@article{doi101038199947a0,
    author = "Vine, F. J. and Matthews, D. H.",
    title = "Magnetic Anomalies Over Oceanic Ridges",
    year = "1963",
    journal = "Nature",
    url = "https://doi.org/10.1038/199947a0",
    doi = "10.1038/199947a0",
    openalex = "W1978185779",
    references = "doi1010160146631353900069, doi101017s0016756800065730, doi101029jz067i002p00805, doi101029jz067i010p03997, doi101029jz068i003p00955, doi101038190854a0, doi101038197888a0, doi1010381981049a0, doi101111j1365246x1958tb05341x, doi101130001676061961721259msotwc20co2"
}

@article{doi101038201591a0,
    author = "Backus, George E.",
    title = "Magnetic Anomalies over Oceanic Ridges",
    year = "1964",
    journal = "Nature",
    url = "https://doi.org/10.1038/201591a0",
    doi = "10.1038/201591a0",
    openalex = "W2089264656"
}

@article{doi101126science1503695482,
    author = "Wilson, J. Tuzo",
    title = "Transform Faults, Oceanic Ridges, and Magnetic Anomalies Southwest of Vancouver Island",
    year = "1965",
    journal = "Science",
    abstract = {The San Andreas Fault and a large fault off British Columbia are interpreted as examples of the recently proposed "transform faults." They are joined by a short, isolated length of oceanic ridge striking N20 degrees E, with an associated "window" of young crust. The displacement along these faults is estimated at 400 kilometers.},
    url = "https://doi.org/10.1126/science.150.3695.482",
    doi = "10.1126/science.150.3695.482",
    openalex = "W2120909089"
}

@article{doi101126science1533739990,
    author = "Brace, W. F. and Byerlee, J. D.",
    title = "Stick-Slip as a Mechanism for Earthquakes",
    year = "1966",
    journal = "Science",
    abstract = "Stick-slip often accompanies frictional sliding in laboratory experi ments with geologic materials. Shallow focus earthquakes may represent stick slip during sliding along old or newly formed faults in the earth In such a situation, observed stress drops repre sent release of a small fraction of the stress supported by the rock surround ing the earthquake focus.",
    url = "https://doi.org/10.1126/science.153.3739.990",
    doi = "10.1126/science.153.3739.990",
    openalex = "W1970664646"
}

@article{doi101029jz072i008p02131,
    author = "Sykes, Lynn R.",
    title = "Mechanism of earthquakes and nature of faulting on the mid-oceanic ridges",
    year = "1967",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "The mechanisms of 17 earthquakes on the mid-oceanic ridges and their continental extensions were investigated using data from the World-Wide Standardized Seismograph Network of the U. S. Coast and Geodetic Survey and from other long-period seismograph instruments. Mechanism solutions of high precision can now be obtained for a large number of earthquakes with magnitudes as small as 6 in many areas of the world. Less than 1\% of the data used in this study are inconsistent with a quadrant distribution of first motions of the phases P and PKP; in many previous investigations 15 to 20\% of the data were often inconsistent with the published solutions. Ten of the earthquakes that were studied occurred on fracture zones that intersect the crest of the mid-oceanic ridge. The mechanism of each of the shocks that is located on a fracture zone is characterized by a predominance of strike-slip motion on a steeply dipping plane; the strike of one of the nodal planes for P waves is nearly coincident with the strike of the fracture zone. The sense of strike-slip motion in each of the ten solutions is in agreement with that predicted for transform faults; it is opposite to that expected for a simple offset of the ridge crest along the various fracture zones. The spatial distribution of earthquakes along fracture zones also seems to rule out the hypothesis of simple offset. Two well documented solutions for earthquakes that are located on the mid-Atlantic ridge but that do not appear to be located on fracture zones are characterized by a predominance of normal faulting. The mechanisms of four earthquakes on extensions of the mid-oceanic ridge system—one near northern Siberia and three in East Africa—are also characterized by a predominance of normal faulting. The inferred axes of maximum tension for these six events are approximately perpendicular to the strike of the mid-oceanic ridge system. The results are in agreement with hypotheses of sea-floor growth at the crest of the mid-oceanic ridge system.",
    url = "https://doi.org/10.1029/jz072i008p02131",
    doi = "10.1029/jz072i008p02131",
    openalex = "W1974493245",
    references = "doi1010160025322764900489, doi1010160040195164900101, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi101126science15437531164, doi101126science15437551405, doi101130petrologic1962599, doi101130spe65p1, doi105408002213687121"
}

@article{sykes1967mechanism,
    author = "Sykes, Lynn R.",
    title = "Mechanism of earthquakes and nature of faulting on the mid-oceanic ridges",
    year = "1967",
    journal = "Journal of Geophysical Research",
    url = "https://doi.org/10.1029/jz072i008p02131",
    doi = "10.1029/jz072i008p02131",
    number = "8",
    openalex = "W1974493245",
    pages = "2131-2153",
    volume = "72",
    references = "doi1010160025322764900489, doi1010160040195164900101, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi101126science15437531164, doi101126science15437551405, doi101130petrologic1962599, doi101130spe65p1, doi101785bssa0350040175, doi105408002213687121"
}

@article{sykes1967mechanism1,
    author = "Sykes, L. R",
    title = "Mechanism of earthquakes and nature of faulting on the mid- oceanic ridges",
    year = "1967",
    journal = "Journal of Geophysical Research, v. 72, p. 2131-2153",
    note = "talkorigins\_source = {true}; raw\_reference = {Sykes, L. R., 1967, Mechanism of earthquakes and nature of faulting on the mid- oceanic ridges: Journal of Geophysical Research, v. 72, p. 2131-2153.}"
}

@article{doi101029jb074i008p02049,
    author = "Scholz, Christian and Wyss, Max and Smith, Stewart W.",
    title = "Seismic and aseismic slip on the San Andreas Fault",
    year = "1969",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Field and experimental evidence are combined to deduce the mechanism of slip on shallow continental transcurrent faults, such as the San Andreas in California. Several lines of evidence portray the central section of the San Andreas fault as a very smooth and fiat surface, with a very low frictional strength in comparison to the breaking strength of intact rock. The Parkfield earthquake of June 27, 1966, and its aftershock and creep sequences are examined as a detailed example of fault slippage that includes both types, seismic and aseismic. It is shown from considerable number of field data that during the main shock a region from about 4 to 10 km in depth slipped approximately 30 cm. In response to this slippage, creep and aftershocks were generated. The creep and aftershocks are not directly interrelated, but they are microscopically identical processes of time-dependent brittle friction occurring in parallel in different regions. The creep occurred by time-dependent stable frictional sliding in the 4-km-thick surface layer; the aftershocks, by time-dependent stick-slip at the ends of the initial slipped zone. This model is in good agreement with laboratory results which show that slippage should occur by stable (aseismic) friction in the upper 4 km, by stick-slip accompanied by earthquakes from about 4 to 12 km, and by stable sliding or plastic friction below 12 km on the fault. One feature not observed in the laboratory is the episodic nature of creep. These episodes can be predicted with an accuracy of about I week.",
    url = "https://doi.org/10.1029/jb074i008p02049",
    doi = "10.1029/jb074i008p02049",
    openalex = "W1994518237"
}

@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{doi101029rg009i001p00103,
    author = "Isacks, Bryan L. and Molnár, Péter",
    title = "Distribution of stresses in the descending lithosphere from a global survey of focal‐mechanism solutions of mantle earthquakes",
    year = "1971",
    journal = "Reviews of Geophysics",
    abstract = "A region‐by‐region analysis of 204 reliable focal‐mechanism solutions for deep and intermediate‐depth earthquakes strongly supports the idea that portions of the lithosphere that descend into the mantle are slablike stress guides that align the earthquake‐generating stresses parallel to the inclined seismic zones. At intermediate depths extensional stresses parallel to the dip of the zone are predominant in zones characterized either by gaps in the seismicity as a function of depth or by an absence of deep earthquakes. Compressional stresses parallel to the dip of the zone are prevalent everywhere the zone exists below about 300 km. These results indicate that the lithosphere sinks into the asthenosphere under its own weight but encounters resistance to its downward motion below about 300 km. Additional results indicate contortions and disruptions of the descending slabs; however, stresses attributable to simple bending of the plates do not seem to be important in the generation of subcrustal earthquakes. This summary, intended to be comprehensive, includes nearly all solutions obtainable from the World‐Wide Standardized Seismograph Network (WWSSN) for the period 1962 through part of 1968 plus a selection of reliable solutions of pre‐1962 events, and it includes data from nearly every region in the world where earthquakes occur in the mantle. The double‐couple or shear dislocation model of the source mechanism is adequate for all the data.",
    url = "https://doi.org/10.1029/rg009i001p00103",
    doi = "10.1029/rg009i001p00103",
    openalex = "W2127454332",
    references = "doi101029jb073i006p01959, doi101029jb073i012p03661, doi101029jb073i018p05855, doi101029jb073i022p07089, doi101029jz070i016p03965, doi1010382161276a0, doi101038224125a0, doi101038226239a0, doi101111j1365246x1969tb00259x, doi101130001676061969801639totcam20co2, doi101785bssa0590010369, doi1023071790758, doi102307211302, openalexw623436458"
}

@misc{doi1010029781118782149ch1,
    author = "Sykes, Lynn R.",
    title = "Mechanism of Earthquakes and Nature of Faulting on the Mid‐Oceanic Ridges",
    year = "1972",
    booktitle = "Collected reprint series",
    abstract = "This chapter contains sections titled: Introduction Previous Mechanism Solutions for Earthquakes on the Mid-Oceanic Ridges Analysis of Data Presentation of Data for the Mid-Oceanic Ridges Extensions of the Mid-Oceanic Ridges East Pacific Rise Comparison of Inferred Mechanisms with those Deduced by Other Investigators Conclusions and Discussion References",
    url = "https://doi.org/10.1002/9781118782149.ch1",
    doi = "10.1002/9781118782149.ch1",
    openalex = "W4249400877",
    references = "doi1010160025322764900489, doi1010160040195164900101, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi101126science15437531164, doi101126science15437551405, doi101130spe65p1, doi101785bssa0350040175, doi105408002213687121"
}

@misc{sykes1972mechanism,
    author = "Sykes, Lynn R.",
    title = "Mechanism of Earthquakes and Nature of Faulting on the Mid‐Oceanic Ridges",
    year = "1972",
    booktitle = "Collected Reprint Series",
    url = "https://doi.org/10.1002/9781118782149.ch1",
    doi = "10.1002/9781118782149.ch1",
    openalex = "W4249400877",
    pages = "2131-2153",
    references = "doi1010160025322764900489, doi1010160040195164900101, doi101038190854a0, doi101038199947a0, doi101038207343a0, doi101126science15437531164, doi101126science15437551405, doi101130spe65p1, doi101785bssa0350040175, doi105408002213687121"
}

@article{doi101144gsjgs13330191,
    author = "Sibson, Richard H.",
    title = "Fault rocks and fault mechanisms",
    year = "1977",
    journal = "Journal of the Geological Society",
    abstract = "Physical factors likely to affect the genesis of the various fault rocks—frictional properties, temperature, effective stress normal to the fault and differential stress—are examined in relation to the energy budget of fault zones, the main velocity modes of faulting and the type of faulting, whether thrust, wrench, or normal. In a conceptual model of a major fault zone cutting crystalline quartzo-feldspathic crust, a zone of elastico-frictional (EF) behaviour generating random-fabric fault rocks (gouge—breccia—cataclasite series—pseudotachylyte) overlies a region where quasi-plastic (QP) processes of rock deformation operate in ductile shear zones with the production of mylonite series rocks possessing strong tectonite fabrics. In some cases, fault rocks developed by transient seismic faulting can be distinguished from those generated by slow aseismic shear. Random-fabric fault rocks may form as a result of seismic faulting within the ductile shear zones from time to time, but tend to be obliterated by continued shearing. Resistance to shear within the fault zone reaches a peak value (greatest for thrusts and least for normal faults) around the EF/QP transition level, which for normal geothermal gradients and an adequate supply of water, occurs at depths of 10–15 km.",
    url = "https://doi.org/10.1144/gsjgs.133.3.0191",
    doi = "10.1144/gsjgs.133.3.0191",
    openalex = "W2155128667",
    references = "doi1010160040195164900101, doi101098rsta19760079, doi101111j1365246x1967tb06218x, doi101144transed83387, doi105408002213687121"
}

@article{doi101029jb085ib10p05389,
    author = "Bergman, Eric and Solomon, Sean C.",
    title = "Oceanic intraplate earthquakes: Implications for local and regional intraplate stress",
    year = "1980",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Focal mechanisms of intraplate earthquakes provide the only means at present by which to characterize the long‐wavelength tectonic stress field in oceanic lithosphere. Stress orientations inferred from focal mechanisms may not accurately reflect the state of stress in the epicentral area, however, or the measured stresses may be dominated by local rather than regional sources. To establish a data set with which to study these possibilities, a comprehensive catalog of 159 oceanic intraplate earthquakes has been compiled for events since 1963 with m b 4.7 or larger. Focal mechanisms are available for approximately one quarter of the events, and several new mechanisms are presented here. For a representative subset of this catalog (83 events), the bathymetry and tectonic history of the epicentral areas have been assembled, and the earthquakes have been rated according to their association with (1) a preexisting fault zone, which might decouple the P axis of the focal mechanism from the true orientation of maximum compressive stress, and (2) large bathymetric relief, which might be a source of large local stresses. Oceanic intraplate earthquakes are commonly found in association with zones of previous weakness (usually fracture zones), but they do not show any particular association with large bathymetric features. In the central Indian Ocean there are enough focal mechanisms available to establish a well‐defined NW‐SE orientation for P axes and presumably for the direction of greatest compressive stress. The consistency of the P axes of these widely varying mechanisms in the presence of the Ninetyeast Ridge, a site of major intraplate deformation and large bathymetric relief, is remarkable. A possible explanation is that in the presence of a large number of preexisting faults with a range of orientations, slip occurs on those faults which have large resolved shear stresses from the regional stress field. In such an instance the P axis of focal mechanisms will tend to show a consistent alignment with the true direction of maximum stress.",
    url = "https://doi.org/10.1029/jb085ib10p05389",
    doi = "10.1029/jb085ib10p05389",
    openalex = "W1999221527"
}

@article{doi101111j1365246x1982tb05994x,
    author = "McNutt, Marcia and Menard, H. W.",
    title = "Constraints on yield strength in the oceanic lithosphere derived from observations of flexure",
    year = "1982",
    journal = "Geophysical Journal International",
    abstract = "Summary. The wavelength and amplitude of outer rises seaward of sub-duction zones and arches surrounding islands and seamounts are used to parameterize flexure profiles in terms of the moment and curvature at the first zero crossing. The data show the clear age dependence in the mechanical thickness of the lithosphere up to 60–100Myr. Saturation of moment at large curvature is interpreted in terms of a depth-dependent yield strength for the lithosphere using relations adopted from laboratory experiments of rock deformation. A comparison of theoretical curves with observed moments indicates that old oceanic lithosphere has no long-term strength below about 40 km depth, with no difference between 100 and 165 Myr old crust. Moderate axial loading forces (±200 MPa) can explain most variations in the moment/curvature observations, except in the case of the Kuril Trench which appears anomalous given the age of the crust. Regional tension causes greater variability in moment as compared to regional compression because of the greater slope in the brittle failure envelope under tension. The observations point to a lithosphere weaker than the prediction from experimental deformation of rocks. Of the possible weakening mechanisms, elevated pore-fluid pressure on faults does not predict the correct age dependence and is incompatible with earthquake focal mechanisms. Our favoured explanation is that the activation energy, Q, appropriate for ductile flow at geological strain rates is lower than the values derived from laboratory extrapolations of dry olivine data taken at high temperatures. If recent oceanic geotherms are reliable, Q in the lower lithosphere must be lower than 100kcal mol−1. The method used here is most appropriate for trench profiles with curvatures greater than 10−7m−1. For lower curvatures, such as along seamount profiles, small errors in the curvature estimate cause large changes in rheological parameters.",
    url = "https://doi.org/10.1111/j.1365-246x.1982.tb05994.x",
    doi = "10.1111/j.1365-246x.1982.tb05994.x",
    openalex = "W1974405388"
}

@article{doi101785bssa0720010151,
    author = "Sibson, Richard H.",
    title = "Fault zone models, heat flow, and the depth distribution of earthquakes in the continental crust of the United States",
    year = "1982",
    journal = "Bulletin of the Seismological Society of America",
    abstract = "abstract Models of fault zones in continental crust, based on the analysis of rock deformation textures, suggest that the depth of seismic activity is controlled by the passage from a pressure-sensitive, dominantly frictional regime to strongly temperature-dependent, quasi-plastic mylonitization at greenschist and higher grades of metamorphism. Sufficient knowledge now exists concerning the frictional and rheological properties of quartz-bearing rocks to construct crude strength-depth curves for different geotherms. In such models, shear resistance peaks sharply at the inferred seismic-aseismic transition. The maximum depth of microseismic activity in various heat flow provinces of the conterminous United States generally correlates well with the frictional to quasi-plastic transition modeled for the different geotherms. Larger earthquakes (M L > 5.5) also tend to nucleate near the base of the seismogenic zone. This region is postulated to have the highest concentration of distortional strain energy for stress levels at failure, and can be regarded as the prime asperity in crustal fault zones.",
    url = "https://doi.org/10.1785/bssa0720010151",
    doi = "10.1785/bssa0720010151",
    openalex = "W2309907070"
}

@article{doi101029jb089ib07p05681,
    author = "Schwartz, David P. and Coppersmith, Kevin J.",
    title = "Fault behavior and characteristic earthquakes: Examples from the Wasatch and San Andreas Fault Zones",
    year = "1984",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Paleoseismological data for the Wasatch and San Andreas fault zones have led to the formulation of the characteristic earthquake model, which postulates that individual faults and fault segments tend to generate essentially same size or characteristic earthquakes having a relatively narrow range of magnitudes near the maximum. Analysis of scarp‐derived colluvium in trench exposures across the Wasatch fault provides estimates of the timing and displacement associated with individual surface faulting earthquakes. At all of the sites studied, the displacement per event has been consistently large; measured values range from 1.6 to 2.6 m, and the average is about 2 m. On the basis of variability in the timing of individual events as well as changes in scarp morphology and fault geometry, six major segments are recognized along the Wasatch fault. On the basis of the most likely number of surface faulting events (18) that have occurred on segments of the Wasatch fault zone during the past 8000 years, an average recurrence interval of 400–666 years with a preferred average of 444 years is calculated for the entire zone. Geologic data on the distribution of slip associated with prehistoric earthquakes and slip rates along the south‐central segment of the San Andreas fault suggest that the M 8 1857 earthquake is a characteristic earthquake for this segment. Comparisons of earthquake recurrence relationships on both the Wasatch and San Andreas faults based on historical seismicity data and geologic data show that a linear (constant b value) extrapolation of the cumulative recurrence curve from the smaller magnitudes leads to gross underestimates of the frequency of occurrence of the large or characteristic earthquakes. Only by assuming a low b value in the moderate magnitude range can the seismicity data on small earthquakes be reconciled with geologic data on large earthquakes. The characteristic earthquake appears to be a fundamental aspect of the behavior of the Wasatch and San Andreas faults and may apply to many other faults as well.",
    url = "https://doi.org/10.1029/jb089ib07p05681",
    doi = "10.1029/jb089ib07p05681",
    openalex = "W2079238116"
}

@article{doi101029jb091ib01p00579,
    author = "Huang, Paul Y. and Solomon, Sean C. and Bergman, Eric and Nábělek, J.",
    title = "Focal depths and mechanism of Mid‐Atlantic Ridge earthquakes from body waveform inversion",
    year = "1986",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We have determined the source mechanisms (double‐couple orientation, moment, centroid depth, source time function) of 14 earthquakes on the northern Mid‐Atlantic Ridge (0°–72°N) from an inversion of long‐period P and SH waveforms. The earthquakes are all characterized by nearly pure normal faulting on fault planes that dip at about 45° and strike parallel to the local trend of the ridge axis. Moments range from 3 to 15×10 24 dyn cm, and the source time functions are all of simple form. The P and S waveforms for all earthquakes can be well matched using conventional values for t * (1 and 4 s, respectively). These earthquakes are all very shallow; centroid depths range between 1.2 and 3.1 km beneath the seafloor. The P waves from these earthquakes show strong water column reverberations, suggesting that fault rupture extended to the seafloor. The predominant period of these reverberations constrains the water depth in the epicentral region. On the basis of estimated water depth and epicentral location, all of these earthquakes can be shown to have occurred beneath the inner floor of the median valley. The centroid depths do not show a correlation with either spreading rate or seismic moment. Under the assumption that the centroid depth marks the mean depth of fault slip, earthquake faulting extended to depths of 2–6 km for these events.",
    url = "https://doi.org/10.1029/jb091ib01p00579",
    doi = "10.1029/jb091ib01p00579",
    openalex = "W2070406202",
    references = "doi1010160040195181901311, doi101029jb073i018p05855, doi101029jb083ib11p05331, doi101029jb084ib11p06140, doi101029jb091ib14p13993, doi101029jz067i013p05279, doi101029me004p0001, doi101111j1365246x1958tb00033x, doi10150830000033586, doi101785bssa0650051073, openalexw1579868249, sykes1967mechanism"
}

@article{doi101029jb091ib14p13993,
    author = "Jemsek, John P. and Bergman, Eric and Nábělek, J. and Solomon, Sean C.",
    title = "Focal depths and mechanisms of large earthquakes on the Arctic Mid‐Ocean Ridge System",
    year = "1986",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "As part of a global study of the source characteristics and tectonic implications of large earthquakes on mid‐ocean ridges, we report on the focal depths and mechanisms of the six largest earthquakes that have occurred in the last 20 years on the Arctic mid‐ocean ridge system. For each earthquake we invert the long‐period P and SH waveforms to estimate the parameters of the best fitting point source, including seismic moment, centroid depth, double‐couple source orientation, and source time function. Three of the earthquakes occurred on the oceanic spreading center in the Eurasian Basin, along ridge segments spreading at half rates of 4–6 mm/yr. These events have mechanisms very similar to those of ridge crest earthquakes on the Mid‐Atlantic Ridge: almost pure normal faulting on planes that dip at approximately 45° and strike parallel to the rift axis, moments of 4–5 × 10 24 dyn cm, centroid depths of 1–2 km beneath the seafloor, and water depths (inferred from the predominant period of water column reverberations) appropriate to epicentral locations within the median valley. The remaining three earthquakes, also characterized by normal faulting, are associated with the continuation of the divergent plate boundary (2–3 mm/yr half rate) onto the continental shelf of the Laptev Sea, where the crust becomes transitional in nature. One of the largest known spreading center earthquakes (August 25, 1964, M 0 = 1 × 10 26 dyn cm) occurred where the oceanic ridge intersects the outer edge of the continental slope. Waveform inversion for this event can resolve unilateral rupture from north to south (landward) along a fault at least 30 km in length. The preferred centroid depth is 5 km beneath the seafloor in crustal material with an unusually low shear velocity, but a centroid depth as great as 15 km cannot be ruled out. Two earthquakes beneath the continental shelf have significantly greater centroid depths (10–20 km) than mid‐ocean ridge earthquakes, indicating a thicker brittle regime and a cooler thermal structure than are typical of oceanic spreading centers. The tectonic environment of these events is more representative of rifted continental lithosphere than of a mid‐ocean ridge.",
    url = "https://doi.org/10.1029/jb091ib14p13993",
    doi = "10.1029/jb091ib14p13993",
    openalex = "W1975000436",
    references = "doi101007bf00300398, doi1010160012821x78900717, doi101029jb073i018p05855, doi101029jb083ib11p05331, doi101029jb084ib03p01071, doi101029jb088ib05p04183, doi101029jb090ib08p06709, doi10113000167606197283619ssitna20co2, openalexw1579868249, sykes1967mechanism"
}

@article{doi101029jb093ib08p09027,
    author = "Bergman, Eric and Solomon, Sean C.",
    title = "Transform fault earthquakes in the North Atlantic: Source mechanisms and depth of faulting",
    year = "1988",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We have determined the centroid depths and source mechanisms of 12 large earthquakes on transform faults of the northern Mid‐Atlantic Ridge from an inversion of long‐period body waveforms. The earthquakes occurred on the Gibbs, Oceanographer, Hayes, Kane, 15°20′, and Vema transforms. We have also estimated the depth extent of faulting during each earthquake from the centroid depth and the fault width. For five of the transforms, earthquake centroid depths lie in the range 7–10 km beneath the seafloor, and the maximum depth of seismic faulting is 14–20 km. On the basis of a comparison with a simple thermal model for transform faults, this maximum depth of seismic behavior corresponds to a nominal temperature of 900° ± 100°C. In contrast, the nominal temperature limiting the maximum depth of faulting during oceanic intraplate earthquakes with strike‐slip mechanisms is 700° ± 100°C. The difference in these limiting temperatures may be attributed to the different strain rates characterizing intraplate and transform fault environments. Three large earthquakes on the 15°20′ transform have shallower centroid depths of 4–5 km and a maximum depth of seismic faulting of 10 km, corresponding to a limiting temperature of 600°C. The shallower extent of seismic behavior along the 15°20′ transform may be related to a recent episode of extension across the transform associated with the northward migration of the triple junction among North American, South American, and African plates to its present position near the transform. The source mechanisms for all events in this study display the strike‐slip motion expected for transform fault earthquakes; slip vector azimuths agree to within 2°–3° of the local strike of the zone of active faulting. The only anomalies in mechanism were for two earthquakes near the western end of the Vema transform which occurred on significantly nonvertical fault planes. Secondary faulting, occurring either precursory to or near the end of the main episode of strike‐slip rupture, was observed for five of the 12 earthquakes. For three events the secondary faulting was characterized by reverse motion on fault planes striking oblique to the trend of the transform. In all three cases the site of secondary reverse faulting is near a compressional jog in the current trace of the active transform fault zone. We find no evidence to support the conclusions of Engeln, Wiens, and Stein that oceanic transform faults in general are either hotter than expected from simple thermal models or weaker than normal oceanic lithosphere.",
    url = "https://doi.org/10.1029/jb093ib08p09027",
    doi = "10.1029/jb093ib08p09027",
    openalex = "W2163562760",
    references = "doi1010160031920181900467, doi101029jb082i005p00803, doi101029jb083ib11p05331, doi101029jb085ib11p06248, doi101029jb088ib05p04183, doi101029jb091ib01p00579, doi101029jb091ib14p13993, doi101111j1365246x1979tb02567x, doi101130dnaggnam351, doi101785bssa0650051073, doi101785bssa0720010151, openalexw1579868249"
}

@article{doi101029jb094ib05p05585,
    author = "Argus, Donald F. and Gordon, Richard G. and DeMets, Charles and Stein, Seth",
    title = "Closure of the Africa‐Eurasia‐North America Plate motion circuit and tectonics of the Gloria Fault",
    year = "1989",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We examine the closure of the current plate motion circuit between the African, North American, and Eurasian plates to test whether these plates are rigid and whether the Gloria fault is an active transform fault. We also investigate the possible existence of microplates that have been previously proposed to lie along these plate boundaries, and compare the predicted direction of motion along the African‐Eurasian plate boundary in the Mediterranean with the direction of slip observed in earthquakes. From marine geophysical data we obtain 13 transform fault azimuths and 40 3‐m.y.‐average spreading rates, 34 of which are determined from comparison of synthetic magnetic anomaly profiles to ∼140 observed profiles. Slip vectors from 32 earthquake focal mechanisms further describe plate motion. Detailed magnetic surveys north of Iceland provide 11 rates in a region where prior plate motion models had few data. Magnetic profiles north of the Azores triple junction record a rate of 24 mm/yr, 4 mm/yr slower than used by prior models. Gloria and Sea Beam surveys accurately measure the azimuths of seven transform faults; our plate motion model fits six of the seven within 2°. Two transform faults surveyed by Gloria side scan sonar lie near FAMOUS area transform faults A and B and give azimuths 13° clockwise of them. Because recent studies show that short‐offset transforms, such as transforms A and B, are in many places oblique to the direction of plate motion, we exclude azimuths from transforms with less than 35‐km offset. The best fitting and closure‐enforced vectors fit the data well, except for a small systematic misfit to the slip vectors: On right‐lateral slipping transforms, slip vectors tend to be a few degrees clockwise of plate motion and mapped fault azimuths, whereas on left‐lateral slipping transforms, slip vectors tend to be a few degrees counterclockwise of plate motion and mapped fault azimuths. We search the long Eurasia‐North America boundary for evidence of an additional plate, but find no systematic misfits to the data. In particular, if a Spitsbergen plate exists and moves relative to Eurasia, its motion is less than 3 mm/yr. An Africa‐Eurasia Euler vector determined by adding the Eurasia‐North America and Africa‐North America Euler vectors is consistent with the Gloria fault trend and with slip vectors from eastern Azores‐Gibraltar Ridge focal mechanisms. A small circle, centered at the Africa‐Eurasia closure‐enforced pole, fits the trace of the Gloria fault. The model in which closure was enforced predicts ∼4 mm/yr slip across the Azores‐Gibraltar Ridge, and west‐northwest convergence near Gibraltar, ∼45° more oblique than suggested by a recent model based on compressive axes of focal mechanisms. Moreover, our model predicts directions of plate motion that agree well with northwest trending slip vectors from thrust earthquakes between Gibraltar and Sicily. Because closure‐enforced vectors fit the data nearly as well as the best fitting vectors, we conclude that the data are consistent with a rigid plate model and with the Gloria fault being a transform fault.",
    url = "https://doi.org/10.1029/jb094ib05p05585",
    doi = "10.1029/jb094ib05p05585",
    openalex = "W2025021642",
    references = "doi1010160040195181901311, doi101029jb084ib03p01071, doi101029jb093ib08p09027"
}

@article{doi105860choice281579,
    author = "Scholz, C. H., (Christopher H.)",
    title = "The mechanics of earthquakes and faulting",
    year = "1990",
    journal = "Choice Reviews Online",
    abstract = "The third edition of this classic treatise presents a wealth of new topics and new observations. These include slow earthquake phenomena; friction of phyllosilicates, and at high sliding velocities; fault structures; relative roles of strong and seismogenic versus weak and creeping faults; dynamic triggering of earthquakes; oceanic earthquakes; megathrust earthquakes in subduction zones; deep earthquakes; and new observations of earthquake precursory phenomena.",
    url = "https://doi.org/10.5860/choice.28-1579",
    doi = "10.5860/choice.28-1579",
    openalex = "W2110448165",
    references = "doi101007bf00876528, doi1010160022509660900132, doi1010160040195183901488, doi1010160191814184900014, doi1010160191814188900570, doi101016s0065215608701212, doi10102992jb00132, doi101029jb073i018p05855, doi101029jb075i014p02625, doi101029jb075i026p04997, doi101029jb076i026p06414, doi101029jb082i020p02981, doi101029jb083ib11p05331, doi101029jb085ib11p06248, doi101029jb088ib02p01153, doi101029jb088ib05p04183, doi101029jb089ib06p04344, doi101029jb091ib12p12587, doi101029jb092ib06p04798, doi101029jb093ib08p09027, doi101029jz070i016p03965, doi101029jz072i008p02131, doi101029me001, doi101029rg009i001p00103, doi101029rg016i004p00621, doi101029rg018i001p00269, doi101029tc007i003p00663, doi101038207343a0, doi101038284135a0, doi101038334058a0, doi10106311721448, doi101098rspa19570133, doi101098rspa19660242, doi101098rsta19210006, doi101103physreva38364, doi101103physrevlett59381, doi101111j1365246x1975tb00631x, doi101111j1365246x1990tb06579x, doi10111513601206, doi101126science19142331230, doi101130001676061977881667dawtmo20co2, doi101144transed83387, doi101785bssa0350040175, sykes1967mechanism"
}

@article{doi10102993jb00349,
    author = "Pacheco, Javier F. and Sykes, Lynn R. and Scholz, Christopher H.",
    title = "Nature of seismic coupling along simple plate boundaries of the subduction type",
    year = "1993",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "The downdip width of the seismogenic zone is defined for 19 subduction zones. This width is measured from the base of the accretionary prism to the maximum depth of nucleation of thrust events along the plate boundary. Those two points are taken to define the upper and lower depth transitions from stable to unstable frictional sliding. The lower depth transition is found to be between 35 and 70 km. The dip angle of the thrust zone is also reevaluated. We find a linear increase in the dip angle as a function of depth, the slope of which varies between 0.2° and 0.6° km −1. The downdip width obtained, which is generally narrower than previously determined by most other authors, varies from about 50 to 150 km. We also determine the ratio of the rate of slip that occurs in earthquakes to the rate of relative plate motion. This ratio is defined as the seismic coupling coefficient (a). We obtain two different estimates of the seismic coupling coefficient: an average value from 90 years of seismicity and a value obtained using the slip‐predictable recurrence model for large earthquakes. We find a large variation in the computed values of a along and among subduction zones. For most of the subduction zones a is much less than 1.0; for several it is less than a few percent. Worldwide, we find no significant correlation between either the seismic coupling coefficient or the width of the seismogenic zone and subduction parameters such as the age of the oceanic lithosphere that is being subducted, plate convergence rates or absolute velocity of the upper plate in the hot spot reference frame. Such correlation exists only for a few individual subduction zones where other parameters do not vary as much. The observed variations in seismic coupling could be explained as differences in the frictional behavior of materials at the plate interface. Some of these differences may be attributed to the subduction of large bathymetric features, the roughness of topography, the presence of unstable triple junctions and active‐spreading ridges, and sediment composition.",
    url = "https://doi.org/10.1029/93jb00349",
    doi = "10.1029/93jb00349",
    openalex = "W2151513949",
    references = "doi101029jb094ib06p07293"
}

@article{doi10102994jb02593,
    author = "Thatcher, Wayne and Hill, David P.",
    title = "A simple model for the fault‐generated morphology of slow‐spreading mid‐oceanic ridges",
    year = "1995",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We postulate that fluctuations in magmatic activity at mid‐oceanic ridges perturb the horizontal least principal stress across rift‐bounding normal faults, leading to alternating phases of magmatic accretion, which increases valley width, and tectonic extension, which results in the growth of inner rift wall topography. Fine‐scale bathymetrie surveys and earthquake fault plane solutions show that active normal faults at slow‐spreading ridges are moderately dipping (approximately 45°) planar features throughout the seismogenic oceanic lithosphere. A simple quantitative model that includes flexural deformation of a 10‐km‐thick elastic plate by slippage on 45° dipping normal faults can match the bathymetrie profiles across several slow‐spreading ridge segments. Comparison among dip distributions of normal‐faulting earthquakes at mid‐ocean ridges, in the trench‐outer rise region, and on continents suggests that most events from these three tectonic environments initiated at dips close to 45°, raising unanswered questions about the mechanical conditions under which the faults originated.",
    url = "https://doi.org/10.1029/94jb02593",
    doi = "10.1029/94jb02593",
    openalex = "W2100163176",
    references = "doi101007bf00369150, doi101007bf01204232, doi1010160148906289919852, doi1010160191814189900333, doi101017cbo9780511735349, doi10102993jb01565, doi101029jb091ib14p13993, doi101029jb093ib11p13421, doi101029tc007i005p00959, doi101111j1365246x1989tb02020x, doi101111j1365246x1991tb03906x"
}

@book{doi10157519125693,
    author = "Jaroslow, Gary E.",
    title = "The geological record of oceanic crustal accretion and tectonism at slow-spreading ridges",
    year = "1996",
    abstract = "The objective of this Thesis was to interpret the structural development of slowspreading ridge segments by: 1) delineating the nature, magnitude, and relative importance of primary tectonic and volcanic processes that control crustal morphology, 2) investigating the spatial and temporal variability of these processes, and 3) examining how rheological variations in the lithosphere control its structural configuration. To that end, this Thesis provides detailed documentation of faults and volcanoes (seamounts) at the Mid-Atlantic Ridge from 2525'N to 2710'N and extending from zero-age crust at the ridge axis to -29 Ma crust on the ridge flank. This information was used to analyze the evolution of ocean crust from initial formation in the rift valley to degradation by aging processes on the ridge flank. Accumulation of sediments affects the seafloor morphological expression of ocean crustal structure, and sediment thicknesses were also mapped to facilitate study of the morphological record of crustal accretion and tectonism. In addition, deformation conditions in the lithosphere were analyzed by study of microstructure and geothermometry of abyssal peridotite mylonites recovered from fault zones at slow-spreading ridges.",
    url = "https://doi.org/10.1575/1912/5693",
    doi = "10.1575/1912/5693",
    openalex = "W1482970135",
    references = "doi1010029781118782149ch1, doi1010160040195187903489, doi101016019181419290053y, doi101029jb082i005p00803, doi101029jb085ib11p06248, doi101029jb088ib05p04183, doi101038326035a0, doi101086627339, doi101126science2605109771, doi101130001676061970812181htfoda20co2, doi101144gslsp19890420106, sykes1972mechanism"
}

@article{doi101126science28053671245,
    author = "Pollitz, Fred F. and Bürgmann, Roland and Romanowicz, Barbara",
    title = "Viscosity of Oceanic Asthenosphere Inferred from Remote Triggering of Earthquakes",
    year = "1998",
    journal = "Science",
    abstract = "A sequence of large interplate earthquakes from 1952 to 1965 along the Aleutian arc and Kurile-Kamchatka trench released accumulated stresses along nearly the entire northern portion of the Pacific Plate boundary. The postseismic stress evolution across the northern Pacific and Arctic basins, calculated from a viscoelastic coupling model with an asthenospheric viscosity of 5 x 10(17) pascal seconds, is consistent with triggering of oceanic intraplate earthquakes, temporal patterns in seismicity at remote plate boundaries, and space-based geodetic measurements of anomalous velocity over an area 7000 by 7000 kilometers square during the 30-year period after the sequence.",
    url = "https://doi.org/10.1126/science.280.5367.1245",
    doi = "10.1126/science.280.5367.1245",
    openalex = "W1979854288",
    references = "doi101007bf00875969, doi10102994gl02118, doi10102994jb01405, doi10102997jb00514, doi10102997jb01277, doi101029jb084ib05p02348, doi101029jb085ib10p05389, doi101029jb091ib14p13993, doi101038359123a0, doi101111j1365246x1982tb05994x, doi101785bssa0840030935"
}

@article{doi101046j1365246x200201720x,
    author = "Choy, George L. and McGarr, A.",
    title = "Strike-slip earthquakes in the oceanic lithosphere: observations of exceptionally high apparent stress",
    year = "2002",
    journal = "Geophysical Journal International",
    abstract = "The radiated energies, ES, and seismic moments, M0, for 942 globally distributed earthquakes that occurred between 1987 to 1998 are examined to find the earthquakes with the highest apparent stresses (τa=μES/M0, where μ is the modulus of rigidity). The globally averaged τa for shallow earthquakes in all tectonic environments and seismic regions is 0.3 MPa. However, the subset of 49 earthquakes with the highest apparent stresses (τa greater than about 5.0 MPa) is dominated almost exclusively by strike-slip earthquakes that occur in oceanic environments. These earthquakes are all located in the depth range 7–29 km in the upper mantle of the young oceanic lithosphere. Many of these events occur near plate-boundary triple junctions where there appear to be high rates of intraplate deformation. Indeed, the small rapidly deforming Gorda Plate accounts for 10 of the 49 high-τa events. The depth distribution of τa, which shows peak values somewhat greater than 25 MPa in the depth range 20–25 km, suggests that upper bounds on this parameter are a result of the strength of the oceanic lithosphere. A recently proposed envelope for apparent stress, derived by taking 6 per cent of the strength inferred from laboratory experiments for young (less than 30 Ma) deforming oceanic lithosphere, agrees well with the upper-bound envelope of apparent stresses over the depth range 5–30 km. The corresponding depth-dependent shear strength for young oceanic lithosphere attains a peak value of about 575 MPa at a depth of 21 km and then diminishes rapidly as the depth increases. In addition to their high apparent stresses, which suggest that the strength of the young oceanic lithosphere is highest in the depth range 10–30 km, our set of high-τa earthquakes show other features that constrain the nature of the forces that cause interplate motion. First, our set of events is divided roughly equally between intraplate and transform faulting with similar depth distributions of τa for the two types. Secondly, many of the intraplate events have focal mechanisms with the T-axes that are normal to the nearest ridge crest or subduction zone and P-axes that are normal to the proximate transform fault. These observations suggest that forces associated with the reorganization of plate boundaries play an important role in causing high-τa earthquakes inside oceanic plates. Extant transform boundaries may be misaligned with current plate motion. To accommodate current plate motion, the pre-existing plate boundaries would have to be subjected to large horizontal transform push forces. A notable example of this is the triple junction near which the second large aftershock of the 1992 April Cape Mendocino, California, sequence occurred. Alternatively, subduction zone resistance may be enhanced by the collision of a buoyant lithosphere, a process that also markedly increases the horizontal stress. A notable example of this is the Aleutian Trench near which large events occurred in the Gulf of Alaska in late 1987 and the 1998 March Balleny Sea M= 8.2 earthquake within the Antarctic Plate.",
    url = "https://doi.org/10.1046/j.1365-246x.2002.01720.x",
    doi = "10.1046/j.1365-246x.2002.01720.x",
    openalex = "W2132379360",
    references = "doi101007bf00876528, doi10102995jb01460, doi101029jb076i011p02542, doi101029jb077i023p04432, doi101029jb085ib11p06248, doi101029jb086ib04p02825, doi101111j1365246x1975tb00631x, doi101111j1365246x1979tb02567x, doi101111j1365246x1990tb06579x, doi101111j1365246x1991tb06724x"
}

@article{doi1010292001jb000814,
    author = "Abercrombie, Rachel E. and Ekström, Göran",
    title = "A reassessment of the rupture characteristics of oceanic transform earthquakes",
    year = "2003",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "We investigate the long‐period source spectra of oceanic transform earthquakes and find that previously proposed slow rupture components can be explained as artifacts generated by the modeling procedure. We use low‐frequency (≤20 mHz) Rayleigh and Love waves to calculate the amplitude spectra of five earthquakes on the Romanche and Chain transform faults in the equatorial mid‐Atlantic Ocean. We find that errors and approximations in the centroid depth, focal mechanism, and earth structure at the source have significant effects on the shape of the source spectra. If global catalog values and an average crustal model are assumed, the spectra exhibit apparent anomalous energy at long periods which has previously been interpreted as a result of slow rupture. We recalculate the source spectra using precise, independently determined depths and moment tensors and a more realistic oceanic crustal structure in the source region. The resulting source spectra are flat at long periods with no indication of anomalous long‐period energy. Our results imply that oceanic transform earthquakes do not commonly have detectable slow rupture components.",
    url = "https://doi.org/10.1029/2001jb000814",
    doi = "10.1029/2001jb000814",
    openalex = "W2060276802",
    references = "doi101046j1365246x200201720x"
}

@article{doi1010292005jb003785,
    author = "Antolik, Michael and Abercrombie, Rachel E. and Pan, Jianfeng and Ekström, Göran",
    title = "Rupture characteristics of the 2003 M w 7.6 mid‐Indian Ocean earthquake: Implications for seismic properties of young oceanic lithosphere",
    year = "2006",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "Analysis of broadband seismograms from the 15 July 2003 large earthquake (M 7.6) in the central Indian Ocean reveals an unusual source process. The source duration of longer than a minute is more than twice as long as expected from earthquake scaling relations, yet ∼80\% of the moment release occurred in two energetic asperities near the end of the rupture. These two asperities were located in lithosphere with an age of 7 Ma or greater. A previous study has suggested that strike‐slip earthquakes in oceanic lithosphere having much longer than expected source durations also have a slow, dissipative rupture process characterized by low radiated seismic energy (and therefore low apparent stress). We find no evidence for a slow rupture process to the 2003 earthquake. Instead, the long duration appears to be due only to nucleation close to the actively spreading Carlsberg Ridge, in lithosphere younger than 7 Ma. Younger oceanic lithosphere may be able to generate small to moderate earthquakes but be unable to sustain slip in a large event due to steady release of strain in aseismic creep events. Large strike‐slip earthquakes within oceanic lithosphere may occur only in the central portions of long transform faults or in intraplate regions, rupturing energetic asperities like those that failed in the mid‐Indian Ocean earthquake and leading to the observation that oceanic strike‐slip earthquakes have the largest apparent stresses among the global population of shallow earthquakes.",
    url = "https://doi.org/10.1029/2005jb003785",
    doi = "10.1029/2005jb003785",
    openalex = "W2060977265",
    references = "doi101046j1365246x200201720x"
}

@article{doi1010292007jb005213,
    author = "Braunmiller, Jochen and Nábělek, J.",
    title = "Segmentation of the Blanco Transform Fault Zone from earthquake analysis: Complex tectonics of an oceanic transform fault",
    year = "2008",
    journal = "Journal of Geophysical Research Atmospheres",
    abstract = "The Blanco Transform Fault Zone (BTFZ) forms the ∼350 km long Pacific–Juan de Fuca plate boundary between the Gorda and Juan de Fuca ridges. Nearby broadband seismic networks provide a unique framework for a detailed, long‐term seismotectonic study of an entire oceanic transform fault (OTF) system. We use regional waveforms to determine 129 earthquake source parameters; combined with 28 Harvard moment tensors, they represent the largest waveform derived OTF source parameter data set. Joint epicenter determination removes the northeasterly routine location bias. Projecting seismicity onto the BTFZ, we determine along‐fault seismic slip rate variations. Earthquake source parameters and morphology indicate several transform segments separated by extensional step overs. The eastern segment from Gorda Ridge to Gorda Depression is a pull‐apart basin. The longest transform (∼150 km) following Blanco Ridge from the Gorda to Cascadia depression is seismically very active, seismically fully coupled, has a wider seismic zone (∼9 km) than other BTFZ transform segments and accommodates the largest (M w 6.4–6.5) BTFZ earthquakes. Interpretation of Cascadia Depression as spreading ridge is supported by plate motion parallel normal faulting T axes. Spreading is currently tectonic; 9 km deep earthquakes indicate a deep source for intermittent intrusives and rapid postemplacement cooling. A short transform connects to the pull‐apart Surveyor Depression. Widely spread seismicity along the western BTFZ reflects complex morphology indicating ongoing plate boundary reorganization along short, narrow width subparallel faults. Seismic coupling is low in extensional (≤15\%) compared to transform areas (35–100\%), implying different mechanical properties. Centroid depth variations are consistent with seismic slip cutoff near 600°C.",
    url = "https://doi.org/10.1029/2007jb005213",
    doi = "10.1029/2007jb005213",
    openalex = "W2170344966",
    references = "doi1010160012825281900441, doi101017cbo9780511807442, doi101017cbo9780511818516, doi10102995eo00198, doi101029jb073i002p00777, doi101029jb084ib05p02348, doi101029jb091ib14p13993, doi101111j1365246x1969tb00259x, doi105860choice281579, openalexw1579868249, openalexw3041301201"
}

@article{doi101038nature07333,
    author = "Escartı́n, J. and Smith, Deborah K. and Cann, J. and Schouten, Hans and Langmuir, C. H. and Escrig, Stéphane",
    title = "Central role of detachment faults in accretion of slow-spreading oceanic lithosphere",
    year = "2008",
    journal = "Nature",
    url = "https://doi.org/10.1038/nature07333",
    doi = "10.1038/nature07333",
    openalex = "W1986522418",
    references = "doi1010291999gc000026, doi10102996jb01781, doi10102998jb00167, doi101038321033a0, doi10103835084000, doi101038385329a0, doi101038nature03358, doi101130g224861, doi101130g23718a1, doi101130g24639a1"
}

@incollection{doi101029148gm03,
    author = "Searle, R. C. and Escartı́n, J.",
    title = "The Rheology and Morphology of Oceanic Lithosphere and Mid-Ocean Ridges",
    year = "2011",
    booktitle = "Geophysical monograph",
    abstract = "This chapter contains sections titled: Introduction Rheology of the Oceanic Lithosphere The Thermal Structure of Oceanic Lithosphere Flexure and the Elastic Properties of the Lithosphere The Thickness of the Seismogenic Zone The Median Valley and the Axial High Morphology and Crustal Architecture of Ridge Segments Lithological Structure of Mid-Ocean Ridges Faulting at Mid-Ocean Ridges Summary of Observations: Rheological Structure of Slow and Fast-Spreading Ridges Conclusions",
    url = "https://doi.org/10.1029/148gm03",
    doi = "10.1029/148gm03",
    openalex = "W1554533974",
    references = "doi10157519125693"
}

@article{doi101038nature09838,
    author = "Toro, Giulio Di and Han, Raehee and Hirose, Takehiro and Paola, N. De and Nielsen, S. B. and Mizoguchi, Kazuo and Ferri, F. and Cocco, M. and Shimamoto, Toshihiko",
    title = "Fault lubrication during earthquakes",
    year = "2011",
    journal = "Nature",
    url = "https://doi.org/10.1038/nature09838",
    doi = "10.1038/nature09838",
    openalex = "W2076670652",
    references = "doi105860choice281579"
}

@article{doi101111j1365246x201105092x,
    author = "Robinson, David P.",
    title = "A rare great earthquake on an oceanic fossil fracture zone",
    year = "2011",
    journal = "Geophysical Journal International",
    abstract = "Broad-band body and mantle wave data are used to study the 2004 December 23, Tasman Sea earthquake. In common with other strike-slip earthquakes studied in the same fashion, the mantle wave data indicates that there are two pure-double couple constrained solutions, along with a range of mechanisms between them, that fit the data almost equally well. Aftershocks relocated for this study indicate that the rupture occurred on a fracture zone which bends sharply in the epicentral region. Horizontally polarised S body waves and P body waves are used to determine the rupture parameters. A model with two faults best fits the data. The northern fault plane, with strike 160, dip 86 and rake 5, is compatible with the first motion solution found in this study and has a strike consistent with the fracture zone north of the bend. The southern fault plane, with strike 178, dip 54 and rake 65, has a strike consistent with the portion of the fracture zone to the south of the bend and has a dip which can be explained by the style of deformation that the region is undergoing. The centroid moment tensor solution of the broad-band model is calculated and found to be consistent with the region of low misfit in mantle wave solution space. The broad-band solution has a moment of 1.53 10 21 N m (M w 8.1), again, consistent with the mantle wave data. Slip propagated bilaterally with an approximate rupture velocity of 3 km s -1 80 per cent of local shear wave speed. The rupture front is less well resolved to the south of the epicentre than to the north. The majority (75 per cent) of moment originated from slip on the northern fault. The broad-band data requires significant slip below the oceanic Moho with as much as 70 per cent of moment due to slip in the brittle uppermost mantle in the preferred model.",
    url = "https://doi.org/10.1111/j.1365-246x.2011.05092.x",
    doi = "10.1111/j.1365-246x.2011.05092.x",
    openalex = "W2168633688",
    references = "doi101046j1365246x200201720x"
}

@article{doi101130b307541,
    author = "Whitney, Donna L. and Teyssier, Christian and Rey, Patrice and Buck, W. Roger",
    title = "Continental and oceanic core complexes",
    year = "2012",
    journal = "Geological Society of America Bulletin",
    abstract = "Core-complex formation driven by lithospheric extension is a first-order process of heat and mass transfer in the Earth. Core-complex structures have been recognized in the continents, at slow- and ultraslow-spreading mid-ocean ridges, and at continental rifted margins; in each of these settings, extension has driven the exhumation of deep crust and/or upper mantle. The style of extension and the magnitude of core-complex exhumation are determined fundamentally by rheology: (1) Coupling between brittle and ductile layers regulates fault patterns in the brittle layer; and (2) viscosity of the flowing layer is controlled dominantly by the synextension geotherm and the presence or absence of melt. The pressure-temperature-time-fluid-deformation history of core complexes, investigated via field- and modeling-based studies, reveals the magnitude, rate, and mechanisms of advection of heat and material from deep to shallow levels, as well as the consequences for the chemical and physical evolution of the lithosphere, including the role of core-complex development in crustal differentiation, global element cycles, and ore formation. In this review, we provide a survey of ∼40 yr of core-complex literature, discuss processes and questions relevant to the formation and evolution of core complexes in continental and oceanic settings, highlight the significance of core complexes for lithosphere dynamics, and propose a few possible directions for future research.",
    url = "https://doi.org/10.1130/b30754.1",
    doi = "10.1130/b30754.1",
    openalex = "W2071527329",
    references = "doi101007bf00300398, doi10102992jb02221, doi101038nature03358, doi101038nature07333, doi101130spe233p1"
}

@article{doi101002jgrb50267,
    author = "Wei, Shengji and Helmberger, D. V. and Avouac, Jean‐Philippe",
    title = "Modeling the 2012 Wharton basin earthquakes off‐Sumatra: Complete lithospheric failure",
    year = "2013",
    journal = "Journal of Geophysical Research Solid Earth",
    abstract = "Abstract A sequence of large strike‐slip earthquakes occurred west of Sunda Trench beneath the Wharton Basin. First reports indicate that the main shock was extremely complex, involving three to four subevents (M w > 8) with a maze of aftershocks. We investigate slip models of the two largest earthquakes by joint inversion of regional and teleseismic waveform data. Using the M w 7.2 foreshock, we developed hybrid Green's Functions for the regional stations to approximate the mixture of oceanic and continental paths. The main shock fault geometry is defined based on the back projection results, point‐source mechanisms, aftershock distribution, and fine tune of grid searches. The fault system contains three faults, labeled F1 (89°/289° for dip/strike), F2 (74°/20°), and F3 (60°/310°). The inversion indicates that the main rupture consisted of a cascade of high‐stress drop asperities (up to 30 MPa), extending as deep as 50 km. The rupture propagated smoothly from one fault to the next (F1, F2, and F3 in sequence) with rupture velocities of 2.0–2.5 km/s. The whole process lasted about 200 s, and the major moment release (>70\%) took place on the N‐S oriented F2. The M w 8.2 aftershock happened about 2 h later on a N‐S oriented fault with a relatively short duration (\textasciitilde 60 s) and also ruptured as deep as 50 km. The slip distributions suggest that the earthquake sequence was part of a broad left‐lateral shear zone between the Australian and Indian plates and ruptured the whole lithosphere. These earthquakes apparently reactivated existing fracture zones and were probably triggered by unclamping of the great Sumatran earthquake of 2004.",
    url = "https://doi.org/10.1002/jgrb.50267",
    doi = "10.1002/jgrb.50267",
    openalex = "W2108095936",
    references = "doi101046j1365246x200201720x"
}

@book{doi1010179781316681473,
    author = "Scholz, Christopher H.",
    title = "The Mechanics of Earthquakes and Faulting",
    year = "2018",
    booktitle = "Cambridge University Press eBooks",
    abstract = "This essential reference for graduate students and researchers provides a unified treatment of earthquakes and faulting as two aspects of brittle tectonics at different timescales. The intimate connection between the two is manifested in their scaling laws and populations, which evolve from fracture growth and interactions between fractures. The connection between faults and the seismicity generated is governed by the rate and state dependent friction laws - producing distinctive seismic styles of faulting and a gamut of earthquake phenomena including aftershocks, afterslip, earthquake triggering, and slow slip events. The third edition of this classic treatise presents a wealth of new topics and new observations. These include slow earthquake phenomena; friction of phyllosilicates, and at high sliding velocities; fault structures; relative roles of strong and seismogenic versus weak and creeping faults; dynamic triggering of earthquakes; oceanic earthquakes; megathrust earthquakes in subduction zones; deep earthquakes; and new observations of earthquake precursory phenomena.",
    url = "https://doi.org/10.1017/9781316681473",
    doi = "10.1017/9781316681473",
    openalex = "W4211212742",
    references = "doi1010160040195183901488, doi1010160191814184900014, doi1010160191814188900570, doi101016s0012821x03004242, doi101016s019181410200161x, doi1010291998rg900002, doi1010292005jb004051, doi1010292007jb004930, doi1010292007jb005213, doi10102992jb00132, doi10102992jb00517, doi10102995jb00862, doi10102996jb01651, doi101029jb076i026p06414, doi101029jb082i020p02981, doi101029jb088ib02p01153, doi101029jb089ib06p04344, doi101029jb091ib12p12587, doi101029jb092ib06p04798, doi101029jb093ib08p09027, doi101029jz070i016p03965, doi101029me001, doi101029rg016i004p00621, doi101029tc007i003p00663, doi101038284135a0, doi101038334058a0, doi101038nature03358, doi101038nature07333, doi101046j1365246x200201720x, doi101126science19142331230, doi101130001676061977881667dawtmo20co2, doi101144transed83387, doi101785bssa0350040175, openalexw191472345"
}

@incollection{aydan2022faults,
    author = "Aydan, Ömer",
    title = "Faults and faulting mechanism of earthquakes",
    year = "2022",
    booktitle = "Earthquake Science and Engineering",
    url = "https://doi.org/10.1201/9781003164371-4",
    doi = "10.1201/9781003164371-4",
    openalex = "W4281400367",
    pages = "55-81"
}

@misc{demont2025modes,
    author = "Demont, Antoine and Cannat, Mathilde and Olive, Jean-Arthur",
    title = "Modes of detachment faulting at slow and ultraslow mid-oceanic ridges",
    year = "2025",
    abstract = {Large-offset detachment faults are commonly observed at slow-spreading mid-ocean ridges (MORs), typically in areas with a moderate to low magma supply (e.g., 13\&\#186;20'N on the Mid-Atlantic Ridge). Detachments are also found at nearly amagmatic sections of ultraslow MORs (e.g., 64\&\#186;E on the Southwest Indian Ridge), where the seismogenic lithosphere is unusually thick (> 15 km). There, detachments of opposing polarity form in sequence and cross-cut each other in a "flip-flop" regime. Prior studies have shown that marked strength contrasts, resulting from reduced cohesion and/or friction in fault zones, promote stable detachments. Here we present 2-D thermo-mechanical models based on geological observations to examine how strength contrasts between fault zones and the adjacent lithosphere impact the modes of faulting at an ultraslow and nearly amagmatic ridge axis.We model the brittle lithosphere as a Mohr-Coulomb elasto-plastic material, where cohesion and friction diminish with increasing plastic strain. We explore a broad range of cohesion and friction contrasts between deformed and intact material. We also consider the influence of a strong, viscous lower lithosphere on the brittle deformation of the upper lithosphere by comparing simulations that use a dry olivine flow law with models where the brittle lithosphere sharply transitions into a low-viscosity asthenosphere. Fluid circulation in the shallow axial lithosphere is also considered, parameterizing both the cooling and the mechanical effect of hydrothermal circulation.Our simulations produce three distinct regimes: (1) sequential development of horsts bound by two active antithetic faults, (2) formation of intersecting \&\#8220;flip-flopping\&\#8221; detachments, (3) runaway detachments. The latter case describes models in which a single detachment remains active. In nature, this endmember case is not observed, probably because it results in an excessive migration of the detachment toward its hanging wall. We show that these 3 regimes transition over a narrow range of cohesion and friction contrasts between deformed and intact material (the contrast in friction coefficient over which our simulations transition from regimes 1 to 3 is only 0.1- 0.2). Distributed footwall damage produces antithetic proto-faults, but their ability to mature as major seafloor-breaching faults depends on the degree of rheological weakening. A stronger lower lithosphere promotes such distributed faulting and modifies the onset of the persistent detachment regime to greater strength contrasts. The impact of hydrostatic fluid pressure on tectonic styles is relatively minor compared to fault weakening.The results of these simulations are consistent with an analytical force balance model that compares the (localizing) loss of fault strength in the detachments to the (delocalizing) flexural force that develops in the surrounding lithosphere. Detachments persist when the magnitude of fault strength loss exceeds the maximum bending force. We find that runaway detachments require a total loss of integrated strength in excess of 1.5e12 N.m, equivalent in our models to a drop in friction coefficient by \textasciitilde 0.25\&\#8211;0.3 in fault zones. Thus, even a moderate frictional weakening, such as that allowed by the presence of lizardite in the fault zone (frictional strength of 0.45) enables large-offset (>15 km) faulting.},
    url = "https://doi.org/10.5194/egusphere-egu24-15593",
    doi = "10.5194/egusphere-egu24-15593",
    openalex = "W4392624399"
}