The Permian of the Verkhoyansk–Okhotsk region, NE Russia

Abstract

This report summarizes data on the Permian deposits of the Verkhoyansk–Okhotsk region (tectonics, paleogeography, fauna, flora and stratigraphy). The Verkhoyansk–Okhotsk region covers the area of the Verkhoyansk fold-and-thrust belt. The Permian deposits of this region were formed on the passive continental margin of the Angarida Continent, the ancient Siberian Continent, situated within the Siberian Platform. This continental margin developed as the result of continental break-up in the Late Precambrian. Late Precambrian to Jurassic (including Permian) sediments were deposited on a passive margin with a continental shelf extending out into an ocean towards the northeast. During the Permian, exclusively terrigenous sediments were deposited over a vast territory in the Verkhoyansk paleobasin forming part of this continental margin. The Permian deposits are divided into six regional stratigraphic units ranked as horizons (=regional stages), which in turn are subdivided into faunal zones and beds serving as the basis for intra-regional correlation. In the Late Jurassic–Cretaceous the continental margin sediments were converted into a foreland fold-and-thrust belt due to the collision of the Siberian Platform with the Kolyma–Omolon and Okhotsk continental blocks.