FORMATION OF THE SEDIMENTARY COVER OF THE SOUTH KARA BASIN

Abstract

A scheme of formation of the sedimentary blanket of the South Kara basin is considered, which can further be used for numerical reconstruction of its thermal history. The scheme is based on our analysis of the literature information on the structure and geological history of the Barents-Kara region. This information included an interpreted seismic profile crossing the studied area, drilling data from four wells located along the profile (the University, Rusanov, Leningrad and Kharasavey ones), measurements of the heat flow and deep temperatures in the basin. The proposed scheme considers the formation of the basin as a series of sedimentation stages with various combinations of clay shales, siltstones and sandstones and sedimentation in the Cretaceous and Paleogene with their subsequent erosion in the Miocene. The erosion amplitude is estimated by the observed change in the porosity of sedimentary rocks with depth. The initial heat flow in such a model should correspond to the flow of modern axial zones of continental rifting or be lower for the areas remote from the corresponding segments of the Late Permian-Early Triassic continental rifting system.