Abstract:In order to make full use of the diffractions in seismic record to describe small underground structures (faults, fractures, holes, etc.), it is necessary to separate weak diffractions from seismic full-wave field and image diffractions separately. In dip-angle common imaging point gathers (CIGs), a separating and imaging method of diffractions based on high-resolution Radon transform on an iterative model shrinking approach is proposed. This method considers the morphological difference in diffracted and reflected events. It uses an iterative shrinkage threshold algorithm (ISTA) to obtain the sparsity of Radon model through model shrinkage steps in time domain and solve the problem that the separated effect of diffraction wave field caused by poor focusing of reflection and diffraction energy group is not ideal in conventional Radon transform. On the basis of programming algorithm, the method can effectively separate diffracted waves and has strong anti-noise ability on model data. On real data, the computing efficiency of the method is about twice than that of the conventional IRLS at more than 20 iterations, proving it applicable for real seismic data.
罗腾腾, 徐基祥, 孙夕平. 应用迭代收缩高分辨率Radon变换的绕射波分离与成像方法[J]. 石油地球物理勘探, 2021, 56(2): 313-322.
LUO Tengteng, XU Jixiang, SUN Xiping. Diffraction wave separation and imaging based on high-resolution Radon transform on an iterative model shrinking approach. Oil Geophysical Prospecting, 2021, 56(2): 313-322.
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