Eonothem

eonothem

[′ēn·ə‚them]
(geology)
A chronostratigraphic unit, above erathem, composed of rocks formed during an eon of geologic time.
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 It might be outdated or ideologically biased.

Eonothem

 

(geology), the largest subdivision of the general stratigraphic scale, corresponding to a long stage in the development of the earth and its organic world. An example is the Phanerozoic eonothem, which includes three erathems (groups), consisting of 12 stratigraphic systems. (SeeSTRATIGRAPHY.)

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