Influence of the tectonic factor on the oil and gas efficiency of the Visean terrigenous complex of the Timan-Pechora province

The influence of gas-fluid processes on the formation of both the rocks of the Visean terrigenous oil and gas bearing complex of the Timan-Pechora province and hydrocarbon deposits in them is considered. It was established that siderite concretions of the Lower Carboniferous terrigenous strata are siderite bacteriolites formed in the back-arc basin with normal marine fauna and occurrence of gas-fluid seepage in the bottom sediment. The formation of pyrophyllite in terrigenous rocks of the eastern margin of the sedimentation basin can also be associated with post-volcanic hydrothermal or metasomatic processes.