Parameters Analysis and Correction Method for Seismic Converted Shear-Wave Splitting Based on Orthogonal Four Components
Liu Lan-feng,*, Liu Shuo, Chen Tian-sheng, Liu Tao, and Jiang Da-jian
1. SINOPEC key laboratory of oil & gas reservoir geophysics, Beijing, 102206, China;
2. SINOPEC Petroleum Exploration and Production Research Institute, Beijing 102206, China
3. China national logging corporation, CNPC, Xi’an, Shanxi, 710021, China
Abstract:
Theory and practice have confirmed that the propagation of converted transverse waves in azimuthally anisotropic media results in shear-wave splitting, causing differences in travel time and reflection amplitude between S1/S2 waves, which reduces the imaging quality and vertical resolution of converted transverse wave. Therefore, eliminating shear-wave splitting is one of the important steps in the imaging processing of converted transverse wave. Due to the limitations of actual data acquisition and signal-tonoise ratio, it is difficult to directly determine a set of orthogonal four components for shear-wave splitting analysis, which cannot achieve good correction processing results. To this end, starting from Alford rotation, an orthogonal four component equation system is derived, and the least squares method is used to stably solve the high signal-to-noise ratio orthogonal four components. Based on this, the crack orientation and fast/slow wave delay are estimated through azimuth and time-delay scanning, and the shear-wave splitting correction and fast/slow wave separation are completed by layer striping from shallow to deep. The synthetic data and actual data calculations show that this method can achieve good azimuthal anisotropy correction, separation of S1/S2 waves, and accurate imaging.
作者简介: Liu Lan-feng, Senior Geophysical Engineer,graduated from China University of Petroleum, Beijing with a PhD in geophysics. He is working at SINOPEC Petroleum Exploration and Production Research Institute, His main interests are geophysical software system development and target-oriented seismic processing and interpretation methodologies.
. Parameters Analysis and Correction Method for Seismic Converted Shear-Wave Splitting Based on Orthogonal Four Components[J]. APPLIED GEOPHYSICS, 2025, 22(4): 1032-1041.