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Journal articles on the topic 'Proterozoicum'

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Published: 4 June 2021

Last updated: 14 February 2022

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1

Kemnitz, Helga, Bodo-Carlo Ehling, Olaf Elicki, et al. "Proterozoikum–Silur in der Stratigraphischen Tabelle von Deutschland 2016 The Stratigraphic Table of Germany 2016: Proterozoic to Silurian." Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 168, no. 4 (2018): 423–46. http://dx.doi.org/10.1127/zdgg/2017/0134.

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2

Leonhardt, Dietmar, Thomas Heuse, Klaus Hoth, Karl-Armin Tröger, and Jörg Maletz. "Der Zeitabschnitt Proterozoikum Silur in der Stratigraphischen Tabelle von Deutschland 2002." Newsletters on Stratigraphy 41, no. 1-3 (2006): 25–42. http://dx.doi.org/10.1127/0078-0421/2005/0041-0025.

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3

Rogers, John. "Proterozoic supercontinents." International Geology Review 53, no. 11-12 (2011): 1263–64. http://dx.doi.org/10.1080/00206814.2010.528185.

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4

Friderichsen, J. D., N. Henriksen, and R. A. Strachan. "Basement-cover relationships and regional structure in the Grandjean Fjord - Bessel Fjord region (75°–76°N), North-East Greenland." Rapport Grønlands Geologiske Undersøgelse 162 (January 1, 1994): 17–33. http://dx.doi.org/10.34194/rapggu.v162.8246.

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Geological mapping and isotopic investigations demonstrate that the Grandjean Fjord – Bessel Fjord region can be divided into three rock groups: (1) a Lower Proterozoic basement gneiss complex; (2) a Middle Proterozoic supracrustal cover (Smallefjord sequence); and (3) Upper Proterozoic metasediments (Eleonore Bay Supergroup). The basement gneiss complex largely comprises c. 2.0–1.7 Ga calc-alkaline granitoid orthogneisses with intercalated migmatitic supracrustal rocks. The complex is deformed by at least two sets of approximately coaxial folds which may be either Proterozoic or Caledonian in

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5

Cowie, J. W. "Proterozoic geology: Selected papers from an international proterozoic symposium." Earth-Science Reviews 23, no. 1 (1986): 67–68. http://dx.doi.org/10.1016/0012-8252(86)90009-7.

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6

Bucholz, Claire E., and Christopher J. Spencer. "Strongly Peraluminous Granites across the Archean–Proterozoic Transition." Journal of Petrology 60, no. 7 (2019): 1299–348. http://dx.doi.org/10.1093/petrology/egz033.

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Abstract Strongly peraluminous granites (SPGs) form through the partial melting of metasedimentary rocks and therefore represent archives of the influence of assimilation of sedimentary rocks on the petrology and chemistry of igneous rocks. With the aim of understanding how variations in sedimentary rock characteristics across the Archean–Proterozoic transition might have influenced the igneous rock record, we compiled and compared whole-rock chemistry, mineral chemistry, and isotope data from Archean and Paleo- to Mesoproterozoic SPGs. This time period was chosen as the Archean–Proterozoic tr

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7

Hurley, Sarah J., Boswell A. Wing, Claire E. Jasper, Nicholas C. Hill, and Jeffrey C. Cameron. "Carbon isotope evidence for the global physiology of Proterozoic cyanobacteria." Science Advances 7, no. 2 (2021): eabc8998. http://dx.doi.org/10.1126/sciadv.abc8998.

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Ancestral cyanobacteria are assumed to be prominent primary producers after the Great Oxidation Event [≈2.4 to 2.0 billion years (Ga) ago], but carbon isotope fractionation by extant marine cyanobacteria (α-cyanobacteria) is inconsistent with isotopic records of carbon fixation by primary producers in the mid-Proterozoic eon (1.8 to 1.0 Ga ago). To resolve this disagreement, we quantified carbon isotope fractionation by a wild-type planktic β-cyanobacterium (Synechococcus sp. PCC 7002), an engineered Proterozoic analog lacking a CO2-concentrating mechanism, and cyanobacterial mats. At mid-Prot

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8

Carver, J. H., and I. M. Vardavas. "Precambrian glaciations and the evolution of the atmosphere." Annales Geophysicae 12, no. 7 (1994): 674–82. http://dx.doi.org/10.1007/s00585-994-0674-3.

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Abstract. Precambrian glaciations appear to be confined to two periods, one in the early Proterozoic between 2.5 and 2 Gyears BP (Before Present) and the other in the late Proterozoic between 1 and 0.57 Gyear BP. Possible reasons for these broad features of the Precambrian climate have been investigated using a simple model for the mean surface temperature of the Earth that partially compensates for the evolution of the Sun by variations in the atmospheric CO2 content caused by outgassing, the formation of continents and the weathering of the Earth's land surface. It is shown that the model ca

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9

Jepsen, H. F., J. C. Escher, J. D. Friderichsen, and A. K. Higgins. "The geology of the north-eastern corner of Greenland - photogeological studies and 1993 field work." Rapport Grønlands Geologiske Undersøgelse 161 (January 1, 1994): 21–33. http://dx.doi.org/10.34194/rapggu.v161.8240.

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Late Archaean and Early Proterozoic crust-forming events in North-East and eastern North Greenland were succeeded by Middle Proterozoic sedimentation and volcanic activity; Late Proterozoic through Tertiary sedimentation was interrupted by several periods of tectonic activity, including the Caledonian orogeny in East Greenland and the Mesozoic deformation of the Wandel Hav mobile belt. Photogeological studies helped pinpoint areas of special interest which were investigated during the short 1993 field season. Insights gained during field work include: the nature of the crystalline basement ter

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10

Dawes, P. R. "Etah meta-igneous complex and the Wulff structure: Proterozoic magmatism and deformation in Inglefield Land, North-West Greenland." Rapport Grønlands Geologiske Undersøgelse 139 (December 31, 1988): 1–24. http://dx.doi.org/10.34194/rapggu.v139.8021.

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A hitherto uninvestigated collection of crystalline rocks from north-eastem Inglefield Land (c. 79°N) allowanew interpretation of the Precambrian geology of the region. The majority of the samples - high-grade basic, intermediate and granitoid rocks - are referred to the Etah meta-igneous complex, which has been shown to be mid-Proterozoic in age in the type area in south-western Inglefield Land. In areas of high deformation there is a gradation from massive rocks of igneous aspect into folded and variably migmatised gneisses. Thus the magmatic complex provides a gauge of the nature and intens

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11

Baadsgaard, H. "Proterozoic crustal evolution." Chemical Geology 112, no. 1-2 (1994): 197. http://dx.doi.org/10.1016/0009-2541(94)90116-3.

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12

Butterfield, Nicholas J. "Probable Proterozoic fungi." Paleobiology 31, no. 1 (2005): 165–82. http://dx.doi.org/10.1666/0094-8373(2005)031<0165:ppf>2.0.co;2.

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13

Schidlowski, Manfred. "Proterozoic carbon cycle." Nature 362, no. 6416 (1993): 117–18. http://dx.doi.org/10.1038/362117b0.

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14

Des Marals, David J., Harald Strauss, Roger E. Summons, and J. M. Hayes. "Proterozoic carbon cycle." Nature 362, no. 6416 (1993): 118. http://dx.doi.org/10.1038/362118a0.

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15

Kröner, Alfred. "Proterozoic Lithospheric Evolution." Eos, Transactions American Geophysical Union 69, no. 16 (1988): 244. http://dx.doi.org/10.1029/88eo00138.

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16

Jahn, Bor-Ming. "Proterozoic crustal evolution." Tectonophysics 227, no. 1-4 (1993): 227–30. http://dx.doi.org/10.1016/0040-1951(93)90099-6.

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17

Berthelsen, Asger. "Proterozoic Crustal Evolution." Precambrian Research 70, no. 1-2 (1994): 166–67. http://dx.doi.org/10.1016/0301-9268(94)90026-4.

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18

Hanmer, Simon, Michael Williams, and Chris Kopf. "Striding-Athabasca mylonite zone: implications for the Archean and Early Proterozoic tectonics of the western Canadian Shield." Canadian Journal of Earth Sciences 32, no. 2 (1995): 178–96. http://dx.doi.org/10.1139/e95-015.

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Study of the northern Saskatchewan–District of Mackenzie segment of the Snowbird tectonic zone suggests that fragments of relatively stiff mid-Archean crust, possibly arc related, have controlled the localization, shape, and complex kinematics of the multistage Striding–Athabasca mylonite zone during the Archean, as well as the geometry of the Early Proterozoic rifted margin of the western Churchill continent. By the late Archean, the Striding–Athabasca mylonite zone was located in the interior of the western Churchill continent, well removed from the contemporaneous plate margins. Except for

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19

Bertrand, Jean Michel, and Emmanuel Ferraz Jardim de Sá. "Where are the Eburnian–Transamazonian collisional belts?" Canadian Journal of Earth Sciences 27, no. 10 (1990): 1382–93. http://dx.doi.org/10.1139/e90-148.

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The reconstruction of Early Proterozoic crustal evolution and geodynamic environments, in Africa and South America, is incomplete if cratonic areas alone are studied. If the presence of high-grade gneisses is considered as a first clue to past collisional behaviour, 2 Ga high-grade gneisses are more abundant within the Pan-African–Brasiliano mobile belts than in the intervening pre-Late Proterozoic cratons. The West African craton and the Guiana–Amazonia craton consist of relatively small Archaean nuclei and widespread low- to medium-grade volcanic and volcanoclastic formations intruded by Ear

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20

Klasner, J. S., and E. R. King. "Precambrian basement geology of North and South Dakota." Canadian Journal of Earth Sciences 23, no. 8 (1986): 1083–102. http://dx.doi.org/10.1139/e86-109.

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Combined analysis of drill-hole, gravity, and magnetic data indicates that the buried Precambrian basement rocks of the Dakotas can be divided into several lithotectonic terranes. Eastern North Dakota and northeastern South Dakota are underlain by Archean gneiss. Except for the Black Hills region of South Dakota, where Archean rocks are also exposed, the western third of both Dakotas is underlain mainly by Early Proterozoic gneiss and metasedimentary rocks. Part of this region is underlain by Archean crust with an Early Proterozoic tectonic overprint. A broad transition zone of strongly overpr

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21

Mercier, Éric. "Évènements tectoniques d'origine compressive dans le Protérozoïque du nord de la Cordillère canadienne (montagnes Ogilvie, Yukon)." Canadian Journal of Earth Sciences 26, no. 1 (1989): 199–205. http://dx.doi.org/10.1139/e89-016.

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The oldest Proterozoic strata of Coal Creek Dome (Ogilvie Mountains, Yukon) have been affected by syntectonic and decimetre- to kilometre-scale folds. These folds were eroded, then sealed by other Proterozoic strata. This is the first record of a Proterozoic compressive tectonic event in the northern Canadian Cordillera. It is named the Fifteenmile orogeny and may be correlated either with the Wernecke Mountains Racklan orogeny (usually dated at about 1200 Ma) or with an older event, perhaps Hudsonian (1750 Ma).

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22

Grenfell, John Lee, Barbara Stracke, Beate Patzer, Ruth Titz, and Heike Rauer. "Potential of ozone formation by the smog mechanism to shield the surface of the early Earth from UV radiation." International Journal of Astrobiology 5, no. 4 (2006): 295–306. http://dx.doi.org/10.1017/s1473550406003478.

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We propose that the photochemical smog mechanism produced substantial ozone (O3) in the troposphere during the Proterozoic period, which contributed to ultraviolet (UV) radiation shielding, and hence favoured the establishment of life. The smog mechanism is well established and is associated with pollution hazes that sometimes cover modern cities. The mechanism proceeds via the oxidation of volatile organic compounds such as methane (CH4) in the presence of UV radiation and nitrogen oxides (NOx). It would have been particularly favoured during the Proterozoic period given the high levels of CH

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23

Kerr, Andrew, and Richard J. Wardle. "Definition of an Archean – Proterozoic crustal suture by isotopic studies of basement intersections from offshore wells in the southern Labrador Sea." Canadian Journal of Earth Sciences 34, no. 2 (1997): 209–14. http://dx.doi.org/10.1139/e17-017.

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Eight hydrocarbon exploration wells in the southern Labrador Sea penetrated Precambrian basement rocks, adjacent to the course of a Lithoprobe marine seismic reflection survey. The rock types are mostly Early Proterozoic (1870–1800 Ma) calc-alkaline plutonic rocks or their metamorphic derivatives, but one example is a Middle Proterozoic (1270 Ma) anorogenic intrusion. These samples of buried basement document a transition from juvenile Proterozoic crust in the southeast (shown by εNd from +0.8 to +2.2) to ancient Archean crust in the northwest (shown by εNd from −2.7 to −7.0). However, initial

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24

Sønderholm, M., and H. F. Jepsen. "Proterozoic basins of North Greenland." Bulletin Grønlands Geologiske Undersøgelse 160 (January 1, 1991): 49–69. http://dx.doi.org/10.34194/bullggu.v160.6713.

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Proterozoic sedimentary and associated igneous rocks along the margin of the Precambrian crystalline shield in North Greenland have been studied by several geological field-teams since 1912 when they were first investigated during the First Thule Expedition. More recently, the Proterozoic strata of North Greenland have been studied in greater detail by the Geological Survey of Greenland (GGU) during the North Greenland Project of 1978-80 and 1983-85. The present paper reviews these studies in an attempt to elucidate the development of the sedimentary basins in North Greenland during the Proter

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25

Dawes, Peter R., Ole Larsen, and Feiko Kalsbeek. "Archean and Proterozoic crust in North-West Greenland: evidence from Rb–Sr whole-rock age determinations." Canadian Journal of Earth Sciences 25, no. 9 (1988): 1365–73. http://dx.doi.org/10.1139/e88-131.

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The geochronological understanding of the Precambrian crystalline shield of North-West Greenland (75–79°N) is at a rudimentary stage. Isotopic data from three major rock complexes—the Etah meta-igneous complex, the Kap York meta-igneous complex, and the Kivioq Havn gneiss and supracrustal complex—all show scatter indicating disturbed Rb–Sr isotope systems. This may reflect widespread reactivation of the crust in Proterozoic (Hudsonian) time. However, the majority of the samples define errorchrons that are regarded as geologically significant, and although the ages are poorly constrained, the d

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26

Townson, W. G. "THE SUBSURFACE GEOLOGY OF THE WESTERN OFFICER BASIN — RESULTS OF SHELL'S 1980-1984 PETROLEUM EXPLORATION CAMPAIGN." APPEA Journal 25, no. 1 (1985): 34. http://dx.doi.org/10.1071/aj84003.

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The Officer Basin described in this paper includes four Proterozoic to Lower Palaeozoic sub-basins (Gibson, Yowalga, Lennis, Waigen) which extend in a northwest to southeast belt across 200 000 sq. km of central Western Australia. These sub-basins are bounded by Archaean to Proterozoic basement blocks and are almost entirely concealed by a veneer of Permian and Cretaceous sediments. Depth to magnetic basement locally exceeds eight kilometres.Until recently, information on the sub-surface geology was limited to shallow levels, based on the results of a petroleum exploration campaign in the 1960

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27

Roscoe, S. M., and K. D. Card. "The reappearance of the Huronian in Wyoming: rifting and drifting of ancient continents." Canadian Journal of Earth Sciences 30, no. 12 (1993): 2475–80. http://dx.doi.org/10.1139/e93-214.

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Striking stratigraphic and sedimentological similarities between the Early Proterozoic Huronian Supergroup of the Canadian Shield and the Snowy Pass Supergroup of Wyoming suggest that they were deposited in a single, broad, epicratonic basin developed atop a large Archean continent that included the Superior and Wyoming geological provinces. Breakup of the continent after the 2.2 Ga intrusion of widespread gabbro sheets and dykes resulted in the separation of the Archean Superior and Wyoming cratons and their Early Proterozoic covers. These crustal fragments were subsequently reassembled durin

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Dunning, G. R., C. Lepvrier, S. J. O'brien, S. P. Colman-Sadd, and H. Maluski. "Chronology of Avalonian events on Presqu'île du Cap Miquelon (Le Cap), Saint-Pierre et Miquelon (France)." Canadian Journal of Earth Sciences 32, no. 7 (1995): 952–58. http://dx.doi.org/10.1139/e95-080.

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U/Pb geochronology and field studies on Presqu'île du Cap Miquelon demonstrate that amphibolite-grade metamorphism, ductile deformation, and subsequent plutonism in this part of the Appalachian Avalon Zone are of Proterozoic age. Clear, crosscutting relationships between a dated granite dyke (part of the Cap Blanc granite) and foliated, amphibolite-grade metasedimentary and metaigneous rocks provide a younger age limit of [Formula: see text] Ma for tectonism. Proterozoic titanite and hornblende ages indicate that no significant younger thermal overprint occurred such as those recorded in nearb

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29

Frost, Carol D., and B. Ronald Frost. "Proterozoic ferroan feldspathic magmatism." Precambrian Research 228 (May 2013): 151–63. http://dx.doi.org/10.1016/j.precamres.2013.01.016.

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30

VIDAL, GONZALO. "Life in the Proterozoic." Lethaia 28, no. 1 (1995): 84. http://dx.doi.org/10.1111/j.1502-3931.1995.tb01595.x.

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31

Pavlov, Alexander A., Matthew T. Hurtgen, James F. Kasting, and Michael A. Arthur. "Methane-rich Proterozoic atmosphere?" Geology 31, no. 1 (2003): 87. http://dx.doi.org/10.1130/0091-7613(2003)031<0087:mrpa>2.0.co;2.

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32

Rickard, D. "Proterozoic Volcanogenic Mineralization Styles." Geological Society, London, Special Publications 33, no. 1 (1987): 23–35. http://dx.doi.org/10.1144/gsl.sp.1987.033.01.03.

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33

PeiSheng, BAO. "Proterozoic ophiolite and chromite." Acta Petrologica Sinica 35, no. 10 (2019): 2971–88. http://dx.doi.org/10.18654/1000-0569/2019.10.03.

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34

Bozhko, N. A. "Rifting in the Proterozoic." Tectonophysics 143, no. 1-3 (1987): 93–101. http://dx.doi.org/10.1016/0040-1951(87)90081-3.

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35

Kuznetsov, V. G. "Geochemical environments of the Archean-Proterozoic." Доклады Академии наук 488, no. 4 (2019): 403–7. http://dx.doi.org/10.31857/s0869-56524884403-407.

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In the Precambrian section, there is a change of Archean calcite carbonate rocks to magnesia and ferrous in the Proterozoic. This is correlated with the massive development of cyanobacteria, the absorption of which carbon dioxide and the generation of oxygen, led to a change in the acidic reduction conditions of Archaean alkaline oxidizing in the Proterozoic.

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Cohen, Phoebe A., and Francis A. Macdonald. "The Proterozoic Record of Eukaryotes." Paleobiology 41, no. 4 (2015): 610–32. http://dx.doi.org/10.1017/pab.2015.25.

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AbstractProterozoic strata host evidence of global “Snowball Earth” glaciations, large perturbations to the carbon cycle, proposed changes in the redox state of oceans, the diversification of microscopic eukaryotes, and the rise of metazoans. Over the past half century, the number of fossils described from Proterozoic rocks has increased exponentially. These discoveries have occurred alongside an increased understanding of the Proterozoic Earth system and the geological context of fossil occurrences, including improved age constraints. However, the evaluation of relationships between Proterozo

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37

Olson, Stephanie L., Christopher T. Reinhard, and Timothy W. Lyons. "Limited role for methane in the mid-Proterozoic greenhouse." Proceedings of the National Academy of Sciences 113, no. 41 (2016): 11447–52. http://dx.doi.org/10.1073/pnas.1608549113.

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Pervasive anoxia in the subsurface ocean during the Proterozoic may have allowed large fluxes of biogenic CH4to the atmosphere, enhancing the climatic significance of CH4early in Earth’s history. Indeed, the assumption of elevatedpCH4during the Proterozoic underlies most models for both anomalous climatic stasis during the mid-Proterozoic and extreme climate perturbation during the Neoproterozoic; however, the geologic record cannot directly constrain atmospheric CH4levels and attendant radiative forcing. Here, we revisit the role of CH4in Earth’s climate system during Proterozoic time. We use

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38

Kalsbeek, F., P. N. Taylor, and R. T. Pidgeon. "Unreworked Archaean basement and Proterozoic supracrustal rocks from northeastern Disko Bugt, West Greenland: implications for the nature of Proterozoic mobile belts in Greenland." Canadian Journal of Earth Sciences 25, no. 5 (1988): 773–82. http://dx.doi.org/10.1139/e88-072.

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Whole-rock Rb–Sr and Pb–Pb and zircon U–Pb isotope data yield an age of approximately 2800 Ma for the Atâ granite from northeastern Disko Bugt, West Greenland. Field observations and isotope data suggest that the surrounding gneisses were formed by deformation and recrystallization of granitoid rocks similar to the Atâ granite some 100 Ma after the emplacement of the granite. Rb–Sr whole-rock data on siltstones at low metamorphic grade give an age of 1760 ± 185 Ma, which is interpreted as the time of closure of the isotope systems after metamorphism. The initial 87Sr/86Sr ratio demonstrates th

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Hall, Jeremy, Richard J. Wardle, Charles F. Gower, et al. "Proterozoic orogens of the northeastern Canadian Shield: new information from the Lithoprobe ECSOOT crustal reflection seismic survey." Canadian Journal of Earth Sciences 32, no. 8 (1995): 1119–31. http://dx.doi.org/10.1139/e95-093.

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As part of the Eastern Canadian Shield Onshore–Offshore Transect (ECSOOT), Lithoprobe acquired 1250 km of deep seismic reflection data along the coast of Labrador and across Ungava Bay, to image evidence of Proterozoic crustal accretion to the Archean nuclei of the Nain and Superior provinces of the Canadian Shield. The relatively pristine Archean crust of the Nain Province has low reflectivity and generally lacks systematic reflector orientations. Reworking of Archean crust on the margins of the Makkovik Province has little effect on this weak signature. In contrast, the Archean crust in the

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Zamil, M. Sh. "A possible model of the Paleozoic sedimentary basins evolution at the North African platform." Proceedings of higher educational establishments. Geology and Exploration, no. 6 (December 28, 2017): 68–73. http://dx.doi.org/10.32454/0016-7762-2017-6-68-73.

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A dual model of the Paleozoic basins development, disposing on the Late Proterozoic (Pan-African) and the Early Proterozoic (Eburnean) crust, has been proposed. The formation of the first group basins is connected with the subsiding of the sections of the cooling gneissic-domes of«rejuvenated» (Early Precambrian but tectonically reworked at the end of the Proterozoic) Pan-African crust. Accordingly, the development of the second group basins is a result of the Precambrian deep sited (mantle) magmatic chambers cooling and subsiding together with the sites of the old lithosphere, covering them.

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DICKIN, A. P., and G. P. DURANT. "The Blackstones Bank igneous complex: geochemistry and crustal context of a submerged Tertiary igneous centre in the Scottish Hebrides." Geological Magazine 139, no. 2 (2002): 199–207. http://dx.doi.org/10.1017/s0016756802006283.

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The Blackstones Bank, located about 60 km WSW of the Isle of Mull in Western Scotland, is a submarine plutonic complex in the British Tertiary Igneous Province. Geochemical and isotopic analysis of gabbros, microgabbros and basic dykes shows that the magmas interacted strongly with crustal rocks during their emplacement. The isotopic signature of the contaminated Tertiary intrusions shows no evidence of any interaction with Archaean basement, despite the location of the Blackstones complex to the west of the Great Glen fault. Instead, the Blackstones rocks have crustal signatures resembling th

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Indares, Aphrodite, and Toby Rivers. "Textures, metamorphic reactions and thermobarometry of eclogitized metagabbros: a Proterozoic example." European Journal of Mineralogy 7, no. 1 (1995): 43–56. http://dx.doi.org/10.1127/ejm/7/1/0043.

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43

Cook, Frederick A., John L. Varsek, and Elizabeth A. Clark. "Proterozoic craton to basin crustal transition in western Canada and its influence on the evolution of the Cordillera." Canadian Journal of Earth Sciences 28, no. 8 (1991): 1148–58. http://dx.doi.org/10.1139/e91-105.

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Deep seismic reflection data have imaged a crustal-scale, west-facing ramp or ramp system in the subsurface of western Canada. In northwestern Canada the ramp is within Proterozoic crust east of the Cordillera and is unconformably overlain by Paleozoic sedimentary rocks, indicating that it was formed during the Proterozoic in this region. Similar structures are visible within the Cordillera in southern Canada and the northwestern United States along a south projection of the ramp observed in the north. In the Monashee Complex of British Columbia and in the Priest River Complex in northern Wash

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Bluck, B. J., W. Gibbons, and J. K. Ingham. "Terranes." Geological Society, London, Memoirs 13, no. 1 (1992): 1–4. http://dx.doi.org/10.1144/gsl.mem.1992.013.01.03.

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AbstractThe Precambrian and Lower Palaeozoic foundations of the British Isles may be viewed as a series of suspect terranes whose exposed boundaries are prominent fault systems of various kinds, each with an unproven amount of displacement. There are indications that they accreted to their present configuration between late Precambrian and Carboniferous times. From north to south they are as follows.In northwest Scotland the Hebridean terrane (Laurentian craton in the foreland of the Caledonian Orogen) comprises an Archaean and Lower Proterozoic gneissose basement (Lewisian) overlain by an und

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Wu, He Yuan, and Bin Hao. "Third-Order Sequence Division of Yunmengshan and Baicaoping Formation of Proterozoic in Yuxi District of China: an Example from Xiatang Profile in Lushan." Advanced Materials Research 998-999 (July 2014): 1492–97. http://dx.doi.org/10.4028/www.scientific.net/amr.998-999.1492.

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There are controversies on the Proterozoic stratigraphic genesis, division, correlation and palaeogeographical evolution of western Henan in China. Based on the basic description of sedimentary facies, Yunmengshan and Baicaoping formation of Proterozoic typical section in western Henan is divided into 4 third-order sequences. Sequence stratigraphy framework which reflects sedimentary and overlap is established with basis of two kinds of facies-change surface and two kinds of diachrononism in stratigraphical records. Although chronostratigraphic belonging of Precambrian strata is controversial

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Henriksen, N., J. D. Friderichsen, R. A. Strachan, N. J. Soper, and A. K. Higgins. "Caledonian and pre-Caledonian geology of the region between Grandjean Fjord and Bessel Fjord (75°–76°N), North-East Greenland." Rapport Grønlands Geologiske Undersøgelse 145 (December 31, 1989): 90–97. http://dx.doi.org/10.34194/rapggu.v145.8084.

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The area between Grandjean Fjord and Bessel Fjord was the focus in 1988 of regional geological investigations and 1:500000 mapping during the North-East Greenland project (Henriksen, 1989). The greater part of the area forms part of the East Greenland Caledonides and can be divided into three distinct rock groups: infracrustal gneisses and granites of possibie Archaean or early Proterozoic origin; a metasedimentary sequence which has probably suffered both mid-Proterozoic and Caledonian migmatisation and metamorphism; and the late Proterozoic Eleonore Bay Group, a thick sedimentary sequence wh

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Clemmensen, L. B., and H. F. Jepsen. "Lithostratigraphy and geological setting of Upper Proterozoic shoreline-shelf deposits, Hagen Fjord Group, eastern North Greenland." Rapport Grønlands Geologiske Undersøgelse 157 (January 1, 1992): 1–27. http://dx.doi.org/10.34194/rapggu.v157.8195.

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During the Late Proterozoic a more than 1000 m thick succession of sediments was deposited on the shelf fringing the north-eastern corner of the Greenland craton. These sediments were classified together with an underlying turbidite sequence in the Hagen Fjord Group (Haller, 1961), which is here redefined to contain only Upper Proterozoic, mainly shallow marine shelf deposits outcropping between Independence Fjord and Kronprins Christian Land in eastern North Greenland. Both siliciclastic and carbonate sedimentation occurred during the Late Proterozoic, and the changing tectonic environment al

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Escher, J. C., and R. P. Hall. "The Niflheim thrust: a tectonic contact between granulite and amphibolite facies gneisses, South-East Greenland." Rapport Grønlands Geologiske Undersøgelse 146 (December 31, 1989): 66–69. http://dx.doi.org/10.34194/rapggu.v146.8098.

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The Niflheim thrust forms part of the northern boundary zone of the Proterozoic mobile belt of the Ammassalik region and defines the southernmost extent of granulite facies gneisses north-west of Sermilik. The thrust sharply separates grey amphibolite facies gneisses (footwall) from a thick and extensive unit of brown granulite facies gneisses, suggesting considerable lateral as well as vertical transport of the brown gneisses. Above the contact, the brown gneisses have only been weakly affected by deformation, whilst below the contact intensely folded and sheared grey gneisses indicate strong

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BARTLEY, JULIE K., MICHAEL POPE, ANDREW H. KNOLL, MIKHAIL A. SEMIKHATOV, and PETER YU PETROV. "A Vendian–Cambrian boundary succession from the northwestern margin of the Siberian Platform: stratigraphy, palaeontology, chemostratigraphy and correlation." Geological Magazine 135, no. 4 (1998): 473–94. http://dx.doi.org/10.1017/s0016756898008772.

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Siberia contains several key reference sections for studies of biological and environmental evolution across the Proterozoic–Phanerozoic transition. The Platonovskaya Formation, exposed in the Turukhansk region of western Siberia, is an uppermost Proterozoic to Cambrian succession whose trace and body fossils place broad limits on the age of deposition, but do not permit detailed correlation with boundary successions elsewhere. In contrast, a striking negative carbon isotopic excursion in the lower part of the Platonovskaya Formation permits precise chemostratigraphic correlation with uppermos

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Zhang, Huimin. "Preliminary Proterozoic apparent polar wander paths for the South China Block and their tectonic implications." Canadian Journal of Earth Sciences 35, no. 3 (1998): 302–20. http://dx.doi.org/10.1139/e97-117.

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Results of a regional paleomagnetic study of Precambrian rocks in central-east China are summarized and interpreted. The study is a partial outcome of a geoscience transect incorporating three terranes, namely the Yangzi, Jiangnan, and Huaxia blocks. Paleomagnetic poles derived from a range of metamorphic, igneous, and sedimentary rocks define a northeast to southwest swath crossing the present Pacific Ocean and interpreted to embrace Early to Late Proterozoic times. All three terranes define segments of the same swath and correlate with a similar apparent polar wander path previously defined

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