Geological and geochemical study of the paint in Tuha Basin

Abstract

 This paper proposes that the primary geological and geochemical conditions for coal-generated oil and gas are favorable coal phases for oil generation - flowing water swamp phases. The early hydrocarbon-generating components (matrix vitrinite, suberinite and resin body, etc.) rich in coal begin to generate hydrocarbons when the R value is 0.35%, reach a peak at 0.6%, and end at 0.7% to 0.8%; calculations show that the adsorption threshold of micropores in coal for hydrocarbons is 86 mg/g, and hydrocarbons must be greater than this value before coal-generated hydrocarbons are discharged; through the study of coal pore distribution and its adsorption of hydrocarbons, it is shown that the most favorable period for coal-generated hydrocarbons to be expelled is before R value is 0.8%; early structures, oil source faults and regional caprocks are necessary conditions for the formation of coal-generated oil reservoirs.