Geology of carbonaceous deposits of the Birgilda strata (East Ural Trough)

Abstract

The article describes the geological structure of the Birgilda strata, which is widely developed in the East Ural trough. It is shown that the Birgilda black shales, which contain Corg in the range of 0.5-2.7% (average 1.3%), are of the low-carbon type. The exothermic effect in them occurred mainly in the temperature range 570-660 ° С, which corresponds to the greenschist facies of regional metamorphism. On the A-S-C diagram, the rocks of the Birgilda strata are approximately equally scattered over the carbonate-carbonaceous and siliceous-carbonaceous fields and noticeably less in the terrigenous-carbonaceous fields. The Birgilda sequence is characterized by a collisional environment of accumulation and products of destruction of mainly basic igneous rocks.