Results 161 to 170 of about 2,604 (197)

THE STRATIGRAPHY OF THE UPPER PRECAMBRIAN AND LOWER CAMBRIAN IN SOUTH-EASTERN TUVA AND NORTHERN MONGOLIA

Russian Geology and Geophysics, 1992
A new stratigraphic scheme of the Upper Precambrian – Lower Cambrian in South-Eastern Tuva and Northern Mongolia is the result of lengthy integral investigations. Three regional subdivisions are discussed. These are Sangilen, Khugein (Upper Riphean) and Eastern Tuva (Vendian – Lower Cambrian) horizons enclosing lateral rows of local formations.
A. S. Gibsher, A. A. Terleev
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Strontium isotopic evidence relating to the evolution of the lower Precambrian granitic crust in Swaziland

Geology, 1976
Isotopic data for Swaziland Precambrian gneissic rocks, with Rb-Sr whole-rock ages in the range from 3,400 to 3,100 m.y., lie on a steep initial 87 Sr/ 86 Sr ratio versus time development line that intersects the basalt development line (or region) at about 3500 m.y. B.P.
R. D. Davies, H. L. Allsopp
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Acritarchs from the Bohemian Precambrian (Upper Proterozoic) and Lower-Middle Cambrian

Review of Palaeobotany and Palynology, 1974
Abstract Acritarchs and other microfossils from the Bohemian Upper Proterozoic are briefly discussed together with an evaluation of their stratigraphic value in the Precambrian rock sequences. It is shown that part of the presumed Upper Proterozoic in Bohemia could well belong to the Lower Paleozoic (Cambrian).
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GEOCHEMISTRY OF THE UPPER PRECAMBRIAN AND LOWER CAMBRIAN BLACK SHALES FROM THE PHJONNAM DEPRESSION

Russian Geology and Geophysics, 1991
Thirty two samples from the Upper Precambrian and Lower Cambrian deposits of the Phjonnam depression, Sino-Korean Shield, have been analyzed for 43 chemical elements by X-ray fluorescence, atomic-absorption and instrumental neutron-activation methods. Organic carbon in black shales was established to be accompanied by the same elements as in sapropelic
V. M. Gavshin, N. A. Sozinov
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Origin of the Antietam Formation (late Precambrian?; lower Cambrian), central Virginia

Journal of Sedimentary Research, 1970
Abstract Quartz-rich clastics, derived from low-lying complex of crystalline rocks and sediments to the west in the craton, paleocurrent analysis, current reworking insignificant, no southeast borderland ...
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Time, space and intensity relationships of the Precambrian and lower Palaeozoic metamorphisms of the Scottish Highlands

Geological Society, London, Special Publications, 1979
Summary Isotopic evidence suggests that a complex sequence of events, collectively known to us as the Morarian event, affected the Morar and Glenfinnan divisions of the Moine from 1000 to 750 Ma. A regional thermal anticline, with a minimum age of 750 Ma, extends north from Ardgour to northern Ross-shire: it probably extends southwards under ...
R. St J. Lambert, J. A. Winchester, J. G. Holland   +2 more
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Nature and classification of microfossils of plant origin from Precambrian and lower Paleozoic

International Geology Review, 1965
A general consolidation of data relating to reports of Precambrian and lower Paleozoic spores of land plants and hystrichosphaers is presented. Emphasis is placed on the necessity of establishing clear and objective means of separating and classifying these organic remains. Their value lies in the theoretical interpretation of the origin of land plants
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Stratigraphy and Correlation of Basal Sections of the Lower Precambrian of the Southern Part of the Siberian Craton

Stratigraphy and Geological Correlation
For the southern part of the Siberian Craton, the geological and geochronological characteristics of the reference sections of six stratoregions of the Lower Precambrian are given. For the first time, their correlation was carried out, which served as the basis for the refined author’s regional stratigraphic scheme of the region.
Yu. B. Bogdanov, S. A. Anisimova
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Precambrian and Lower Ordovician rocks in east-central Idaho

Professional Paper, 1975
Edward Thompson Ruppel, R. J. Ross, David Schleicher   +2 more
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Amphibolitic rocks of the lower precambrian matamorphic complex of the Pelagonian massif

2002
Amphibolitic rocks have been found near Stavica in the central part of the Pelagonian massif. They are made up of hornblende, garnet, diopside, epidode, zoisite, albite-oligoclase, biotite as well as titanite muscovite and quartz as accessory minerals.
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