Biostratigraphy

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biostratigraphy

[¦bī·ō·strə′tig·rə·fē]
(paleontology)
A part of paleontology concerned with the study of the conditions and deposition order of sedimentary rocks.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Biostratigraphy

 

a branch of stratigraphy which studies the distribution of fossil remains of organisms in sedimentary deposits with the object of determining the relative age and the correlations between layers of the same age in different territories. The task of biostratigraphy is the elaboration of scales of the relative age of layers (in various degrees of detail and of various scopes, but in zonal layers in particular). The succession of biostratigraphic zones reflects the change in geological cross section of fossil remains from a group of extinct organisms of different taxonomic classes or their systems. Of special importance in the differentiation of zones, and above all of biozones, are groups of extinct organisms that had relatively short life-spans but that attained widespread distribution, significant abundance, and variety (for example, nummulites, graptolites, and dinosaurs). Zones are frequently based on stages in the evolution of certain rapidly changing groups of extinct organisms (for example, corals of the subclass Rugosa). The study of the remains of ancient microscopic organisms (micropaleontology), the quantity of which can be extremely large even in small specimens (for example, from deep chinks), is important for the goals of biostratigraphy. Remnants of planktonic organisms (foraminifers, algae, and others) that were carried for great distances by currents allow zones of great territorial expanse to be distinguished. Fossil remains of plant spores and pollen, which were carried for great distances by the wind, are important for correlating deposits of maritime or continental origin that are of the same age. Biostratigraphy makes broad use of the methods of paleoecology for reconstructing the conditions under which ancient organisms existed in order to distinguish complexes of organisms of the same age living in different conditions from complexes of organism of different ages living in similar conditions.

REFERENCES

Menner, V. V. “Biostratigraficheskie osnovy sopostavleniia morskikh, lagunnykh i kontinental’nykh svit.” Tr. geologicheskogo instituta AN SSSR, 1962, issue 65.
Stratigraficheskaia klassifikalsiia, terminologiia i nomenklatura. Leningrad, 1965.
Stepanov, D. L. Printsipy i metody biostratigraficheskikh issledovanii. Leningrad, 1958.

R. L. MERKLIN

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
The dendrograms generated from the Estonian and Belarus brachiopod data (Figs 4, 6) indicate that the uppermost units of the Viru Series (Vinni Subseries; Oandu and Rakvere RSs) are aligned biostratigraphically more closely with the units of the Harju Series.
Menabites (Bererella) walnutensis & Glyptoxoceras aguisgranense) that correlates biostratigraphically with Texas and Northern Europe (Kennedy et al., 1997), and 3) the complete lack of vertebrate material.
Presence of all these biostratigraphically significant shallow benthic foraminifera confirms that the deposition of Margalla Hill Limestone and Chorgali Formation occurred in Shallow Benthic Zones (SBZ 5/6 - SBZ12) of Ypresian time.
The main faunal renovation among biostratigraphically important microfossils occurs on the lower boundary of this member (e.g.
2010); more detailed dates are not possible given the lack of biostratigraphically useful fossils.
Despite its very limited distribution, the Orascja Member, with specific alternation of muddy and sandy lithologies and sufficiently rich assemblages of biostratigraphically valuable conodonts and several dendroid graptolites, is a significant unit for understanding the geological history of the area.
Regional correlation of subsurface units of the "Siluro-Devonian" of the Permian Basin region of West Texas and southeastern New Mexico has been hindered by a lack of published data on biostratigraphically useful fossils.
However, the trackway shows characters diagnostic only at the level of Tetrapoda and thus is not biostratigraphically useful.
As a result from the ramp morphology and controlled by regional tectonics and sea level changes, the thickness of these units increases towards the west, which are biostratigraphically well constrained due to the abundance of benthic and nektonic fauna, namely ammonites and calcareous nannofossils (Silva et al., 2011; Duarte et al., 2010; Oliveira et al., 2007; Dommergues and Mouterde, 1987; Mouterde, 1953, 1967) (Fig.