Givetian Deepwater Sediments in the Western Slope of the Subpolar Urals

摘要

In 1996, the author of the present paper first described and sampled macro- and microfossils in the Givetian section of deepwater sediments in the Subpolar Urals. The section outcrops in exposure 86 on the left bank of the Bol'shaya Nadota River near the western foothill of Mt. Olysya. The Givetian sediments are confined to the tectonically complicated area sandwiched between the Elets and Lemva facies that are characterized by wide development of reverse faults and thrusts (Fig. 1). The section (total thickness ～50 m) is largely composed of shales and their phyllite-type varieties with limestone lenses. In the lower part of the section, shales enclose a limestone member (Fig. 2). The entire rock sequence shows a normal succession with beds dipping to east-northeast at an angle of 30°. In the upstream part of the outcrop, shales at the top of the member have tectonic contact with upper Visean limestones that dip to northeast at an angle of 45°.