualistic tectonic division and evolution of the North China Craton based on Wilson Cycle and comparative tectonic analysis that uses a multi-disciplinary approach in order to define sutures, their ages, and the nature of the rocks between them, to determine their mode of formation and means of accretion or exhumation, and propose appropriate modern analogues. The eastern unit of the craton consists of several different small blocks assembled between 2.6 and 2.7 Ga ago, that resemble fragments of accreted arcs from an assembled archipelago similar to those in the extant SW Pacific. A thick Atlantic-type passive margin developed on the western side of the newly assembled Eastern Block by 2.6–2.5 Ga. A > 1300 km-long arc and accretionary prism collided with the margin of the Eastern Block at 2.5 Ga, obducting ophiolites and ophiolitic mélanges onto the block, and depositing a thick clastic wedge in a foreland basin farther into the Eastern Block. This was followed by an arc-polarity reversal, which led to a short-lived injection of mantle wedge-derived melts to the base of the crust that led to the intrusion of mafic dikes and arc-type granitoid (TTG) plutons with associated metamorphism. By 2.43 Ga, the remaining open ocean west of the accreted arc closed with the collision of an oceanic plateau now preserved as the Western Block with the collision-modified margin of the Eastern Block, causing further deformation in the Central Orogenic Belt. 2.4–2.35 Ga rifting of the newly amalgamated continental block formed a rift along its center, and new oceans within the other two rift arms, which removed a still-unknown continental fragment from its northern margin. By 2.3 Ga an arc collided with a new Atlantic-type margin developed over the rift sequence along the northern margin of the craton, and thus was converted to an Andean margin through arc-polarity reversal. Andean margin tectonics affected much of the continental block from 2.3 to 1.9 Ga, giving rise to a broad E-W swath of continental margin magmas, and retro-arc sedimentary basins including a foreland basin superimposed on the passive northern margin. The horizontal extent of these tectonic components is similar to that across the present-day Andes in South America. From 1.88 to 1.79 Ga a granulite facies metamorphic event was superimposed across the entire continental block with high-pressure granulites and eclogites in the north, and medium-pressure granulites across the whole craton to the south. The scale and duration of this post-collisional event is similar to that in Central Asia that resulted from the Cenozoic India-Asia collision. The deep crustal granulites and volcanic rocks on the surface today, interpreted to be anatectic melts from deep crustal granulites, are similar to high-grade metamorphic rocks and partial melts presently forming at mid-crustal levels beneath Tibet. Structural fabrics in lower-crustal migmatites related to this event reveal that they flowed laterally parallel to the collision boundary, in a way comparable to what is speculated to be happening in the deep crust of the Himalayan/Tibetan foreland. We relate this continent-continent collision to the collision of the North China Craton with the postulated Columbia (Nuna) Continent. The NCC broke out of the Columbia Continent between 1753–1673 Ma, as shown by the formation of a suite of anorthosite, mangerite, charnockite, and alkali-feldspar granites in an ENE-striking belt along the northern margin of the craton, whose intrusion was followed by the development of rifts and graben, mafic dike swarms, and eventually an Atlantic-type passive margin that signaled the beginning of a long period of tectonic quiescence and carbonate deposition for the NCC during Sinian times, which persisted into the Paleozoic. The style of tectonic accretion in the NCC changed at circa 2.5 Ga, from an earlier phase of accretion of arcs that are presently preserved in horizontal lengths of several hundred kilometers, to the accretion and preservation of linear arcs several thousand kilometers long with associated oceanic plateaus, microcontinents, and accretionary prisms. The style of progressively younger and westward outward accretion of different tectonic components is reminiscent of the style of accretion in the Superior Craton, and may signal the formation of progressively larger landmasses at the end of the Archean (perhaps like the Kenorland Continent), then into the Paleoproterozoic, culminating in the assembly of the Columbia (Nuna) Continent at 1.9–1.8 Ga.", url = "https://doi.org/10.1016/j.earscirev.2016.09.002", doi = "10.1016/j.earscirev.2016.09.002", openalex = "W2507354539", references = "doi101146annurevearth060614105254" } @article{doi101038ncomms11461, author = "Leprieur, Fabien and Descombes, Patrice and Gaboriau, Théo and Cowman, Peter F. and Parravicini, Valériano and Kulbicki, Michel and Melián, Carlos J. and de Santana, Charles Novaes and Heine, Christian and Mouillot, David and Bellwood, David R. and Pellissier, Loïc", title = "Plate tectonics drive tropical reef biodiversity dynamics", year = "2016", journal = "Nature Communications", abstract = "The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics.", url = "https://doi.org/10.1038/ncomms11461", doi = "10.1038/ncomms11461", openalex = "W2345764476", references = "doi101371journalpone0126946" } @article{doi101146annurevearth060115012211, author = "Müller, R. Dietmar and Seton, Maria and Zahirovic, Sabin and Williams, Simon and Matthews, Kara J. and Wright, Nicky M. and Shephard, Grace E. and Maloney, Kayla and Barnett‐Moore, Nicholas and Hosseinpour, Maral and Bower, Dan J. and Cannon, John", title = "Ocean Basin Evolution and Global-Scale Plate Reorganization Events Since Pangea Breakup", year = "2016", journal = "Annual Review of Earth and Planetary Sciences", abstract = "We present a revised global plate motion model with continuously closing plate boundaries ranging from the Triassic at 230 Ma to the present day, assess differences among alternative absolute plate motion models, and review global tectonic events. Relatively high mean absolute plate motion rates of approximately 9–10 cm yr −1 between 140 and 120 Ma may be related to transient plate motion accelerations driven by the successive emplacement of a sequence of large igneous provinces during that time. An event at ∼100 Ma is most clearly expressed in the Indian Ocean and may reflect the initiation of Andean-style subduction along southern continental Eurasia, whereas an acceleration at ∼80 Ma of mean rates from 6 to 8 cm yr −1 reflects the initial northward acceleration of India and simultaneous speedups of plates in the Pacific. An event at ∼50 Ma expressed in relative, and some absolute, plate motion changes around the globe and in a reduction of global mean plate speeds from about 6 to 4–5 cm yr −1 indicates that an increase in collisional forces (such as the India–Eurasia collision) and ridge subduction events in the Pacific (such as the Izanagi–Pacific Ridge) play a significant role in modulating plate velocities.", url = "https://doi.org/10.1146/annurev-earth-060115-012211", doi = "10.1146/annurev-earth-060115-012211", openalex = "W2178317302", references = "doi101016jearscirev201203002, doi101016jearscirev201206007, doi101016jgloplacha201610002, doi1010292001gc000252, doi1010292007rg000227, doi10102994jb03098, doi10102996jb01781, doi101126science1151540, doi101126science1258213, openalexw2883478268" } @article{doi102138am20186166, author = "Brown, Michael and Johnson, Tim", title = "Secular change in metamorphism and the onset of global plate tectonics", year = "2017", journal = "American Mineralogist", abstract = "© 2018 Walter de Gruyter GmbH, Berlin/Boston 2018. On the contemporary Earth, distinct plate tectonic settings are characterized by differences in heat flow that are recorded in metamorphic rocks as differences in apparent thermal gradients. In this study we compile thermal gradients [defined as temperature/pressure (T/P) at the metamorphic peak] and ages of metamorphism (defined as the timing of the metamorphic peak) for 456 localities from the Eoarchean to Cenozoic Eras to test the null hypothesis that thermal gradients of metamorphism through time did not vary outside of the range expected for each of these distinct plate tectonic settings. Based on thermal gradients, metamorphic rocks are classified into three natural groups: high dT/dP [> 775 °C/GPa, mean \textasciitilde 1110 °C/GPa (n = 199) rates], intermediate dT/dP [775-375 °C/GPa, mean \textasciitilde 575 °C/GPa (n = 127)], and low dT/dP [< 375 °C/GPa, mean \textasciitilde 255 °C/GPa (n = 130)] metamorphism. Plots of T, P, and T/P against age demonstrate the widespread occurrence of two contrasting types of metamorphism -high dT/dP and intermediate dT/dP -in the rock record by the Neoarchean, the widespread occurrence of low dT/dP metamorphism in the rock record by the end of the Neoproterozoic, and a maximum in the thermal gradie nts for high dT/dP metamorphism during the period 2.3 to 0.85 Ga. These observations falsify the null hypothesis and support the alternative hypothesis that changes in thermal gradients evident in the metamorphic rock record were related to changes in geodynamic regime. Based on the observed secular changes, we postulate that the Earth has evolved through three geodynamic cycles since the Mesoarchean and has just entered a fourth. Cycle I began with the widespread appearance of paired metamorphism in the rock record, which was coeval with the amalgamation of widely dispersed blocks of protocontinental lithosphere into supercratons, and was terminated by the progressive fragmentation of the supercratons into protocontinents during the Siderian-Rhyacian (2.5 to 2.05 Ga). Cycle II commenced with the progressive reamalgamation of these protocontinents into the supercontinent Columbia and extended until the breakup of the supercontinent Rodinia in the Tonian (1.0 to 0.72 Ga). Thermal gradients of high dT/dP metamorphism rose around 2.3 Ga leading to a thermal maximum in the mid-Mesoproterozoic, reflecting insulation of the mantle beneath the quasi-integral continental lithosphere of Columbia, prior to the geographical reorganization of Columbia into Rodinia. This cycle coincides with the age span of most anorogenic magmatism on Earth and a scarcity of passive margins in the geological record. Intriguingly, the volume of preserved continental crust of Mesoproterozoic age is low relative to the Paleoproterozoic and Neoproterozoic Eras. These features are consistent with a relatively stable association of continental lithosphere between the assembly of Columbia and the breakup of Rodinia. The transition to Cycle III during the Tonian is marked by a steep decline in the thermal gradients of high dT/dP metamorphism to their lowest value and the appearance of low dT/dP metamorphism in the rock record. Again, thermal gradients for high dT/dP metamorphism show a rise to a peak at the end of the Variscides during the formation of Pangea, before another steep decline associated with the breakup of Pangea and the start of a fourth cycle at ca. 0.175 Ga. Although the mechanism by which subduction started and plate boundaries evolved remains uncertain, based on the widespread record of paired metamorphism in the Neoarchean we posit that plate tectonics was established globally during the late Mesoarchean. During the Neoproterozoic there was a change to deep subduction and colder thermal gradients, features characteristic of the modern plate tectonic regime.", url = "https://doi.org/10.2138/am-2018-6166", doi = "10.2138/am-2018-6166", openalex = "W2793317135", references = "doi101016jgr201704001, doi101017cbo9780511807442, doi101111j1365246x201004882x, doi101130g354021" } @article{doi101016jgsf201805011, author = "Young, Alexander and Flament, Nicolas and Maloney, Kayla and Williams, Simon and Matthews, Kara J. and Zahirovic, Sabin and Müller, R. Dietmar", title = "Global kinematics of tectonic plates and subduction zones since the late Paleozoic Era", year = "2018", journal = "Geoscience Frontiers", abstract = "Detailed global plate motion models that provide a continuous description of plate boundaries through time are an effective tool for exploring processes both at and below the Earth's surface. A new generation of numerical models of mantle dynamics pre- and post-Pangea timeframes requires global kinematic descriptions with full plate reconstructions extending into the Paleozoic (410 Ma). Current plate models that cover Paleozoic times are characterised by large plate speeds and trench migration rates because they assume that lowermost mantle structures are rigid and fixed through time. When used as a surface boundary constraint in geodynamic models, these plate reconstructions do not accurately reproduce the present-day structure of the lowermost mantle. Building upon previous work, we present a global plate motion model with continuously closing plate boundaries ranging from the early Devonian at 410 Ma to present day.We analyse the model in terms of surface kinematics and predicted lower mantle structure. The magnitude of global plate speeds has been greatly reduced in our reconstruction by modifying the evolution of the synthetic Panthalassa oceanic plates, implementing a Paleozoic reference frame independent of any geodynamic assumptions, and implementing revised models for the Paleozoic evolution of North and South China and the closure of the Rheic Ocean. Paleozoic (410–250 Ma) RMS plate speeds are on average ∼8 cm/yr, which is comparable to Mesozoic–Cenozoic rates of ∼6 cm/yr on average. Paleozoic global median values of trench migration trend from higher speeds (∼2.5 cm/yr) in the late Devonian to rates closer to 0 cm/yr at the end of the Permian (∼250 Ma), and during the Mesozoic–Cenozoic (250–0 Ma) generally cluster tightly around ∼1.1 cm/yr. Plate motions are best constrained over the past 130 Myr and calculations of global trench convergence rates over this period indicate median rates range between 3.2 cm/yr and 12.4 cm/yr with a present day median rate estimated at ∼5 cm/yr. For Paleozoic times (410–251 Ma) our model results in median convergence rates largely ∼5 cm/yr. Globally, ∼90\% of subduction zones modelled in our reconstruction are determined to be in a convergent regime for the period of 120–0 Ma. Over the full span of the model, from 410 Ma to 0 Ma, ∼93\% of subduction zones are calculated to be convergent, and at least 85\% of subduction zones are converging for 97\% of modelled times. Our changes improve global plate and trench kinematics since the late Paleozoic and our reconstructions of the lowermost mantle structure challenge the proposed fixity of lower mantle structures, suggesting that the eastern margin of the African LLSVP margin has moved by as much as ∼1450 km since late Permian times (260 Ma). The model of the plate-mantle system we present suggests that during the Permian Period, South China was proximal to the eastern margin of the African LLSVP and not the western margin of the Pacific LLSVP as previous thought. Keywords: Tectonic reconstruction, Paleozoic, Plate velocities, Subduction zone kinematics, Lower mantle structure, South China", url = "https://doi.org/10.1016/j.gsf.2018.05.011", doi = "10.1016/j.gsf.2018.05.011", openalex = "W2810727617", references = "doi101016jgr201303001, doi101016jgr201704001, doi101016s0012825201000794, doi1011302007242306, doi101130g25614a1, doi101144gslsp20052460112" } @article{doi101098rsta20170405, author = "Cawood, Peter A. and Hawkesworth, Chris J. and Pisarevsky, Sergei and Dhuime, Bruno and Capitanio, Fabio A. and Nebel, Oliver", title = "Geological archive of the onset of plate tectonics", year = "2018", journal = "Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering Sciences", abstract = "Plate tectonics, involving a globally linked system of lateral motion of rigid surface plates, is a characteristic feature of our planet, but estimates of how long it has been the modus operandi of lithospheric formation and interactions range from the Hadean to the Neoproterozoic. In this paper, we review sedimentary, igneous and metamorphic proxies along with palaeomagnetic data to infer both the development of rigid lithospheric plates and their independent relative motion, and conclude that significant changes in Earth behaviour occurred in the mid- to late Archaean, between 3.2 Ga and 2.5 Ga. These data include: sedimentary rock associations inferred to have accumulated in passive continental margin settings, marking the onset of sea-floor spreading; the oldest foreland basin deposits associated with lithospheric convergence; a change from thin, new continental crust of mafic composition to thicker crust of intermediate composition, increased crustal reworking and the emplacement of potassic and peraluminous granites, indicating stabilization of the lithosphere; replacement of dome and keel structures in granite-greenstone terranes, which relate to vertical tectonics, by linear thrust imbricated belts; the commencement of temporally paired systems of intermediate and high dT/dP gradients, with the former interpreted to represent subduction to collisional settings and the latter representing possible hinterland back-arc settings or ocean plateau environments. Palaeomagnetic data from the Kaapvaal and Pilbara cratons for the interval 2780-2710 Ma and from the Superior, Kaapvaal and Kola-Karelia cratons for 2700-2440 Ma suggest significant relative movements. We consider these changes in the behaviour and character of the lithosphere to be consistent with a gestational transition from a non-plate tectonic mode, arguably with localized subduction, to the onset of sustained plate tectonics.This article is part of a discussion meeting issue 'Earth dynamics and the development of plate tectonics'.", url = "https://doi.org/10.1098/rsta.2017.0405", doi = "10.1098/rsta.2017.0405", openalex = "W2894980515", references = "doi101016jgloplacha201610002, doi101016jgr201704001, doi101016jmarpetgeo201011002, doi101029tc005i003p00439, doi101130g354021" } @article{doi101016jgr201907009, author = "van Hinsbergen, Douwe J.J. and Torsvik, Trond H. and Schmid, Stefan M. and Maţenco, Liviu and Maffione, Marco and Vissers, Reinoud L.M. and Gürer, Derya and Spakman, Wim", title = "Orogenic architecture of the Mediterranean region and kinematic reconstruction of its tectonic evolution since the Triassic", year = "2019", journal = "Gondwana Research", abstract = "The basins and orogens of the Mediterranean region ultimately result from the opening of oceans during the early break-up of Pangea since the Triassic, and their subsequent destruction by subduction accommodating convergence between the African and Eurasian Plates since the Jurassic. The region has been the cradle for the development of geodynamic concepts that link crustal evolution to continental break-up, oceanic and continental subduction, and mantle dynamics in general. The development of such concepts requires a first-order understanding of the kinematic evolution of the region for which a multitude of reconstructions have previously been proposed. In this paper, we use advances made in kinematic restoration software in the last decade with a systematic reconstruction protocol for developing a more quantitative restoration of the Mediterranean region for the last 240 million years. This restoration is constructed for the first time with the GPlates plate reconstruction software and uses a systematic reconstruction protocol that limits input data to marine magnetic anomaly reconstructions of ocean basins, structural geological constraints quantifying timing, direction, and magnitude of tectonic motion, and tests and iterations against paleomagnetic data. This approach leads to a reconstruction that is reproducible, and updatable with future constraints. We first review constraints on the opening history of the Atlantic (and Red Sea) oceans and the Bay of Biscay. We then provide a comprehensive overview of the architecture of the Mediterranean orogens, from the Pyrenees and Betic-Rif orogen in the west to the Caucasus in the east and identify structural geological constraints on tectonic motions. We subsequently analyze a newly constructed database of some 2300 published paleomagnetic sites from the Mediterranean region and test the reconstruction against these constraints. We provide the reconstruction in the form of 12 maps being snapshots from 240 to 0 Ma, outline the main features in each time-slice, and identify differences from previous reconstructions, which are discussed in the final section.", url = "https://doi.org/10.1016/j.gr.2019.07.009", doi = "10.1016/j.gr.2019.07.009", openalex = "W2971609132", references = "doi1010022013rg000444, doi1010022013tc003349, doi101007s0053101410603, doi1010160040195181902754, doi101016004019518690199x, doi101016jearscirev201006002, doi101016jearscirev201203002, doi101016jearscirev201206007, doi101016jepsl200910032, doi101016jgr201907005, doi101016jpalaeo200402033, doi101016jtecto201305037, doi101016jtecto201710004, doi101016s0012821x0100588x, doi101016s0012821x03004527, doi1010179781316225523, doi1010292007gc001743, doi10102990tc02623, doi10102996tc00433, doi101029tc005i002p00227, doi101029tc008i001p00099, doi101029tc009i004p00641, doi101046j1365246x200301917x, doi101073pnas1117262109, doi101098rspa19530064, doi101111j1365246x1980tb02601x, doi101144gslsp19890450115, doi101146annurevearth32101802120415, doi1023073060311, doi103906yer100511, tenveen2003incipient" } @article{doi1010292018tc005462, author = "Müller, R. Dietmar and Zahirovic, Sabin and Williams, Simon and Cannon, John and Seton, Maria and Bower, Dan J. and Tetley, Michael G. and Heine, Christian and Breton, Eline Le and Liu, Shaofeng and Russell, Samuel H. J. and Yang, Ting and Leonard, Jonathon and Gurnis, Michael", title = "A Global Plate Model Including Lithospheric Deformation Along Major Rifts and Orogens Since the Triassic", year = "2019", journal = "Tectonics", abstract = "Abstract Global deep‐time plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global Mesozoic–Cenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at \textasciitilde 240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 × 10 6 km 2 in the Late Jurassic (\textasciitilde 160–155 Ma), driven by a vast network of rift systems. After a mid‐Cretaceous drop in deformation, it reaches a high of 48 x 10 6 km 2 in the Late Eocene (\textasciitilde 35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65\% extension and 35\% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plate‐mantle system.", url = "https://doi.org/10.1029/2018tc005462", doi = "10.1029/2018tc005462", openalex = "W2944227774", references = "doi1010022013eo450001, doi1010022013tc003349, doi1010022014gc005407, doi101007s0053101410603, doi101016004019519090116p, doi101016jearscirev201006002, doi101016jearscirev201206007, doi101016jgloplacha201610002, doi101016jjafrearsci200507019, doi1010292005jb004035, doi1010292018gc007584, doi101029jb073i006p01959, doi101029tc008i001p00099, doi1010382161276a0, doi101038s4156101700036, doi101046j1365246x200301917x, doi101144sp3281, doi101146annurevearth060115012211, doi105194se42152013" } @article{doi1010292019ea000658, author = "Tozer, B. and Sandwell, David T. and Smith, Walter H. F. and Olson, Christopher and Beale, J. and Wessel, Paul", title = "Global Bathymetry and Topography at 15 Arc Sec: SRTM15+", year = "2019", journal = "Earth and Space Science", abstract = "An updated global bathymetry and topography grid is presented using a spatial sampling interval of 15 arc sec. The bathymetry is produced using a combination of shipboard soundings and depths predicted using satellite altimetry. New data consists of >33.6 million multibeam and singlebeam measurements collated by several institutions, namely, the National Geospatial‐Intelligence Agency, Japan Agency for Marine‐Earth Science and Technology, Geoscience Australia, Center for Coastal and Ocean Mapping, and Scripps Institution of Oceanography. New altimetry data consists of 48, 14, and 12 months of retracked range measurements from Cryosat‐2, SARAL/AltiKa, and Jason‐2, respectively. With respect to SRTM15\_PLUS (Olson et al.,), the inclusion of these new data results in a ∼1.4‐km improvement in the minimum wavelength recovered for sea surface free‐air gravity anomalies, a small increase in the accuracy of altimetrically derived predicted depths, and a 1.24\% increase, from 9.60\% to 10.84\%, in the total area of ocean floor that is constrained by shipboard soundings at 15‐arc sec resolution. Bathymetric grid cells constrained by satellite altimetry have estimated uncertainties of ±150 m in the deep oceans and ±180 m between coastlines and the continental rise. Onshore, topography data are sourced from previously published digital elevation models, predominately SRTM‐CGIAR V4.1 between 60°N and 60°S. ArcticDEM is used above 60°N, while Reference Elevation Model of Antarctica is used below 62°S. Auxiliary grids illustrating shipboard data coverage, marine free‐air gravity anomalies, and vertical gradient gradients are also provided in common data formats.", url = "https://doi.org/10.1029/2019ea000658", doi = "10.1029/2019ea000658", openalex = "W2968914048", references = "doi1010292007gc001743, doi1010292018gc007584, doi10102996jb03223, doi101126science28454191495, doi10119011442837" } @article{doi101144sp470201958, author = "Wilson, Robert W. and Houseman, G. A. and Buiter, Susanne and McCaffrey, Ken and Doré, A. G.", title = "Fifty years of the Wilson Cycle concept in plate tectonics: an overview", year = "2019", journal = "Geological Society London Special Publications", abstract = "Abstract It is now more than 50 years since Tuzo Wilson published his paper asking ‘Did the Atlantic close and then re-open?’. This led to the ‘Wilson Cycle’ concept in which the repeated opening and closing of ocean basins along old orogenic belts is a key process in the assembly and breakup of supercontinents. This implied that the processes of rifting and mountain building somehow pre-conditioned and weakened the lithosphere in these regions, making them susceptible to strain localization during future deformation episodes. Here we provide a retrospective look at the development of the concept, how it has evolved over the past five decades, current thinking and future focus areas. The Wilson Cycle has proved enormously important to the theory and practice of geology and underlies much of what we know about the geological evolution of the Earth and its lithosphere. The concept will no doubt continue to be developed as we gain more understanding of the physical processes that control mantle convection and plate tectonics, and as more data become available from currently less accessible regions.", url = "https://doi.org/10.1144/sp470-2019-58", doi = "10.1144/sp470-2019-58", openalex = "W2963313004", references = "doi101016jgr201408006, doi101017cbo9780511612879, doi101029138gm06, doi1010292018gc007584, doi101029jb073i012p03661, doi101029jb073i018p05855, doi101029jb075i014p02625, doi101029jb085ib11p06248, doi101038199947a0, doi101038385219a0, doi10108014786441608635602, doi101130ges007271, openalexw2883478268" } @article{doi10247503201901, author = "Kapp, Paul and DeCelles, Peter G.", title = "Mesozoic–Cenozoic geological evolution of the Himalayan-Tibetan orogen and working tectonic hypotheses", year = "2019", journal = "American Journal of Science", abstract = "The Himalayan-Tibetan orogen culminated during the Cenozoic India -- Asia collision, but its geological framework and initial growth were fundamentally the result of multiple, previous ocean closure and intercontinental suturing events. As such, the Himalayan-Tibetan orogen provides an ideal laboratory to investigate geological signatures of the suturing process in general, and how the Earth9s highest and largest orogenic feature formed in specific. This paper synthesizes the Triassic through Cenozoic geology of the central Himalayan-Tibetan orogen and presents our tectonic interpretations in a time series of schematic lithosphere-scale cross-sections and paleogeographic maps. We suggest that north-dipping subducting slabs beneath Asian continental terranes associated with closure of the Paleo-, Meso-, and Neo-Tethys oceans experienced phases of southward trench retreat prior to intercontinental suturing. These trench retreat events created ophiolites in forearc extensional settings and/or a backarc oceanic basins between rifted segments of upper-plate continental margin arcs. This process may have occurred at least three times along the southern Asian margin during northward subduction of Neo-Tethys oceanic lithosphere: from ∼174 to 156 Ma; 132 to 120 Ma; and 90 to 70 Ma. At most other times, the Tibetan terranes underwent Cordilleran-style or collisional contractional deformation. Geological records indicate that most of northern and central Tibet (the Hoh-Xil and Qiangtang terranes, respectively) were uplifted above sea level by Jurassic time, and southern Tibet (the Lhasa terrane) north of its forearc region has been above sea level since ∼100 Ma. Stratigraphic evidence indicates that the northern Himalayan margin of India collided with an Asian-affinity subduction complex -- forearc -- arc system beginning at ∼60 Ma. Both the Himalaya (composed of Indian crust) and Tibet show continuous geological records of orogenesis since ∼60 Ma. As no evidence exists in the rock record for a younger suture, the simplest interpretation of the geology is that India -- Asia collision initiated at ∼60 Ma. Plate circuit, paleomagnetic, and structural reconstructions, however, suggest that the southern margin of Asia was too far north of India to have collided with it at that time. Seismic tomographic images are also suggestive of a second, more southerly Neo-Tethyan oceanic slab in the lower mantle where the northernmost margin of India may have been located at ∼60 Ma. The geology of Tibet and the India -- Asia suture zone permits an alternative collision scenario in which the continental margin arc along southern Asia (the Gangdese arc) was split by extension beginning at ∼90 Ma, and along with its forearc to the south (the Xigaze forearc), rifted southward and opened a backarc ocean basin. The rifted arc collided with India at ∼60 Ma whereas the hypothetical backarc ocean basin may not have been consumed until ∼45 Ma. A compilation of igneous age data from Tibet shows that the most recent phase of Gangdese arc magmatism in the southern Lhasa terrane initiated at ∼70 Ma, peaked at ∼51 Ma, and terminated at ∼38 Ma. Cenozoic potassic-adakitic magmatism initiated at ∼45 Ma within a ∼200-km-wide elliptical area within the northern Qiangtang terrane, after which it swept westward and southward with time across central Tibet until ∼26 Ma. At 26 to 23 Ma, potassic-adakitic magmatism swept southward across the Lhasa terrane, a narrow (∼20 km width), orogen-parallel basin developed at low elevation along the axis of the India -- Asia suture zone (the Kailas basin), and Greater Himalayan Sequence rocks began extruding southward between the South Tibetan Detachment and Main Central Thrust. The Kailas basin was then uplifted to \>4 km elevation by ∼20 Ma, after which parts of the India -- Asia suture zone and Gangdese arc experienced \>6 km of exhumation (between ∼20 and 16 Ma). Between ∼16 and 12 Ma, slip along the South Tibetan Detachment terminated and east-west extension initiated in the northern Himalaya and Tibet. Potassic-adakitic magmatism in the Lhasa terrane shows a northward younging trend in the age of its termination, beginning at 20 to 18 Ma until volcanism ended at 8 Ma. We interpret the post-45 Ma geological evolution in the context of the subduction dynamics of Indian continental lithosphere and its interplay with delamination of Asian mantle lithosphere.", url = "https://doi.org/10.2475/03.2019.01", doi = "10.2475/03.2019.01", openalex = "W2946391716", references = "doi1010022014tc003522, doi101002tect20057, doi101007s0019000600303, doi101016jearscirev201206007, doi101016jepsl200408019, doi101016jepsl201301023, doi101016jepsl201609003, doi101016jepsl201710041, doi101016jgr201207001, doi101016jjseaes201003008, doi101016jjseaes201409012, doi101016s0012821x99001314, doi101016s0012821x99002770, doi101016s0743954798000026, doi1010292010jb007673, doi1010292011tc002868, doi101029tc007i006p01123, doi101038332695a0, doi101038373055a0, doi101038414738a, doi101038ngeo1669, doi101073pnas1117262109, doi101130b253881, doi101130spe269, openalexw614437925" } @article{doi101016jearscirev2020103172, author = "Palin, Richard M. and Santosh, M. and Cao, Wentao and Li, Shan-Shan and Hernández‐Uribe, David and Parsons, Andrew J.", title = "Secular change and the onset of plate tectonics on Earth", year = "2020", journal = "Earth-Science Reviews", abstract = "The Earth as a planetary system has experienced significant change since its formation c. 4.54 Gyr ago. Some of these changes have been gradual, such as secular cooling of the mantle, and some have been abrupt, such as the rapid increase in free oxygen in the atmosphere at the Archean–Proterozoic transition. Many of these changes have directly affected tectonic processes on Earth and are manifest by temporal trends within the sedimentary, igneous, and metamorphic rock record. Indeed, the timing of global onset of mobile-lid (subduction-driven) plate tectonics on our planet remains one of the fundamental points of debate within the geosciences today, and constraining the age and cause of this transition has profound implications for understanding our own planet's long-term evolution, and that for other rocky bodies in our solar system. Interpretations based on various sources of evidence have led different authors to propose a very wide range of ages for the onset of subduction-driven tectonics, which span almost all of Earth history from the Hadean to the Neoproterozoic, with this uncertainty stemming from the varying reliability of different proxies. Here, we review evidence for paleo-subduction preserved within the geological record, with a focus on metamorphic rocks and the geodynamic information that can be derived from them. First, we describe the different types of tectonic/geodynamic regimes that may occur on Earth or any other silicate body, and then review different models for the thermal evolution of the Earth and the geodynamic conditions necessary for plate tectonics to stabilize on a rocky planet. The community's current understanding of the petrology and structure of Archean and Proterozoic oceanic and continental crust is then discussed in comparison with modern-day equivalents, including how and why they differ. We then summarize evidence for the operation of subduction through time, including petrological (metamorphic), tectonic, and geochemical/isotopic data, and the results of petrological and geodynamical modeling. The styles of metamorphism in the Archean are then examined and we discuss how the secular distribution of metamorphic rock types can inform the type of geodynamic regime that operated at any point in time. In conclusion, we argue that most independent observations from the geological record and results of lithospheric-scale geodynamic modeling support a global-scale initiation of plate tectonics no later than c. 3 Ga, just preceding the Archean–Proterozoic transition. Evidence for subduction in Early Archean terranes is likely accounted for by localized occurrences of plume-induced subduction initiation, although these did not develop into a stable, globally connected network of plate boundaries until later in Earth history. Finally, we provide a discussion of major unresolved questions related to this review's theme and provide suggested directions for future research.", url = "https://doi.org/10.1016/j.earscirev.2020.103172", doi = "10.1016/j.earscirev.2020.103172", openalex = "W3026193896", references = "doi1010160012821x94900825, doi101016jgr201212023, doi101016jgr201212026, doi101016jgr201704001, doi101016jgr201704011, doi101016jgsf201812007, doi101016jmarpetgeo201105008, doi10108000206810903557704" } @article{doi1010292019jb018774, author = "Wang, Min and Shen, Zheng‐Kang", title = "Present‐Day Crustal Deformation of Continental China Derived From GPS and Its Tectonic Implications", year = "2020", journal = "Journal of Geophysical Research Solid Earth", abstract = "Abstract We process rigorously GPS data observed during the past 25 years from continental China to derive site secular velocities. Analysis of the velocity solution leads to the following results. (a) The deformation field inside the Tibetan plateau and Tien Shan is predominantly continuous, and large deformation gradients only exist perpendicular to the Indo‐Eurasian relative plate motion and are associated with a few large strike‐slip faults. (b) Lateral extrusions occur on both the east and west sides of the plateau. The westward extrusion peaks at \textasciitilde 6 mm/yr in the Pamir‐Hindu Kush region. A bell‐shaped eastward extrusion involves most of the plateau at a maximum rate of \textasciitilde 20 mm/yr between the Jiali and Ganzi‐Yushu faults, and the pattern is consistent with gravitational flow in southern and southeastern Tibet where the crust shows widespread dilatation at 10–20 nanostrain/yr. (c) The southeast borderland of Tibet rotates clockwise around the eastern Himalaya syntaxis, with sinistral and dextral shear motions along faults at the outer and inner flanks of the rotation terrane. The result suggests gravitational flow accomplished through rotation and translation of smaller subblocks in the upper crust. (d) Outside of the Tibetan plateau and Tien Shan, deformation field is block‐like. However, unnegligible internal deformation on the order of a couple of nanostrain/yr is found for all blocks. The North China block, under a unique tectonic loading environment, deforms and rotates at rates significantly higher than its northern and southern neighboring blocks, attesting its higher seismicity rate and earthquake hazard potential than its neighbors.", url = "https://doi.org/10.1029/2019jb018774", doi = "10.1029/2019jb018774", openalex = "W2999289209", references = "doi101002grl50288, doi101007s0019000600303, doi1010160012821x81901898, doi1010292001gc000252, doi1010292005gl025546, doi1010292011jb008930, doi101038386061a0, doi101126science2765313788" } @article{doi101073pnas2012215118, author = "Thomson, Robert C. and Spinks, Phillip Q. and Shaffer, H. Bradley", title = "A global phylogeny of turtles reveals a burst of climate-associated diversification on continental margins", year = "2021", journal = "Proceedings of the National Academy of Sciences", abstract = "Living turtles are characterized by extraordinarily low species diversity given their age. The clade's extensive fossil record indicates that climate and biogeography may have played important roles in determining their diversity. We investigated this hypothesis by collecting a molecular dataset for 591 individual turtles that, together, represent 80\% of all turtle species, including representatives of all families and 98\% of genera, and used it to jointly estimate phylogeny and divergence times. We found that the turtle tree is characterized by relatively constant diversification (speciation minus extinction) punctuated by a single threefold increase. We also found that this shift is temporally and geographically associated with newly emerged continental margins that appeared during the Eocene-Oligocene transition about 30 million years before present. In apparent contrast, the fossil record from this time period contains evidence for a major, but regional, extinction event. These seemingly discordant findings appear to be driven by a common global process: global cooling and drying at the time of the Eocene-Oligocene transition. This climatic shift led to aridification that drove extinctions in important fossil-bearing areas, while simultaneously exposing new continental margin habitat that subsequently allowed for a burst of speciation associated with these newly exploitable ecological opportunities.", url = "https://doi.org/10.1073/pnas.2012215118", doi = "10.1073/pnas.2012215118", openalex = "W3127436575", references = "doi101016jympev201705008, doi1010292018gc007584, doi10166612149" } @article{doi101016jearscirev2022104069, author = "Hasterok, Derrick and Halpin, JA and Collins, Alan S. and Hand, Martin and Kreemer, Corné and Gard, Matthew and Glorie, Stijn", title = "New Maps of Global Geological Provinces and Tectonic Plates", year = "2022", journal = "Earth-Science Reviews", url = "https://doi.org/10.1016/j.earscirev.2022.104069", doi = "10.1016/j.earscirev.2022.104069", openalex = "W4283390639", references = "doi101016jearscirev2020103477, doi101016jearscirev2021103700, doi101016jgr201704011, doi101016jgr201907005, doi101016jgsf201111008, doi101016jprecamres201411023, doi101016jprecamres2021106463, doi101016s0040195103003378, doi101144gslmem20060320101" } @article{doi101016jgr202207014, author = "van der Meer, Douwe G. and Scotese, Christopher R. and Mills, Benjamin and Sluijs, Appy and van den Berg van Saparoea, Aart-Peter and van de Weg, Ruben M.B.", title = "Long-term Phanerozoic global mean sea level: Insights from strontium isotope variations and estimates of continental glaciation", year = "2022", journal = "Gondwana Research", abstract = "Global mean sea level is a key component within the fields of climate and oceanographic modelling in the Anthropocene. Hence, an improved understanding of eustatic sea level in deep time aids in our understanding of Earth’s paleoclimate and may help predict future climatological and sea level changes. However, long-term eustatic sea level reconstructions are hampered because of ambiguity in stratigraphic interpretations of the rock record and limitations in plate tectonic modelling. Hence the amplitude and timescales of Phanerozoic eustasy remains poorly constrained. A novel, independent method from stratigraphic or plate modelling methods, based on estimating the effect of plate tectonics (i.e., mid-ocean ridge spreading) from the 87Sr/86Sr record led to a long-term eustatic sea level curve, but did not include glacio-eustatic drivers. Here, we incorporate changes in sea level resulting from variations in seawater volume from continental glaciations at time steps of 1 Myr. Based on a recent compilation of global average paleotemperature derived from δ18O data, paleo-Köppen zones and paleogeographic reconstructions, we estimate ice distribution on land and continental shelf margins. Ice thickness is calibrated with a recent paleoclimate model for the late Cenozoic icehouse, yielding an average ∼1.4 km thickness for land ice, ultimately providing global ice volume estimates. Eustatic sea level variations associated with long-term glaciations (>1 Myr) reach up to ∼90 m, similar to, and is at times dominant in amplitude over plate tectonic-derived eustasy. We superimpose the long-term sea level effects of land ice on the plate tectonically driven sea level record. This results in a Tectono-Glacio-Eustatic (TGE) curvefor which we describe the main long-term (>50 Myr) and residual trends in detail.", url = "https://doi.org/10.1016/j.gr.2022.07.014", doi = "10.1016/j.gr.2022.07.014", openalex = "W4289745731", references = "doi1010160012825287900626, doi101017s0016756818000110, doi101146annurevearth081320064052, doi105194cp1714832021" } @article{doi101073pnas2120662119, author = "Tietje, Melanie and Antonelli, Alexandre and Baker, William J. and Govaerts, Rafaël and Smith, Stephen A. and Eiserhardt, Wolf L.", title = "Global variation in diversification rate and species richness are unlinked in plants", year = "2022", journal = "Proceedings of the National Academy of Sciences", abstract = {Species richness varies immensely around the world. Variation in the rate of diversification (speciation minus extinction) is often hypothesized to explain this pattern, while alternative explanations invoke time or ecological carrying capacities as drivers. Focusing on seed plants, the world's most important engineers of terrestrial ecosystems, we investigated the role of diversification rate as a link between the environment and global species richness patterns. Applying structural equation modeling to a comprehensive distribution dataset and phylogenetic tree covering all circa 332,000 seed plant species and 99.9\% of the world's terrestrial surface (excluding Antarctica), we test five broad hypotheses postulating that diversification serves as a mechanistic link between species richness and climate, climatic stability, seasonality, environmental heterogeneity, or the distribution of biomes. Our results show that the global patterns of species richness and diversification rate are entirely independent. Diversification rates were not highest in warm and wet climates, running counter to the Metabolic Theory of Ecology, one of the dominant explanations for global gradients in species richness. Instead, diversification rates were highest in edaphically diverse, dry areas that have experienced climate change during the Neogene. Meanwhile, we confirmed climate and environmental heterogeneity as the main drivers of species richness, but these effects did not involve diversification rates as a mechanistic link, calling for alternative explanations. We conclude that high species richness is likely driven by the antiquity of wet tropical areas (supporting the "tropical conservatism hypothesis") or the high ecological carrying capacity of warm, wet, and/or environmentally heterogeneous environments.}, url = "https://doi.org/10.1073/pnas.2120662119", doi = "10.1073/pnas.2120662119", openalex = "W4283692830", references = "doi101017cbo9780511623387, doi1010371082989x1116, doi10103835012228, doi101038nature11631, doi101073pnas1711842115, doi101086283438, doi101146annurevearth081320064052, doi1016410006356820010510933teotwa20co2, doi101890038006, doi101890039000, doi1023071269470, doi1023072989767, hofmann2019diversity" } @article{doi101073pnas2203818119, author = "Landwehrs, Jan and Feulner, Georg and Willeit, Matteo and Petri, Stefan and Sames, Benjamin and Wagreich, Michael and Whiteside, Jessica H and Olsen, Paul E", title = "Modes of Pangean lake level cyclicity driven by astronomical climate pacing modulated by continental position and pCO[Formula: see text].", year = "2022", journal = "Proceedings of the National Academy of Sciences of the United States of America", abstract = "Orbital cyclicity is a fundamental pacemaker of Earth's climate system. The Newark-Hartford Basin (NHB) lake sediment record of eastern North America contains compelling geologic expressions of this cyclicity, reflecting variations of climatic conditions in tropical Pangea during the Late Triassic and earliest Jurassic (\textasciitilde 233 to 199 Ma). Climate modeling enables a deeper mechanistic understanding of Earth system modulation during this unique greenhouse and supercontinent period. We link major features of the NHB record to the combined climatic effects of orbital forcing, paleogeographic changes, and atmospheric pCO[Formula: see text] variations. An ensemble of transient, orbitally driven climate simulations is assessed for nine time slices, three atmospheric pCO[Formula: see text] values, and two paleogeographic reconstructions. Climatic transitions from tropical humid to more seasonal and ultimately semiarid are associated with tectonic drift of the NHB from [Formula: see text] to [Formula: see text]. The modeled orbital modulation of the precipitation-evaporation balance is most pronounced during the 220 to 200 Ma interval, whereas it is limited by weak seasonality and increasing aridity before and after this interval. Lower pCO[Formula: see text] at around 205 Ma contributes to drier climates and could have led to the observed damping of sediment cyclicity. Eccentricity-modulated precession dominates the orbitally driven climate response in the NHB region. High obliquity further amplifies summer precipitation through the seasonal shifts in the tropical rainfall belt. Regions with other proxy records are also assessed, providing guidance toward an integrated picture of global astronomical climate forcing in the Late Triassic and ultimately of other periods in Earth history.", url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC9674254/", doi = "10.1073/pnas.2203818119", openalex = "W4308430174", pmcid = "PMC9674254", pmid = "36343239", references = "doi1010292010gl045777, doi101029jd094id03p03341, doi101038ncomms14845, doi101038sdata2018214, doi101086321493, doi101086648217, doi101126science1234204, doi101126science19442701121, doi101126science2344778842, doi101126science2845414616" } @article{doi105194se1311272022, author = "Müller, R. Dietmar and Flament, Nicolas and Cannon, John and Tetley, Michael G. and Williams, Simon and Cao, Xianzhi and Bodur, Ömer F. and Zahirovic, Sabin and Merdith, Andrew", title = "A tectonic-rules-based mantle reference frame since 1 billion years ago – implications for supercontinent cycles and plate–mantle system evolution", year = "2022", journal = "Solid Earth", abstract = "Abstract. Understanding the long-term evolution of Earth's plate–mantle system is reliant on absolute plate motion models in a mantle reference frame, but such models are both difficult to construct and controversial. We present a tectonic-rules-based optimization approach to construct a plate motion model in a mantle reference frame covering the last billion years and use it as a constraint for mantle flow models. Our plate motion model results in net lithospheric rotation consistently below 0.25∘ Myr−1, in agreement with mantle flow models, while trench motions are confined to a relatively narrow range of −2 to +2 cm yr−1 since 320 Ma, during Pangea stability and dispersal. In contrast, the period from 600 to 320 Ma, nicknamed the “zippy tricentenary” here, displays twice the trench motion scatter compared to more recent times, reflecting a predominance of short and highly mobile subduction zones. Our model supports an orthoversion evolution from Rodinia to Pangea with Pangea offset approximately 90∘ eastwards relative to Rodinia – this is the opposite sense of motion compared to a previous orthoversion hypothesis based on paleomagnetic data. In our coupled plate–mantle model a broad network of basal mantle ridges forms between 1000 and 600 Ma, reflecting widely distributed subduction zones. Between 600 and 500 Ma a short-lived degree-2 basal mantle structure forms in response to a band of subduction zones confined to low latitudes, generating extensive antipodal lower mantle upwellings centred at the poles. Subsequently, the northern basal structure migrates southward and evolves into a Pacific-centred upwelling, while the southern structure is dissected by subducting slabs, disintegrating into a network of ridges between 500 and 400 Ma. From 400 to 200 Ma, a stable Pacific-centred degree-1 convective planform emerges. It lacks an antipodal counterpart due to the closure of the Iapetus and Rheic oceans between Laurussia and Gondwana as well as due to coeval subduction between Baltica and Laurentia and around Siberia, populating the mantle with slabs until 320 Ma when Pangea is assembled. A basal degree-2 structure forms subsequent to Pangea breakup, after the influence of previously subducted slabs in the African hemisphere on the lowermost mantle structure has faded away. This succession of mantle states is distinct from previously proposed mantle convection models. We show that the history of plume-related volcanism is consistent with deep plumes associated with evolving basal mantle structures. This Solid Earth Evolution Model for the last 1000 million years (SEEM1000) forms the foundation for a multitude of spatio-temporal data analysis approaches.", url = "https://doi.org/10.5194/se-13-1127-2022", doi = "10.5194/se-13-1127-2022", openalex = "W4284882642", references = "doi101016jearscirev2020103463, doi101016jearscirev2020103477" } @article{doi101144sp544202428, author = "Scotese, Christopher R. and Vérard, Christian and Burgener, Landon and Elling, Reece P. and Kocsis, Ádám T.", title = "The Cretaceous world: plate tectonics, palaeogeography and palaeoclimate", year = "2024", journal = "Geological Society London Special Publications", abstract = "The tectonics, geography and climate of the Cretaceous world were very different from the modern world. At the start of the Cretaceous, the supercontinent of Pangaea had just begun to break apart and only a few small ocean basins separated Laurasia, West Gondwana and East Gondwana. Unlike the modern world, there were no significant continent–continent collisions during the Cretaceous, and the continents were low-lying and easily flooded. The transition from a Pangaea-like configuration to a more dispersed continental arrangement had important effects on the global sea level and climate. During the Early Cretaceous, as the continents rifted apart, the new continental rifts were transformed into young ocean basins. The oceanic lithosphere in these young ocean basins was thermally elevated, which boosted sea level. Sea level, on average, was c. 70 m higher than that of the present day. Sea level was highest during the mid-Cretaceous (90–80 Ma), with a subsidiary peak occurring c. 120 Myr ago (early Aptian). Overall, the Cretaceous was much warmer than the present-day climate (>10°C warmer). These very warm times produced oceanic anoxic events (OAEs), and the high temperatures in equatorial regions sometimes made terrestrial and shallow-marine ecosystems uninhabitable (temperatures >40°C). This is unlike anything we have seen in the last 35 Myr and may presage the eventual results of man-made global warming. This mostly stable, hot climate regime endured for nearly 80 Myr before dramatically terminating with the Chicxulub bolide impact 66 Myr ago. Temperatures plummeted to icehouse levels in the ‘impact winter’ as a result of sunlight-absorbing dust and aerosols being thrown into the atmosphere. As a consequence of the collapse of the food chain, c. 75\% of all species were wiped out. The effect of this extinction event on global ecosystems was second only to the great Permo-Triassic Extinction.", url = "https://doi.org/10.1144/sp544-2024-28", doi = "10.1144/sp544-2024-28", openalex = "W4396610374", references = "alvarez1980extraterrestrial, doi1010160012825272901316, doi101016004019518590006x, doi101016jcub202111061, doi101016jearscirev2020103463, doi101017s0016756818000110, doi101038nature06588, doi101038s41467018039961, doi101086608138, doi101098rspa19530064, doi101111j1365246x1991tb06724x, doi101126science1059412, doi101126science1894201419, doi101126science23547931156, doi101126science27753341956, doi101126scienceadi5177, doi101144001676492006022, doi101146annurevearth081320064052, doi105194cp1714832021, doi105860choice353862, openalexw1520428197, openalexw1607828269" } @article{doi1010292025gl116752, author = "Xu, W. L. and Song, Bo and Shi, Jizhong and Li, Yan and Wang, Baowen and Ye, Xiaozhou and Han, Xiaofeng and Xu, Haihong and Zhang, Yunpeng and Zhang, Huiyuan and Sun, Zhiming", title = "New Permian Paleomagnetic and Geochronologic Results From the Alxa Block: Constraints on Its Tectonic Affinity and the Closure of Paleo‐Asian Ocean", year = "2025", journal = "Geophysical Research Letters", abstract = "Abstract The Paleo‐Asian Ocean's (PAO) closure timing and the Alxa Block's (ALB) tectonic affinity remain debated. We present new paleomagnetic and geochronologic data from Permian volcanic and sedimentary rocks in the ALB. Characteristic remanent magnetization (ChRM) directions from Early (∼282 Ma), Middle (∼268 Ma), and Late Permian (∼255 Ma) rocks pass fold, reversals, and conglomerate tests, confirming their primary origin. These results yield the first reliable Permian paleopoles for the ALB. The data indicate minor movement during the Early–Middle Permian, followed by rapid northward drift and ∼53.8° counterclockwise rotation in the Middle‐Late Permian. Comparison with surrounding blocks suggests the ALB was tectonically linked to North China but independent of Tarim. A significant paleolatitudinal gap between North China–ALB and Siberian–South Mongolia blocks during the Late Carboniferous–Middle Permian implies a wide mid‐eastern PAO, which closed during the Late Permian. These findings refine Permian paleogeographic reconstructions of Eastern Asia.", url = "https://doi.org/10.1029/2025gl116752", doi = "10.1029/2025gl116752", openalex = "W4415153984", references = "doi101016jearscirev201206007, doi101016jearscirev201709020, doi101016jgr201603013, doi101016jjseaes200711005, doi101016jlithos201004014, doi101038s41467024558048, doi101111j1365246x1964tb06300x, doi101111j1365246x1980tb02601x, doi101111j1365246x1990tb01761x, doi101111j1365246x1990tb05683x, doi101111j1751908x2004tb00755x" } @article{doi1010292025gl117395, author = "Gao, Biao and Xu, Guozhen and Yang, Wen‐Li and Chen, Jitao", title = "Disentangling Continental Weathering During the Late Paleozoic Ice Age", year = "2025", journal = "Geophysical Research Letters", abstract = "Abstract The consumption of atmospheric CO 2 through continental weathering played a critical role in shaping the evolution of the late Paleozoic Ice Age (LPIA), presumably driven by the Hercynian orogeny and the evolution of terrestrial plants. However, the relative impacts of these two major drivers to continental weathering remain poorly constrained. The South China Block was located near the paleo‐equator under a relatively stable tectonic setting during the late Paleozoic, and therefore provides valuable insights into silicate weathering dynamics. Here, we report a 60‐Myr‐long record of the chemical index of alteration (CIA) from a continuously deposited slope succession in South China. By integrating existing records of weathering proxies, we concluded that the Hercynian orogeny played an overwhelming role in enhanced silicate weathering rates during 333–291 Ma, whereas paleotropical forest ecosystems demonstrated their significant influences on weathering patterns during their rapid expansion phase (333–316 Ma).", url = "https://doi.org/10.1029/2025gl117395", doi = "10.1029/2025gl117395", openalex = "W4414809419", references = "doi101007bf00375192, doi1010160016703784904083, doi101016jgca200309012, doi101016jjseaes201212020, doi101016jprecamres201209017, doi101017cbo9780511628948, doi101017s0016756800058581, doi101038s41467024558048, doi1011300091761319950230921uteopm23co2, doi101146annurevearth281611, doi102475ajs2837641" } @article{doi101038s41467024558048, author = "Ren, Qiang and Zhang, Shihong and Hou, Mingcai and Zheng, Dongyu and Wu, Huaichun and Yang, Tianshui and Li, Haiyan and Chen, Anqing and Ogg, James G", title = "Continental drift triggered the Early Permian aridification of North China.", year = "2025", journal = "Nature communications", abstract = "The boundary between wet and arid climate zones in the Tethys Ocean remains challenging to trace, complicating our understanding of global aridification pattern during the Late Carboniferous to Early Permian transition. The North China Block (NCB), situated in the Tethys Ocean, underwent a transition from humid to arid climate during the Early Permian, providing a rare opportunity to trace this climate boundary across this region. Here, we present paleomagnetic evidence indicating that the NCB underwent rapid northward drift between 290 and 281 million years ago. The NCB's movement from a tropical wet to a subtropical arid zone corresponds to a lithological change from coal-bearing to red-bed deposits, demonstrating tectonic drift into a subtropical arid zone as the main driver of aridification in the NCB during this period. This drift also delineates the wet-dry boundary over the Tethys Ocean, consistent with modern climatic zonation patterns.", url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC11699124/", doi = "10.1038/s41467-024-55804-8", openalex = "W4406032481", pmcid = "PMC11699124", pmid = "39753587", references = "doi101007bf03184122, doi101016jearscirev201206007, doi101016s000925410200195x, doi1010292011tc002868, doi101029gl017i002p00159, doi101093petrologyegp082, doi101098rspa19530064, doi101111j1365246x1964tb06300x, doi101111j1365246x1980tb02601x, doi101111j1365246x1990tb05683x" }