Abstract:Based on elastic wave equation,the authors deduced first-order velocity-stress elastic wave-equation with decoupling of compressional wave and shear wave and no converted wave under the condition of two-dimensional inhomogeneous media,which could not only make the implementation of vector migration and ensure the quality of migration,but also avoid the production of other kinds of converted interference wave.Starting from theories of exciting time image condition and reflection coefficient,in combination with first-order velocity-stress elastic wave-equation characterized by decoupling of compressional wave and shear wave and no converted wave,the authors put forward the image condition and migration method suitable for simulated data based on a combined P + S source.This paper has provided the theoretic record migration results of two typical models,and tests show that the method proposed in this paper can make the wavefiled produced by a combined P + S source return to the position accurately,and improve the processing precision of information.
屈念念, 李家斌. 基于P+S波震源的弹性波叠前逆时偏移方法[J]. 物探与化探, 2013, 37(5): 859-865.
QU Nian-nian, LI Jia-bin. THE REVERSE-TIME MIGRATION METHOD FOR PRE-STACK ELASTIC WAVE BASED ON A COMBINED P+S SOURCE. Geophysical and Geochemical Exploration, 2013, 37(5): 859-865.
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