正交各向异性叠前时间偏移技术及应用OA

There is relatively little research on the application of pre-stack migration technology for ORT media,especially for land seismic data.The imaging accuracy by the conventional pre-stack time imaging processing approach is insufficient.The principle of the Kirchhoff orthorhombic pre-stack time migration is introduced,and a five-parameter sensitivity analysis is conducted.The research has been conducted on time-domain orthorhombic anisotropic five-parameter initial modeling,a coherent spectrum-picking method for azimuthal anisotropy correction,an automatic high-density residual curvature-picking technique in the OVT domain,and an orthorhombic anisotropic nonlinear tomography inversion technique in the time domain.A set of orthorhombic anisotropic pre-stack time-migration processing flow has been established,from initial modeling and model updating to migration imaging.The processing flow and key technology have been applied in southern Sichuan.They improve the imaging quality of gypsum salts and underlying structures and enhance the quality of middle-to far-offset traces.