Application of Prestack Inversion to Prediction of Hydrocarbon Potential of Turbidite Sand Bodies in Jinzhou 31-6 Block

In the Liaozhong sag, there is a distal turbidite depositional system in Dongying-2 Member of Jingzhou31-6 Block, where turbidite sand bodies developed in the east and west. It shows vermicular reflection configuration in the seismic profile. As there is little difference of p-wave impedance between sand and shale, between gas sand and wet sand in the poststack inversion profile, reservoir prediction and hydrocarbon detection are very difficult in this area. In this paper, on the basis of rock physics analysis, we adopt prestack AVO simultaneous inversion method to invert the JZ31-6 block prestack 3D seismic data with about 165km2. Then, we crossplot the density and shear modular from inversion result to distinguish the sand and shale, and crossplot the Vp/Vs and Lambda to detect the distribution of oil or gas. The result is well accepted and can be used as reference for reservoir prediction and hydrocarbon detection of turbidite nearby, which suggests a new thread for subtle reservoir exploration in Bohai Bay Basin.