Deep hydrocarbon genesis and accumulation model of strike-slip fault reservoirs in the Yuemanxi area of the Tarim Basin.

As a clean and environmentally friendly energy source, deep oil and gas has always been the focus of the oil and gas industry. The study of hydrocarbon accumulation in deep strike-slip fault zones is a challenging and important area of research in the oil and gas industry. In particular, accurately modeling oil and gas accumulation in the Yuemenxi area of the Tarim Basin presents significant difficulties due to the varying physical properties and gas composition of the Ordovician reservoirs, as well as the complex origin of oil and gas in the area. However, by calculating biomarker parameter maturity on oil samples from strike-slip faults, researchers have discovered that the light oil in the area is sourced from high maturity source rocks in the Later Caledonian, with vitrinite reflectance ranging from 0.79% to 1.11%. The complete distribution of n-alkanes and high concentration of low-carbon n-alkanes in the crude oil suggest that the fluid in the reservoir has not undergone any secondary alteration since its initial accumulation. The carbon isotope and component ratio analysis of natural gas in the Yuemanxi area indicates that the Ordovician natural gas is predominantly kerogen cracking gas. Comprehensive hydrocarbon genesis and accumulation conditions, this paper presents a differential accumulation model for the Ordovician reservoirs in the region, which were controlled by strike-slip faults and source rocks. Based on these findings, it can be inferred that there is significant potential for oil and gas exploration and development in the deeper layers of these strike-slip fault zones. • The paper presents a differential model for the accumulation of oil & gas. • The Ordovician crude oil was sourced from highly mature Late Caledonian source rocks. • The Ordovician natural gas is mainly composed of gas generated by kerogen degradation. • The Ordovician crude oil didn't experience secondary alteration after accumulation. [ABSTRACT FROM AUTHOR]