APPLICTION OF GRAVITY-SEISMIC INVERSION IN PETROLEUM RESOURCES EVALUATION OF THE LABUDALIN BASIN

The Labudalin basin in Inner Mongolia covers a large area, yet with a low degree of exploration for oil and gas. Due to the poor seismic imaging for deep strata by the strong reflection shielding effect of widely distributed volcanic rocks in the shallow, it is difficult to evaluate the exploration potential of oil and gas in the basin. In order to recognize the distribution of sedimentary rocks and the bottom depth of the Shangkuli Formation of the target strata in the basin, gravity-seismic inversion interpretation of two-dimensional seismic data is carried out in the south of the basin. The gravity and magnetic model is established with embedding seismic profiles in simulated GM-SYS gravity and magnetic software. The gravity interference of overlying volcanic rocks is eliminated by using the reliable interpretation results of shallow seismic strata as constraints. The multiplicity of deep structural interface in gravity inversion is reduced, and the bottom depth and sedimentary rock thickness of the Shangkuli Formation are successfully inverted. On this basis, the petroleum prospects of the basin are estimated and the Bayanhada fault depression is delineated as a favorable exploration area.