Tremadoc Stage

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 It might be outdated or ideologically biased.

Tremadoc Stage

 

the lowermost stage of the Ordovician system. It was identified in 1847 by the British geologist A. Sedgwick in Wales, Great Britain. In its type locality at the village of Tremadoc, it is represented by dark slates. The most important fossils of the stage are trilobites (Euloma and Niobe) and graptolites (Dictyonema and Anisograptidae). In the USSR the Tremadoc has been identified in the northwestern part of the Eastern European Platform, in the Southern Urals, in Kazakhstan, and on the Siberian Platform.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Thus the lower portion of the Leetse Formation belongs to the Tremadoc Stage, and to the Hunneberg Regional Stage.
DOS is a formation of the Tremadoc stage (Pakerord and Varangu regional stages) of the Early Ordovician.