VTI 介质各向异性叠前时间偏移技术及应用

摘要

目前地震成像处理中，以各向同性叠前时间偏移为主，其假设地下构造为层状各向同性介质，以直射线或者弯曲射线为主要的走时计算方法。但是在各向异性变化大的地区，该方法导致走时计算不准确，从而造成动校正或者偏移成像存在误差。为此，对 VTI 各向异性介质中走时的计算方法进行讨论，然后结合实际三维地震资料及构造特点，利用 VTI 叠前时间偏移成像技术，探索出一种适合于塔里木地区碳酸盐岩缝洞型储层地震资料叠前各向异性成像技术，处理效率和处理效果均得到提高和改善。%Currently,the conventional pre -stack time migration often assums the underground structures are isotropic medium,and the direct line or curved rays are the main method of travel -time calculation.but in areas with big change in anisotropy,this assumption will cause inaccurate travel -time calculation,resulting in errors of NMO or migration ima-ging.This article first discusses the calculation method of travel time in VTI anisotropic medium,and then combined with three -dimensional seismic data and structure features,with the use of VTI pre -stack time migration imaging techniques, explores a seismic data pre -stack anisotropy imaging technique suitable for carbonate rock cave reservoir of Tarim area. As a result,the processing efficiency and result has been improved.