基于高斯束的对角Hessian在保幅成像中的应用  

Gaussian-beam based diagonal Hessian for amplitude-preserved imaging

作　　者：袁茂林[1,2] 黄建平[2] 邓聪 李振春[2] 

机构地区：[1]中国石油化工股份有限公司勘探分公司,成都610041 [2]中国石油大学(华东)地球物理系,青岛266580 [3]中海石油(中国)有限公司湛江分公司,湛江524057

出　　处：《地球物理学进展》2016年第3期1268-1273,共6页Progress in Geophysics

基　　金：国家重点基础研究发展计划(973)课题(2014CB239006;2011CB202402);国家自然科学基金(41104069;41274124);山东省自然科学基金(ZR2011DQ016);中央高校基本科研业务费专项基金(R1401005A);骨干教师人才支持计划联合资助

摘　　要：稀疏的接收点采样、较窄的采集孔径以及有限的波场带宽等因素导致偏移成像的振幅往往是欠估计的.基于高斯束叠加积分表征的格林函数,可以显示地计算对角Hessian,并将其逆直接应用于高斯束偏移成像,从而实现模型空间的最小二乘偏移.通过常速度模型的数值试验验证了基于高斯束的对角Hessian显示算法的正确性和有效性,将此算法运用到EAGESEG盐丘模型数据和实际资料的最小二乘偏移可以产生振幅均衡的成像结果,尤其在弱照明和阴影区的振幅补偿效果明显.Gaussian beam prestack depth migration only produces blurred images with underestimated amplitude caused by sparse receiver sampling, narrow acquisition apertures, and limited wavefields bandwidth. This distortion can be partially corrected by using the model-space least-squares migration approach,where the diagonal Hessian operator is computed explicitly by using Green＇s function as a Gaussian-beam summation and then its inverse is applied to migrated images. The proposed algorithm for computing the diagonal Hessian is verified by using a constant velocity model.When Gaussian beam based diagonal Hessian algorithm is applied to the SEG / EAGE salt synthetic dataset and real data, improved images with more balanced amplitude especially in areas with low illumination and shadow zones are obtained.

关 键 词：高斯束 对角Hessian 保幅成像 最小二乘偏移 弱照明 

分 类 号：P631[天文地球—地质矿产勘探]