Decoupled elastic Gaussian beam migration for rugged topography
Huang Jianping1, Yuan Maolin1, Duan Xinyi1, Li Zhenchun1, Liu Bin2, Yue Yubo3
1. Geophysics Department, China University of Petroleum (East China), Qingdao, Shandong 266555, China;
2. Shengli Branch, Geophysical Corporation, SINOPEC, Dongying, Shandong 257086, China;
3. Research & Development Center, BGP Inc., CNPC, Zhuozhou, Hebei 072750, China
Abstract：As the development of the seismic exploration, not only acoustic P wave gathers but also elastic wave gathers are inputs for data imaging. Based on surface elevation, surface dip angle, and unseparated multi-component data, we derive decoupled backward-continued vector wavefiled extrapolation formula in terms of elastic-dynamic Gaussian beams by directly decomposing local plane-wave components from complex topography. According to the cross-correlation imaging condition and polarization features of vector wavefield, we obtain PP and polarity-corrected PS migration formulas. We test the proposed method by analyzing elastic wave phenomenon and migrated images, and extracting the ADCIGs from different CDPs for a characteristic rugged topography model data. Numerical results demonstrate the accuracy and flexibility of the method.
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