Abstract: Plate Tectonic Model of the Sedimentary Basins of Northeastern Russia

Alexander Heiphetz, William Harbert

Sedimentary basins of northeastern Russia that have known or potential hydrocarbon accumulations can be separated into two main groups on the basis of their position. Basins of the first group, such as the Anadyrsky and Khatyrsky basins, originated on the boundaries between tectonostratigraphic terranes during the last stages of their accretion to the continental margin in the Paleocene to Miocene. Marine molasse deposits make up the lowermost sediments of these basins. Continental shelf and lacustrine sediments dominate the upper part of the basin-filling sediment sequences. Source rocks may consist of Upper Cretaceous to lower Paleocene shales associated with the basin basement and/or the lowermost parts of the sedimentary fill. Mobilization of the organics and origin of hydrocarbon are due to the recent stages of overthrusting of these basins by the adjacent terranes. Basins of the second group, such as the Il'pinksy, Parapol'sky, and Pustoretsky basins were formed in response to extension. They are filled with lacustrine, deltaic and shallow-water marine sediments. Composition of hydrocarbons and their structural occurrence suggest external, with respect to the basins, origin. Our model includes a connection between rifting and extension in the Penzhina Bay and thrusting in the Anadyrsky and Khatyrsky basins and describes the formation and thermal history of both groups of sedimentary basins.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994