Results 161 to 170 of about 5,124,862 (215)

Biostratigraphy of the Vendian-Cambrian beds and the lower Cambrian boundary in Siberia

Geological Magazine, 1993
AbstractGeneral agreement exists that the position of the base of the Cambrian (Precambrian–Cambrian boundary) should coincide with a biostratigraphic marker that can be widely traced and is linked to the evolution of the small shelly fauna. On the Siberian platform the presence of distinct facies during the Vendian–Cambrian interval has made ...
V. V. Khomentovsky, G. A. Karlova
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A Possible Lower Cambrian Chaetognath (Arrow Worm)

Science, 2002
The phylum Chaetognatha (also called arrow worm), with only about 100 living species, is found in oceans throughout the world and plays an important role in the food web as primary predators ([1][1]). Its fossil record, however, is sparse. The Carboniferous Paucijaculum samamithion has been the only definitive fossil chaetognath ([2][2]).
Jun-Yuan, Chen, Di-Ying, Huang
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A comparative study of Lower Cambrian Halkieria and Middle Cambrian Wiwaxia

Lethaia, 1984
Two Cambrian lepidote metazoans known from different respective types of preservation have been compared in order to elucidate their biology and affinities. The widely distributed Lower Cambrian Halkieria is represented by isolated hollow sclerites, probably of originally calcareous composition.
Stefan Bengtson, Simon Conway Morris
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The Cambrian Lower Boundary Problem

Geological Magazine, 1967
ABSTRACTBased on the study of distribution of assemblages of skeletal organic remains we have established the synchronous appearance of a skeleton in certain fossil groups; this enables us to draw the lower boundary of Cambrian according to the first zone with a certain assemblage of skeletal fossils.Wide distribution, in sections of various parts of ...
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THE LOWER CAMBRIAN FOSSIL TOMMOTIA

Lethaia, 1970
The genera Tommotia Missarzevskij 1970 (1966) and Camenella Missarzevskij 1966 from the Lower Cambrian Tommotian Stage of the Siberian Platform represent different skeletal parts of the same organism and are consequently synonymous. Tommotia is selected as the valid name. Tommotia baltica n.sp.
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Lower Cambrian Olenellus zone of the Appalachians

Geological Society of America Bulletin, 1938
INTRODUCTION Lower Cambrian fossils were first discovered by Emmons in eastern New York almost a century ago. Since then, many specimens have been obtained from the Appalachian region, but the stratigraphy received little attention. Recently, interest in the study of the early Paleozoic rocks of the Appalachians has revived. A. F.
C. E. RESSER, B. F. HOWELL
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Problematic Porifera from the Lower Cambrian of Western Mongolia

Paleontological Journal, 2023
From the lower part of the Tommotian Stage of the Lower Cambrian of Western Mongolia, ridge Hevte-Tsakhir-Nuruu described a new species of problematical microfossils of the genus Aetholicopalla Conway Morris in Bengtson et al., 1990, whose representatives are sometimes the dominants of the Early Cambrian taphocoenoses. A. grandipora sp.
E. A. Luzhnaya, E. A. Zhegallo, L. V. Zaitseva, A. L. Ragozina   +3 more
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To the problem of stage subdivision of the Lower Cambrian

Stratigraphy and Geological Correlation, 2008
It was a serious mistake when subdivision stratotypes had been disposed of in practice of constructing the General stratigraphic scale, because they cannot be substituted by the boundary stratotypes. A subdivision stratotype and respective GSSP are complementary parts characterizing any stratigraphic unit.
A. Yu. Rozanov, V. V. Khomentovsky, Yu. Ya. Shabanov, G. A. Karlova, A. I. Varlamov, V. A. Luchinina, T. V. Pegel’, Yu. E. Demidenko, P. Yu. Parkhaev, I. V. Korovnikov, N. A. Skorlotova   +10 more
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Lower Cambrian of Southeastern Newfoundland

1992
The Avalon Zone in the coastal northeastern Appalachian Mountains, in Wales, and in central England preserves a particularly significant record of the evolutionary radiations, immigration history, and provincialism of latest Precambrian and Early Cambrian metazoans.
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LOWER CAMBRIAN IRON QUARTZITES OF TUVA

International Geology Review, 1962
A bed of banded quartzite rich in magnetite, between six and seven meters thick and one kilometer along the strike, is reported from the Kara Beldyr region of southeast Tuva. It is dated Lower Cambrian on the basis of Epiphyton and archeocyathids in associated limestones. — M. Russell.
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