Arenig Stage

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 It might be outdated or ideologically biased.

Arenig Stage

 

(named for Mount Arenig in Wales), the second stage from the bottom in the Ordovician system. Graptolites (Expansograptus extensus, E. hirundo), trilobites, and brachiopods are characteristic marine deposits of the Arenig stage. It occurs in the USSR (Kazakhstan and Siberia), Western Europe, non-Soviet Asia, Australia, and North America.

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