New Data on the Stratigraphy of the Ordovician and Silurian of the Central Region of Kotelnyi Island (New Siberian Islands) and Correlation with the Synchronous Successions of the Eastern Arctic

摘要

Much of the material of Paleozoic successions of Kotelnyi Island (New Siberian Islands) is composed of various carbonates, which accumulated in relatively shallow conditions in the Ordovician-Middle Devonian. Such deposits are widespread in synchronous sections throughout the Eastern Arctic and therefore attract attention as a potential tool for interregional correlations. In paleotectonic reconstructions, Kotelnyi Island either is included in terrain which was disconnected from the Siberian Platform in the Paleozoic or is joined to it. These different interpretations result from lack of primary evidence. This paper presents new data on stratigraphy and macro- and microfauna of the Upper Ordovician and Silurian of the central regions of Kotelnyi Island. For this interval, we propose a correlation of the studied sections with those of adjacent regions. A conclusion is drawn on the basis of the similarity of lithology and fossil assemblages and also shared trends in the evolution of the sedimentary environment that the Upper Ordovician-Silurian beds of Kotelnyi Island, Taimyr, and the Siberian Platform accumulated in a single shelf basin, which apparently also extends to northeastern Chukotka.