Results 161 to 170 of about 3,951 (214)

Riphean and Vendian of the USSR

Precambrian Research, 1981
Abstract The Upper Proterozoic of the U.S.S.R. is subdivided into two chronostratigraphic units according to the officially-adopted stratigraphic scale: the Riphean, 1650 ± 50−650 ± Ma, comprising four subordinate subdivisions; and the Vendian, 650 ± Ma—Cambrian.
N.M. Chumakov, M.A. Semikhatov
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Late Precambrian Dolomites, Vendian Glaciation, and Synchroneity of Vendian Glaciations: A Discussion

The Journal of Geology, 1977
Am. Jour. Sci., v. 274, p. 673-824. ---1974b, No evidence for glacial origin of late Precambrian tilloids in Angola: Nature, v. 252, p. 114-116. ---1975, Tectonic framework of Late Precambrian supposed glacials, in WRIGHT, A. E., and MOSELEY, F., eds., Ice Ages: Ancient and Modern: Geol. Jour., special issue No. 6, p. 241-274. ---1976a, Reply: Am. Jour.
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Late Precambrian Dolomites, Vendian Glaciation, and Synchroneity of Vendian Glaciations

The Journal of Geology, 1976
The late Precambrian Vendian Glaciation may have been triggered by a worldwide fall of temperature following the locking up of carbon dioxide in Upper Riphean Dolomites. In this "anti-greenhouse" mechanism, the Vendian case appears to differ from Gondwana and Pleistocene events which are restricted to the poles and not worldwide in extent.
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Global climates of the Vendian

Russian Journal of Earth Sciences, 2003
The global climate of the Vendian has been the subject of considerable debate. In view of the diculties of stratigraphic correlations, the absence of reliably reconstructed positions of continents, the scarcity of climate indicators, and the fact that Vendian outcrop areas are widely separated, it is so far possible to identify only the most general ...
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Metameric features in the Vendian metazoans

Italian Journal of Zoology, 1998
Abstract Metamerism as the serial homology is widespread among the Vendian (Late Precambrian) metazoans. Prevalence of segmented forms among the Vendian Bilateria suggests that in many phylogenetic lineages of Metazoa the evolutionary development of the bilateral symmetry and metamerism were related processes.
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Paleoecological feedback and the Vendian-Cambrian transition

Trends in Ecology & Evolution, 1988
The emergence of abundant skeletonized animals during the Vendian-Cambrian transition is seen by paleontologists as an 'explosion' when nearly all basic designs of invertebrate life appeared for the first time in the fossil record. Breakthroughs in trophic strategy, involving an increasing three-dimensionality in the benthic habitat and positive ...
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YUDOMIAN (VENDIAN) OF THE TYPE LOCALITY

Russian Geology and Geophysics, 1994
With new data obtained, the Yudomian Series (the Siberian Vendian) is characterized more precisely and more comprehensively in its type locality (Bol. Aim R. basin and near the Yudoma R. mouth). The new data corroborate the Tommotian age of the most ancient layers of the Pestrotsvet Formation in the region, which overlap here the Yudomian deposits with
V. V. Khomentovsky, G. A. Karlova
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Was Scotland a Vendian RRR junction?

Journal of the Geological Society, 1994
In Early Palaeozoic time northern Scotland occupied a 120° promontory between the Appalachian and Greenland Iapetus-facing margins of Laurentia. It is proposed that this originated at a triple rift (RRR) jundion between Laurentia and two other continents, possibly Baltica and West Gondwana.
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Chapter 12 Pre-Vendian history

Geological Society, London, Memoirs, 1997
It so happens that rocks of Vendian age are extensive and are well exposed in Svalbard. This applies especially to early Vendian, i.e. Varanger, with two distinctive glacial horizons as are treated in the Chapter 13. The Early Varanger (Smalfjord) episode can be correlated in most sections and so provides a reference horizon which serves approximately ...
W. Brian Harland, Nicholas J. Butterfield   +1 more
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Chapter 13 Vendian History

Geological Society, London, Memoirs, 1997
The Vendian Period, the latest Precambrian division, and the earliest division in which several Phanerozoic methods of correlation can be applied, is a convenient time division for Svalbard. It is separated from the earlier history in which correlation has uncertainties of tens of millions of years if not more.
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