Stage, Geological

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Stage, Geological

 

a subdivision of the general stratigraphic scale, subordinate to a geological series. A stage is subdivided into stratigraphic zones. It includes the stratum of rocks that formed in one geological age and corresponds to a definite phase in the geological development of the earth. The chief criterion for the establishment of the size and boundaries of a stage is the findings of biostratigraphic analysis. Most stages identified on the basis of open marine basins correspond to terrestrial subdivisions.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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