@article{crossref1903garden, title = "Garden Weeds", year = "1903", journal = "Scientific American", url = "https://doi.org/10.1038/scientificamerican08011903-38hbuild", doi = "10.1038/scientificamerican08011903-38hbuild", number = "2build", pages = "38-38", volume = "36" } @article{doi10108000167615908728505, author = "Wilson, Allan F. and Compston, W. and Jeffery, P. M. and Riley, G.H.", title = "Radioactive ages from the Precambrian rocks in Australia", year = "1959", journal = "Journal of the Geological Society of Australia", abstract = "Abstract The central nucleus of the Australian Precambrian shield lies in the western half of the continent and is characterized by striking similarities in structure and age over a vast area. Ages in the vicinity of 2,700 m.y. have been determined at many localities by the Rb/Sr and K/A methods. Flanking and cutting the shield are much younger belts of Precambrian rocks which have been fused onto the older shield. On the south‐eastern side, the deep‐seated Fraser Fault separates the Goldfields rocks (2,700 m.y.) from pegmatized basic charnockites (1,300 m.y.). In this region the shield rocks also show a metamorphism at 2,400 m.y. A similar structure separates the nucleus on the southern side from the east‐trending rocks of the south coast which were pegmatized about 1,400 m.y. ago. The western margin of the shield bounded by the Darling Fault shows evidence of vigorous recrystallization (about 650 m.y.) and regional magmatic activity (900 to 1,100 m.y.). A long E.‐W. 1,000 m.y. belt in central Australia may continue westward to divide the central nucleus of the shield. So far no basement rocks with ages in excess of 2,000 rn.y. have been found on this continent outside Western Australia. Granites in northern Australia appear to be at least 1,650 m.y. old, with a uranium mineralization at 500 m.y. In South Australia two periods of uranium mineralization have been recognized at 500 and 1,500 m.y. The 500 m.y. event is particularly well documented at Myponga, where there is agreement between the U/Pb, K/A and Rb/Sr ages of minerals from the main uranium lode channel. Lead mineralization at Broken Hill and Mount Isa also appears to have occurred in the vicinity of 1,500 m.y. ago. The major age divisions in Canada and Australia appear to be closely comparable.", url = "https://doi.org/10.1080/00167615908728505", doi = "10.1080/00167615908728505", openalex = "W2151096296" } @misc{doi104095328079, author = "Stockwell, C H", title = "Fourth report on structural provinces, orogenies, and time-classification of rocks of the Canadian Precambrian Shield", year = "1964", abstract = "The three previous progress reports (Stockwell 1961, 1963a, 1963b) summarized results up to the end of 1962. The present report adds results of work done since that time. A minor change has been made in the boundary of the Slave province, an additional orogeny has been added to the previous three, a new time-stratigraphic nomenclature is suggested in place of the cumbersome terminology of Lower, Middle, and Upper Proterozoic and their subdivisions, a few additional rock units have been placed in the time-stratigraphic classification, and new data pertaining to anomalous ages across the Grenville front are discussed.", url = "https://doi.org/10.4095/328079", doi = "10.4095/328079", openalex = "W3194184759" } @article{doi10108000167616508728585, author = "Leggo, P. J. and Compston, W. and Trendall, A. F.", title = "Radiometric ages of some precambrian rocks from the Northwest division of Western Australia", year = "1965", journal = "Journal of the Geological Society of Australia", abstract = "Abstract Rb‐Sr age measurements are reported for acid volcanic rocks, a tuffaceous siltstone, and two granites, all of Precambrian age, from the northwest division of Western Australia. The lava samples are from four localities within the Woongarra Volcanics, a formation situated near the top of the “Proterozoic” Hamersley Group, formerly a part of the “Nullagine Beds”. On field evidence these samples are of the same age, so that the Rb‐Sr data have been interpreted as giving approximately 2,100 m.y. for this age, assuming a variation in initial Sr87Sr86 of 0.700 to 0.720. The tuffaceous siltstone, from the overlying Wyloo Group, has a maximum indicated age of 1,850 m.y. This value is subject to uncertainty since only one sample was analysed, but nevertheless it is significantly younger than the Woongarra Volcanics, in accordance with its strati‐graphic position, and it is likewise consistent with concordant total‐rock and mineral ages of 1,720 m.y. measured in the Boolaloo Granite, which is intrusive into the Wyloo Group. Owing to suspected later metamorphism only broad limits of 2,300 to 3,000 m.y. can be set for the age of an “Archaean” granite which is older than the oldest “Proterozoic” sediments. Two unpublished U‐Pb and Rb‐Sr ages from the same area communicated to the authors are also reported.", url = "https://doi.org/10.1080/00167616508728585", doi = "10.1080/00167616508728585", openalex = "W2064000938" } @article{doi10108000167616508728586, author = "McDougall, Ian and Dunn, P. R. and Compston, W. and Webb, A. W. and Richards, John R. and Bofinger, V. M.", title = "Isotopic age determinations on precambrian rocks of the carpentaria region, Northern territory, Australia", year = "1965", journal = "Journal of the Geological Society of Australia", abstract = "Abstract A sequence up to 40,000 ft thick of unmetamorphosed and only slightly deformed sedimentary and volcanic rocks occurs in the Carpentaria Province of Northern Australia. Metamorphic and granitic rocks form the basement to this sequence, and K‐Ar and Rb‐Sr age measurements show that the basement granites are about 1,800 ± 50 m.y. old. Associated in space and time with the granitic rocks are acid volcanics which form the basal unit in the overlying sequence. Glauconites in sedimentary rocks from this succession yield dates ranging from 1,600 m.y. in the Tawallah Group, the second lowest unit, to about 1,390 m.y. in the Roper Group, the uppermost unit. Plagioclase and pyroxene from dolerites intrusive into the Roper Group give K‐Ar dates ranging from 1,100 to 1,280 m.y.; the older date provides a younger limit to the age of the Roper Group. Following slight folding the Wessel Group was deposited unconformably on the Roper Group; a single glauconite from the topmost formation of the Wessel Group yields concordant Rb‐Sr and K‐Ar dates of 780 ± 20 m.y. The results generally are internally consistent and provide much information, not previously available, as to the age of the Precambrian rocks in this region. Correlation with other Precambrian sequences in Australia now becomes possible as more dates are measured on rocks from other areas. Three alternatives are offered for the subdivision of Precambrian time in Australia; (i) the adoption of an arbitrary time‐scale independent of rock sequences, (ii) the adoption of the Canadian system of nomenclature, and (iii) the definition of standard time‐rock units for use throughout Australia. The third alternative is strongly recommended and such time‐rock units should be bounded by horizons that are amenable to accurate and precise dating by isotopic methods. By the judicious choice of several sequences it should be possible to obtain a satisfactory time scale for all Precambrian rocks in Australia. Part of the sequence developed in the Carpentaria Province is proposed as a time‐rock unit to be known as Carpentarian.", url = "https://doi.org/10.1080/00167616508728586", doi = "10.1080/00167616508728586", openalex = "W1982946410" } @article{doi10108000167616608728634, author = "Dunn, P. R. and Plumb, K.A. and Roberts, H. G.", title = "A proposal for time‐stratigraphic subdivision of the Australian Precambrian", year = "1966", journal = "Journal of the Geological Society of Australia", abstract = {Abstract Sufficient stratigraphic and radiometric data are now available to provide the basis for a time‐stratigraphic subdivision of the Precambrian in Australia. The data show that a major stratigraphic break occurred from about 2,600 to 2,300 m.y. and another at about 1,800 m.y., and that igneous activity was widespread from 2,700 to 2,600 m.y., and at about 1,800 m.y. and 1,500 m.y. Three largely unmetamorphosed rock sequences represent most of the time‐interval from 2,300 m.y., to the start of the Cambrian. The terms Archaean and Proterozoic are tentatively retained with a boundary dated at or before about 2,300 m.y. Time‐rock subdivision of the Proterozoic is proposed in terms of the three unmetamorphosed rock sequences deposited after 2,300 m.y. The oldest time‐rock unit is to be defined from the Hamersley Range area of Western Australia and is tentatively named the Lower Proterozoic ("Nullaginian") System with a base dated at about 2,300 m.y. The other units are the Carpentarian and Adelaidean Systems which have bases dated at about 1,800 m.y. and 1,400 m.y., respectively. The top of the Adelaidean System is defined by the base of the Cambrian. The boundaries between the proposed time‐rock units have ages comparable with those of boundaries between some overseas Precambrian subdivisions based on plutonic events.}, url = "https://doi.org/10.1080/00167616608728634", doi = "10.1080/00167616608728634", openalex = "W2020738636", references = "doi1010160012825266900407, doi101029jz067i009p03493, doi10108000167615908728505, doi10108000167616508728586, doi10108000167616608728611, doi1023071796421, doi102475ajs25811, openalexw577099667, openalexw630562038, openalexw654028833" } @article{doi10108011035896809451881, author = "Bowes, D. R.", title = "The absolute time scale and the subdivision of Precambrian rocks in Scotland", year = "1968", journal = "Geologiska Föreningen i Stockholm Förhandlingar", abstract = "Abstract The remnants of three major orogenic cycles have been recognised within the Lewisian complex of north-western Scotland, the Scourian, Inverian and Laxfordian orogenies having taken place, respectively, about 2600 + to 2460 m. y., 2200 to?2000 m. y. and 1600 to 1300 m. y. ago. After the deposition of the Torridonian (and Moine) series, the Knoydartian orogeny took place about?950 to 740 m. y. ago. Evidence from the Precambrian of Canada and the northern United States of America indicates the existence, of five orogenic episodes—2730 to 2450 m. y. (Kenoran), 2200 to 2100 m. y. (?Penokean), 1900 to 1700 m. y. (Hudsonian), 1520? to 1220? m. y. (Elsonian) and 1090 to 770 m. y. (Grenville). The marked correspondence of dates for the Precambrian orogenic episodes of Scotland and Canada and their similarity with those of peaks of world wide mineral ages (Gastil 1960) and with dates for orogenic episodes in Sweden (Welin 1966) and the Baltic Shield (Polkanov \& Gerling 1961) suggests an overall correlation: Scourian—Kenoran—Saamian, Inverian—?Penokean—Belomorian, Hudsonian—Svecofennian (Karelian), Laxfordian—Elsonian—Gothian, Knoydartian—Grenville—Sveconorwegian—Riphean. Such a correlation may form the basis of a subdivision of the Precambrian.", url = "https://doi.org/10.1080/11035896809451881", doi = "10.1080/11035896809451881", openalex = "W2085632940", references = "doi101038207054a0, doi101098rsta19650020, doi101139e66016, doi101144gsjgs11710233, doi101144gsjgs11910243, doi101144gsjgs12010153, doi101144gsljgs1950106010416, doi102475ajs25811, openalexw1601754258, openalexw589318775" } @article{doi1017491jgsi1969100201, author = "Crawford, A. R.", title = "Reconnaissance Rb-Sr Dating of the Precambrian Rocks of Southern Peninsular India", year = "1969", journal = "Journal of the Geological Society of India", abstract = "Abstract Many new Rb-Sr age determination analyses are reported for the crystalline complex of southern Peninsular India. These are mostly total-rock ages, often isochrons. Data are still insufficient for a reliable geochronology. Rocks of apparent ages ranging from over 3000 m.y. to 720 m.y. have been dated, and a lower Palaeozoic event reflected in mineral ages of about 500 m.y., known to have affected all Ceylon and much of the east coast of India, has been found as far north as Coimbatore. The oldest rocks have been found in Kerala, the Nilgiri Hills and southern Mysore. One age of 2700 m.y. has been found in Kerala. The craton of Mysore-Hyderabad has an age of at least 2585 ± 40 m.y., which is the apparent age of the Peninsular Gneiss over a wide area. The age of the Dharwar System remains uncertain, although the lavas near Chitradurga give an isochron at 2345 ± 60 m.y. The Chitradurga Granite has an age between 2450 and 2400 m.y. The Closepet Granite presents difficulties arising from its poor definition, but contains components between 2400 and 2000 m.y. Rocks of about 2100 m.y. occur in Kerala and western Tamizhagam, and could be present in Mysore, where an event at this time is recorded by biotite. The Chamundi Hill Granite of Mysore city, and a granite from the Ramanathapuram District of Tamizhagam give 790 ± 60 and 720 m.y. respectively, suggesting the possibility of widespread if sporadic intrusion in the southern half of the region at about this time. There is no real evidence yet of any major reflection of the Vijayan retrogressive metamorphism of Ceylon at 1140 m.y., except possibly in the intrusion of the Sivamalai soda-syenite. However, the known mineral ages of about 1690, 1650 and 1150 m.y. along the west coast suggest repeated marginal mobility of the Mysore-Hyderabad craton otherwise stable since about 2000 m.y. though intruded repeatedly by several dyke suites not yet dated. Much further sampling is needed, as well as the combination of several methods of dating. To facilitate this, modern geological and tectonic maps of medium scale are very desirable.", url = "https://doi.org/10.17491/jgsi/1969/100201", doi = "10.17491/jgsi/1969/100201", openalex = "W2279588601" } @article{doi1017741bgsf42017, author = "Rankama, Kalervo", title = "Proterozoic, Archeam and other weeds in the Precambrian rock garden", year = "1970", journal = "Bulletin of the Geological Society of Finland", abstract = "The use of the terms Precambrian; Proterozoic, Algonkian, and Archean; Cryptozoic and Archeozoic; and Eocambrian, Infracambrian, and Subcambrian is discussed. The Precambrian is no System in the sense of the Phanerozoic Systems but should be retained as the name of the longest recognized geochronologic unit and of the most extensive chronostratigraphic unit. A survey of literature and personal information received from Precambrian geologists in many parts of the world shows that the estimated age of the Proterozoic-Archean boundary ranges from about 3 000 Ma to about 1 700 Ma. The boundary is reasonably expected to be a worldwide isochronous boundary to which all Precambrian stratigraphers can return for reference. Unfortunately, it is not an isochronous boundary, and consensus as to its age seems to be impossible to reach. The Proterozoic and the Archean are recognized as valid terms only in their originally defined type areas. Their continued use as worldwide subdivisions of the Precambrian is not recommended. The other terms discussed are ill-defined, confusing, and meaningless. They should be discarded.", url = "https://doi.org/10.17741/bgsf/42.017", doi = "10.17741/bgsf/42.017", openalex = "W2750249593", references = "doi1010160012825266900407, doi101017s0016756800050445, doi101038187027d0, doi10108000167616608728629, doi10108000167616608728634, doi10108011035896809451881, doi101111j150239311974tb00901x, doi101139e68067, doi101139e68070, doi101306a663367c16c011d78645000102c1865d" } @article{rankama1970proterozoic, author = "Rankama, K.", title = "Proterozoic, Archeam and other weeds in the Precambrian rock garden", year = "1970", journal = "Bulletin of the Geological Society of Finland", url = "https://doi.org/10.17741/bgsf/42.017", doi = "10.17741/bgsf/42.017", pages = "211-222", volume = "42" } @techreport{rankama1970proterozoic1, author = "Rankama, K", title = "Proterozoic, Archean and other weeds in the Precambrian rock garden", year = "1970", howpublished = "Geological Society of Finland Bulletin, v. 42, p. 211-222", note = "talkorigins\_source = {true}; raw\_reference = {Rankama, K., 1970, Proterozoic, Archean and other weeds in the Precambrian rock garden: Geological Society of Finland Bulletin, v. 42, p. 211-222.}" } @article{doi101098rsta19730017, author = "Hoffman, Paul F.", title = "A Discussion on the evolution of the Precambrian crust - Evolution of an early Proterozoic continental margin: the Coronation geosyncline and associated aulacogens of the northwestern Canadian shield", year = "1973", journal = "Philosophical Transactions of the Royal Society of London Series A Mathematical and Physical Sciences", abstract = "Abstract The Coronation geosyncline developed in the early Proterozoic along the western margin of a continental platform (the Slave Province) of Archaean rocks older than 2300 Ma, and culminated between 1725 and 1855 Ma ago with the emplacement of a pair of batholiths (the Bear Province). The evolution of the geosyncline has a strong family resemblance to Phanerozoic geosynclines believed to delineate ancient continental margins and have been controlled by global plate interactions. Such geosynclines are unknown in Archaean orogenic belts, from which it is inferred that creation of the first large rigid continental platforms marked the end of the Archaean and the beginnings of actualistic plate tectonics. The geosyncline began with deposition of a westward-facing continental shelf, consisting of a lower formation dominated by orthoquartzite, derived from the platform, and an upper cyclic stromatolitic dolomite formation. West of the shelf edge, the dolomite passes abruptly into a much thinner mudstone sequence with dolomite debris-flows, and the orthoquartzite into a thick laminated silt and mudstone sequence with quartzite turbidites. The oldest rocks west of the shelf edge, an area interpreted to have been a continental rise, are pillow basalts and volcanic breccias, extruded above a basement of unknown character. The principal turning point in the evolution of the geosyncline came with the foundering of the continental shelf. It is draped by a thin laminated pyritic black mudstone sequence, overlain by a westward-thickening clastic wedge resulting from intrusion and erosion of the batholiths to the west. The clastic wedge begins with a thick sequence of coarse greywacke turbidites that passes eastward into concretionary mudstone on the platform. The mudstone grades upward into laminated shaly limestone with minor greywacke turbidites, overlain in turn by cross-bedded red lithic sandstone. The supracrustal rocks of the geosyncline have been compressed and tectonically transported toward the platform. Adjacent to the batholithic belt, the continental rise and clastic wedge sequences are penetratively deformed and recrystallized by regional low-pressure metamorphism. To the east, the unmetamorphosed continental shelf and clastic wedge sequences have been flexurally folded and overthrust above a basal detachment surface. East of the thrust zone, relatively thin rocks on the platform are nearly flat-lying except around large anticlinal basement uplifts. Unusual features of the platform are its two aulacogens - long-lived deeply subsiding fault troughs that extend at high angles from the geosyncline far into the interior of the platform. During every phase in the evolution of the geosyncline, the aulacogens received much thicker sedimentary sequences, commonly with the addition of basaltic volcanics, than adjacent parts of the platform. Although equal in thickness to the geosyncline, the aulacogens were never subjected to the batholithic intrusions, regional metamorphism or low-angle overthrusting characteristic of the geosyncline. The Athapuscow aulacogen, in the region of Great Slave Lake, is interpreted as having been an incipient rift, located over a crustal arch, during the continental shelf stage of the geosyncline, but sagged to become a crustal downwarp during the clastic wedge stage, ultimately with sufficient transverse compression to produce broad folds. Finally, the aulacogen became part of a regional transcurrent fault system, along which thick fanglomerates accumulated in local troughs. The batholithic belt consists of two batholiths, eroded to different depths, separated by the northtrending 350 km long Wopmay River fault. The Hepburn batholith, east of the fault, is a composite intrusion of mesozonal granodiorite plutons. The foliated and migmatitic borders of the plutons are normally concordant with wall rock sheaths of sillimanitic paragneiss. Along the eastern margin of the batholith, metamorphosed rocks of the continental rise sequence dip gently to the west beneath the batholithic rocks. Belts of intensely deformed and metamorphosed supracrustal rocks within the batholithic terrain include sequences of pillow basalt, pelites and granite-pebble conglomerate, perhaps the lower part of the continental rise deposited during the initial rifting of the continental margin. The Great Bear batholith, west of the fault, consists of discordant epizonal plutons, mostly adamellite, that intrude broadly folded but regionally unmetamorphosed sequences of welded rhyodacitic ash-flow tuff, trachybasalt and derived sedimentary rocks. The volcanic rocks, intruded by dense dyke swarms radiating from the plutons and by felsite plugs, are interpreted to be comagmatic with the plutons. Mapping is as yet insufficient to establish, speculations aside, the possible relations of the two batholiths to arc-trench systems. Furthermore, the western margin of the batholithic belt, a region of critical importance, is covered by a veneer of younger Proterozoic and Paleozoic sedimentary rocks. Until fossil arc-trench systems are outlined, the contention that the Coronation Geosyncline involved global plate interactions is based on indirect evidence - the analogous evolution of the geosyncline east of the batholithic belt with Phanerozoic geosynclines in which fossil arc-trench systems have been found.", url = "https://doi.org/10.1098/rsta.1973.0017", doi = "10.1098/rsta.1973.0017", openalex = "W2162782076" } @article{doi101098rsta19760015, author = "Schmus, W. R. Van", title = "A Discussion on global tectonics in Proterozoic times - Early and Middle Proterozoic history of the Great Lakes area, North America", year = "1976", journal = "Philosophical Transactions of the Royal Society of London Series A Mathematical and Physical Sciences", abstract = "Abstract Two major supracrustal sequences, the Huronian Supergroup in Ontario and the Marquette Range Supergroup and Animikie Group of Michigan and Minnesota, overlie an Archean basement. These sequences are about 2200—2300 Ma and 1900-2000 Ma old respectively. The major Early Proterozoic tectonic event is the ‘Penokean Orogeny’, which occurred about 1850-1900 Ma ago and included deformation, high-grade regional metamorphism, and extrusive and intrusive igneous activity. This was followed by formation of rhyolitic, ignimbritic volcanic rocks and emplacement of associated granites about 1790 Ma ago. The entire region was subsequently subjected to low-grade regional metamorphism 1650-1700 Ma ago, followed by emplacement of anorogenic quartz-monzonite, in part rapakivi, plutons 1500 Ma ago. Late Proterozoic Grenville and Keweenawan events represent the youngest major Precambrian activity in the region. The rocks involved in the Penokean Orogeny lie along the southern margin of the Archean craton of the Superior Province and are interpreted as representing Early Proterozoic cratonic-margin orogenic activity. The distribution of rocks types and structures associated with the Penokean Orogeny and with similar orogenic belts along the margin of the Archean craton of North America suggest that these orogenic belts may have formed as a result of processes similar to modern plate tectonics, although the data are far from conclusive at present.", url = "https://doi.org/10.1098/rsta.1976.0015", doi = "10.1098/rsta.1976.0015", openalex = "W2146453254", references = "doi101139e68070" } @article{doi103133pp902, author = "King, Philip B.", title = "Precambrian geology of the United States; an explanatory text to accompany the geologic map of the United States", year = "1976", journal = "USGS professional paper", abstract = "Precambrian rocks are at the surface in about 10 percent of the area of the United States, but are more extensive beneath the Phanerozoic rocks, especially in the Central Interior Region. Exposures occur in southward-projecting parts of the Canadian Shield in the Lake Superior Region and Adirondack Mountains, and in smaller inliers farther south in the Central Interior. Precambrian rocks emerge in the higher uplifts produced by Phanerozoic deformations in the Appalachian and Cordilleran mountain belts to the east and west, but are very scantily represented c;lose to the Pacific Coast.", url = "https://doi.org/10.3133/pp902", doi = "10.3133/pp902", openalex = "W176268222", references = "doi101038physci240078a0, doi10113000167606196273139lcswmc20co2, doi10113000167606196374991paotcm20co2, doi10113000167606197182581nacosu20co2, doi101130001676061972831215pbbonu20co2, doi101130gsab10199, doi102475ajs25811, doi102475ajs26791017, doi103133pp866, openalexw1583108281" } @misc{crossref2004proterozoic, title = "Proterozoic (Precambrian)", year = "2004", booktitle = "Encyclopedic Dictionary of Genetics, Genomics and Proteomics", url = "https://doi.org/10.1002/0471684228.egp10176", doi = "10.1002/0471684228.egp10176" } @incollection{robb2005the, author = "Robb, L. J. and Knoll, A. H. and Plumb, K. A. and Shields, G. A. and Strauss, H. and Veizer, J.", title = "The Precambrian: the Archean and Proterozoic Eons", year = "2005", booktitle = "A Geologic Time Scale 2004", url = "https://doi.org/10.1017/cbo9780511536045.010", doi = "10.1017/cbo9780511536045.010", pages = "129-140" } @article{sergeev2007principal, author = "Sergeev, V. N. and Semikhatov, M. A. and Fedonkin, M. A. and Veis, A. F. and Vorob’eva, N. G.", title = "Principal stages in evolution of Precambrian organic world: Communication 1. Archean and Early Proterozoic", year = "2007", journal = "Stratigraphy and Geological Correlation", url = "https://doi.org/10.1134/s0869593807020025", doi = "10.1134/s0869593807020025", number = "2", pages = "141-160", volume = "15" } @incollection{crossref2008proterozoic, title = "Proterozoic (precambrian)", year = "2008", booktitle = "Encyclopedia of Genetics, Genomics, Proteomics and Informatics", url = "https://doi.org/10.1007/978-1-4020-6754-9\_13668", doi = "10.1007/978-1-4020-6754-9\_13668", pages = "1588-1588" } @article{doi101134s0869593810050011, author = "Чумаков, Н. М.", title = "Precambrian glaciations and associated biospheric events", year = "2010", journal = "Stratigraphy and Geological Correlation", abstract = "Precambrian glaciations are established to have occured during several brief periods in the Late Archean, Early Proterozoic, Late Riphean, and Vendian. These extreme climatic events of the Late Archean and post-Archean Earth history were accompanied by significant changes in the biosphere and biota. The terminal stages of Precambrian glaciations were marked by intense development of some existing groups, and the appearance of new groups of organisms. This may be explained by associated radical transformations of environments in all the biosphere subsystems, which resulted in substantial ecosystem and related biotic crises. The crises released former and yielded new ecological niches, on the one hand, and provoked enhanced mutations in organisms and rapid appearance of new forms, on the other. The most viable new forms as well as some of taxa that survived the crisis colonized released and newly formed niches to become more diverse and dominant groups. Thus, activation of abiotic and subsequent biotic factors during and after glaciations stimulated the renewal of the biota and acceleration of the evolutionary process.", url = "https://doi.org/10.1134/s0869593810050011", doi = "10.1134/s0869593810050011", openalex = "W1971382444", references = "sergeev2007principal" } @article{doi101134s0869593810060018, author = "Sergeev, V. N. and Semikhatov, M. A. and Fedonkin, M. and Vorob’eva, N. G.", title = "Principal stages in evolution of precambrian organic world: Communication 2. The late proterozoic", year = "2010", journal = "Stratigraphy and Geological Correlation", url = "https://www.semanticscholar.org/paper/9f1978d9869ee88f618032bc1b254a510e093b28", doi = "10.1134/S0869593810060018", is_oa = "true", number = "6", pages = "561-592", semanticscholar_citation_count = "40", semanticscholar_id = "9f1978d9869ee88f618032bc1b254a510e093b28", volume = "18" } @incollection{arndt2011archean, author = "Arndt, Nicholas and Pinti, Daniele L.", title = "Archean Mantle", year = "2011", booktitle = "Encyclopedia of Astrobiology", url = "https://doi.org/10.1007/978-3-642-11274-4\_99", doi = "10.1007/978-3-642-11274-4\_99", pages = "69-69" } @article{fedonkin2018pseudofossils, author = "Fedonkin, M. A. and Sergeev, V. N.", title = "Pseudofossils, Contaminants, and Other Hazards in Archean and Proterozoic Micropaleontology", year = "2018", journal = "Stratigraphy and Geological Correlation", url = "https://doi.org/10.1134/s0869593818030061", doi = "10.1134/s0869593818030061", number = "3", pages = "364-365", volume = "26" } @article{doi101144jgs2020222, author = "Shields, Graham and Strachan, Robin A. and Porter, Susannah M. and Halverson, Galen P. and Macdonald, Francis A. and Plumb, K.A. and de Alvarenga, Carlos José Souza and Banerjee, D. M. and Bekker, Andrey and Bleeker, Wouter and Brasier, Martin and Chakraborty, Partha Pratim and Collins, Alan S. and Condie, Kent C. and Das, Kaushik and Evans, David A.D. and Ernst, Richard E. and Fallick, Anthony E. and Frimmel, Hartwig E. and Fuck, Reinhardt A. and Hoffman, Paul F. and Kamber, Balz S. and Кузнецов, А. Б. and Mitchell, Ross N. and Poiré, Daniel G. and Poulton, Simon W. and Riding, Robert and Шарма, Мукунд and Storey, Craig and Stüeken, Eva E. and Tostevin, Rosalie and Turner, Elizabeth C. and Xiao, Shuhai and Zhang, Shuan‐Hong and Zhou, Ying and Zhu, Maoyan", title = "A template for an improved rock-based subdivision of the pre-Cryogenian timescale", year = "2021", journal = "Journal of the Geological Society", abstract = "The geological timescale before 720 Ma uses rounded absolute ages rather than specific events recorded in rocks to subdivide time. This has led increasingly to mismatches between subdivisions and the features for which they were named. Here we review the formal processes that led to the current timescale, outline rock-based concepts that could be used to subdivide pre-Cryogenian time and propose revisions. An appraisal of the Precambrian rock record confirms that purely chronostratigraphic subdivision would require only modest deviation from current chronometric boundaries, removal of which could be expedited by establishing event-based concepts and provisional, approximate ages for eon-, era- and period-level subdivisions. Our review leads to the following conclusions: (1) the current informal four-fold Archean subdivision should be simplified to a tripartite scheme, pending more detailed analysis, and (2) an improved rock-based Proterozoic Eon might comprise a Paleoproterozoic Era with three periods (early Paleoproterozoic or Skourian, Rhyacian, Orosirian), Mesoproterozoic Era with four periods (Statherian, Calymmian, Ectasian, Stenian) and a Neoproterozoic Era with four periods (pre-Tonian or Kleisian, Tonian, Cryogenian and Ediacaran). These proposals stem from a wide community and could be used to guide future development of the pre-Cryogenian timescale by international bodies.", url = "https://doi.org/10.1144/jgs2020-222", doi = "10.1144/jgs2020-222", openalex = "W3171350420", references = "doi1010160301926874900084, doi1010160301926878900384, doi101016b978012824360200019x, doi10108000167616608728629, doi10108000167616608728634, doi101139e68070, doi101306819a40b816c511d78645000102c1865d, robb2005the" } @inproceedings{liu2022archean, author = "Liu, Chuntao and Keller, C. Brenhin and He, Yongsheng and Zhang, Zhou", title = "Archean to Proterozoic hard rock geochemistry: a refined database", year = "2022", booktitle = "Goldschmidt2022 abstracts", url = "https://doi.org/10.46427/gold2022.9774", doi = "10.46427/gold2022.9774" } @article{doi101002mlf270066, author = "Tang, Lingyun and Luo, Zhenhao and Gao, Shaoming and Lin, Zhiliang and Sun, Mengqi and Li, Runsheng and Gao, Shu-Hong and Wu, Geng and Li, Yiliang and Huang, Linan and Fan, Lu", title = "A hot origin of dissimilatory sulfite reduction catalyzed by DsrAB in the Paleoarchean Era.", year = "2026", journal = "mLife", abstract = "Dissimilatory sulfite reduction (DSR) has been essential to microbial energy metabolism in the biogeochemical sulfur cycle since the Paleoarchean Era. However, due to the lack of an integrated assessment of geological record and genomic data, the evolutionary origin of DSR remains elusive in terms of time, habitat, and genetic basis. In this study, we reconstructed the evolutionary pathways and the ancestral sequences of Dsr proteins by mining metagenomes ranging from mesothermal to hyperthermal environments. A phylogenetic analysis of the key catalytic enzyme, DsrAB, and other Dsr proteins indicates that the earliest and most basic functional cascade, DsrABCNM, emerged prior to the latest common ancestor of several basal branching DsrAB clusters encoded by bacteria and archaea. Using a molecular dating strategy that calibrates the protein tree with a species tree, we predicted that the DSR originated 3.508 billion years ago (Ga). This finding strongly confirms the earliest geological evidence of DSR (\textasciitilde\ 3.47 Ga). Further predictions from ancestral sequence reconstruction indicate that the optimal catalytic temperature of DsrA at the time of DSR origin was approximately 73°C, which is consistent with the petrographic and geochemical evidence in early Archean hydrothermal deposits. After its hot origin, DsrA diversified into subclades that adapted to various temperature levels following the Great Oxidation Event. This is exemplified by the evolution of the reductive archaeal-type DsrA. Our results synchronize the molecular ages with the geological record, which advances our understanding of the earliest DSR systems and highlights the enzymatic adaptations of microbial life in the Archean biosphere.", url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC12948486/", doi = "10.1002/mlf2.70066", pmcid = "PMC12948486", pmid = "41767950" } @article{doi101038s4146702669826x, author = "Dreher, Carolin L and Cirpka, Olaf A and Schad, Manuel and Konhauser, Kurt O and Kappler, Andreas", title = "Survival of cyanobacteria and mitigation of Fe(II) toxicity effects in a silica-rich Archean ocean.", year = "2026", journal = "Nature communications", abstract = "Banded iron formations (BIF) were deposited abundantly between 2.7-2.4 Ga from iron- and silica-rich oceans, with cyanobacterial oxygen (O2) as a possible oxidant for Fe(II)(aq) oxidation and Fe(III) oxyhydroxide precipitation. However, toxic reactive oxygen species (ROS) from Fe(II)/O2 interactions might have inhibited cyanobacterial growth, contributing to the delay between cyanobacterial evolution (>3.0 Ga) and the Great Oxidation Event (2.5 Ga). Here, we explored the impact of Fe(II)(aq) and SiO2(aq) on Synechococcus sp. PCC 7002. High Fe(II)(aq) (> 500 µM) increased ROS formation, but elevated SiO2(aq) (2200 µM) suppressed ROS formation, promoting growth and O2 production. Diel light cycles further reduced ROS formation compared to continuous illumination. Modelling O2 distribution based on experimental rates revealed oxygenated surface waters at relevant upwelling rates. Together, our results indicate that high SiO2(aq) and day-night-light cycles in Archean oceans mitigated ROS stress, enabling cyanobacterial proliferation and enhancing their role in Earth's oxygenation and BIF deposition.", url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC12932812/", doi = "10.1038/s41467-026-69826-x", pmcid = "PMC12932812", pmid = "41723153" } @article{doi101073pnas2525466123, author = "Houchin, Shane K and Tissot, François L H and Ibañez-Mejia, Mauricio and Bell, Elizabeth A and Harrison, T Mark and Newville, Matthew and Lanzirotti, Antonio", title = "Oxidized Hadean magmas and Archean mobile-lid tectonics revealed by Jack Hills zircon.", year = "2026", journal = "Proceedings of the National Academy of Sciences of the United States of America", abstract = "Mobile-lid tectonics is a first-order feature characterizing the modern Earth, yet its origins remain enigmatic due to a scarcity of ancient terrestrial materials. Detrital zircons provide the most complete archive of Earth's early crust and preserve the only record extending beyond \textasciitilde 4.0 Ga. Here, we combine U XANES oxybarometry with U-Pb and trace element analysis to investigate the igneous cores and metamorphic rims of Hadean-Archean zircon from the Jack Hills, Australia. Igneous cores record consistent, moderately oxidized magma conditions (FMQ-1 to +1), challenging notions of a highly reduced early Earth and supporting models that evoke efficient mantle convection throughout the Hadean. In contrast, redox states and trace element contents show that metamorphic rims record i) high-ƒO2 and high-intermediate T/P conditions (FMQ+1.6 to +2.5; >600 °C/GPa) and ii) low-ƒO2 and generally lower T/P conditions (FMQ-0.2 to +0.5; <500 °C/GPa). While only high T/P conditions are observed in Hadean zircon rims, Archean rims (\textasciitilde 3.35 Ga) preserve both the low and high T/P signatures, a pattern typical of large-scale plate underthrusting. These findings imply Earth's mantle had near-modern redox states by 4.15 Ga and that mobile-lid tectonics was active by the early Archean, at the latest.", url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC12974523/", doi = "10.1073/pnas.2525466123", pmcid = "PMC12974523", pmid = "41770924" }