TO THE LOWER DEVONIAN BIOSTRATIGRAPHY IN THE RUSSIAN FAR EAST AND MONGOLIA

Abstract

Recent data on the Lower Devonian biostratigraphy in the studied regions are generalized. The described terrigenous and carbonate reference sections yield sharply different faunal assemblages. Carbonate sections of Mongolia, which yield conodont index species of the standard zonation, are correlated with the general stratigraphic scheme of the Devonian. Terrigenous sequences of the Far East and Mongolia are subdivided into regional brachiopod zones of identical stratigraphic succession. The regional zones are calibrated versus the standard Devonian zonations based on their correlation with the carbonate sections.