Visean palaeoincisions as centers of fluid-generation in the Kama coal basin

Abstract

The paper considers palaeoincisions in the Turnean limestones of the Volga-Ural basin, made by alluvial-deluvial sediments of the Visean age and containing interlayers of coals. Processes occurring in these sediments (catagenic reduction of thickness of coal beds and coal-bearing mudstones, aggressive influence of products of defluidization of coal organic matter on the host rocks, etc.) strengthen the fluid dynamic heterogeneity of intracrustal deposits and contribute to emigration of hydrocarbons (HC). The main oil-and-gas-generating strata in the Carboniferous section include rocks of the Tournaisian stage and the Bobrikovsky horizon of the Viseian stage. Palaeoincisions, along with the area distribution of Viseian coals, can be considered as centers of fluid generation, including liquid and gas HC.

Keywords

• palaeoincisions
• lower carboniferous
• visean stage
• coals
• carbonaceous argillites
• organic matter
• fluid-generation