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Neoproterozoic magmatism in eastern Himalayan terrane
Science Bulletin, 2017Geochronological investigation on gneisses of granitic to leucogranitic compositions in Cuona, south Tibet, reveal that their protoliths formed at 808.8±7.9-816.4±3.4Ma and 855.8±7.0Ma, respectively. Zircon rims from the granitic gneiss record a metamorphic age of 739.4±4.3Ma.
Yuhua, Wang +7 more
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Neoproterozoic-Cambrian microbialite record
The Paleontological Society Papers, 2004Microbes and the sedimentary record of their activity, microbialites, have existed since the Archaean. During the Neoproterozoic-Cambrian interval, there is a marked shift in the fossil record of microbialites with the widespread proliferation of thrombolites (clotted microbialites) and the appearance and proliferation of dendrolites (microbialites ...
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Neoproterozoic—Cambrian Biological Revolutions
The Paleontological Society Papers, 2004The Neoproterozoic—Cambrian biological and geological events between 630 to 530 or so million years ago, are among the most fascinating topics in life history today because the first animals appeared and radiated amidst environmental changes of major magnitude.
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Neoproterozoic granitoids on Wrangel Island
Doklady Earth Sciences, 2016Based on geochronological U–Pb studies, the age of Wrangel Island granitoids was estimated as Neoproterozoic (Cryogenian). Some granitoids contain zircons with inherited cores with an estimated age of 1010, 1170, 1200, and >2600 Ma, assuming the presence of ancient (Neoarchean–Mesoproterozoic) rocks in the Wrangel Island foundation and their ...
M. V. Luchitskaya +3 more
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The Neoproterozoic glacial broom
GeologyAbstract Neoproterozoic snowball Earth events reflect globally frigid conditions thought to have stimulated changes in geochemical cycling with planetary biotic response. We investigated the impact of these events on sediment dynamics, focusing on the detrital zircon record within the Dalradian Supergroup of Scotland and Ireland ...
C.L. Kirkland +3 more
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The Neoproterozoic supercontinent Palaeopangaea
Gondwana Research, 2007Abstract The Rodinia hypothesis for the Neoproterozoic Supercontinent reconstruction is associated with five major problems: (i) The palaeomagnetic test requires continental break-up hundreds of millions of years before the geological evidence for this event is recognised near the dawn of the Cambrian.
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Two or four Neoproterozoic glaciations?
Geology, 1998A thick Neoproterozoic carbonate and glaciogenic succession of the southern Congo craton has yielded δ 13 C and 87 Sr/ 86 Sr records through the later Cryogenian (ca. 750–600 Ma) and earlier part of the Terminal Proterozoic (ca. 600–570 Ma). Sizeable negative δ 13 C excursions (to less than–5‰) occur above each of two glacial intervals and the 87 Sr/
Martin J. Kennedy +4 more
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Neoproterozoic banded iron formations
Lithology and Mineral Resources, 2009Two epochs of the formation of ferruginous quartzites—Archean-Paleoproterozoic (3.2–1.8 Ga) and Neoproterozoic (0.85–0.7 Ga)—are distinguished in the Precambrian. They are incommensurable in scale: the Paleoproterozoic Kursk Group of the Kursk Magnetic Anomaly (KMA) extends over 1500 km, whereas the extension of Neoproterozoic banded iron formations ...
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Neoproterozoic Laurentia-Australia fit
Geology, 1993The proposed Vendian juxtaposition of western North America and eastern Australia can be tested by comparing sequences on each margin that developed during the major glacial epochs of the Neoproterozoic. The actual fitting of the margins, however, is more difficult, because both margins have been deformed since separation.
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