Abstract:

A method of gravity inversion was promoted with IGGM gravitational and aeromagnetic data.A combined gravity-seismic inversion was applied to Yingcheng-Jianli section, Jianghan basin, and the structure frame in the study area was recognized The results are consistent between the calculation and the fact, and 3 new faults are speculated. The conclusion is drawn that two small density strata of J-T₂ and S separate big others to form a sandwich phenomenon, and that the velocity data and densities of strata regularly change between bigness and smallness. The indicator of geologic structures is also analyzed from the gravitational and aeromagnetic characteristics. The relationship among the faults, drapes, the force and tectonic movement is also discussed. It is revealed that the Himalayan movement is of great importance to the basin reformation and to the hydrocarbon accumulation.

Key words: combined gravity-seismic inversion, gravity anomaly, Jianghan basin, IGGM