矢量Kirchhoff叠前深度偏移  

Vector prestack depth migration based on Kirchhoff integral equation

作　　者：荣骏召 芦俊[1] 李建峰 王成祥 

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]东方地球物理公司物探技术研究中心,河北涿州072751

出　　处：《石油地球物理勘探》2017年第6期1170-1176,共7页Oil Geophysical Prospecting

基　　金：国家自然科学基金项目(41604119;41425017;41374131;41574126;41504107);中国石油天然气集团公司"弹性波地震成像技术合作研发"项目联合资助

摘　　要：由于传统的Kirchhoff积分法偏移基于标量声学波动方程,没有考虑地震波场的矢量特性,偏移成像的精度较低、保幅性较差。因此,本文从多分量地震波矢量场的特征出发,基于均匀各向同性弹性波波动方程,推导了Kirchhoff积分法矢量偏移公式;利用弹性波波动方程的矢量特性,在偏移过程中将泄漏的地震波信息还原到PP波与PS波分量中,实现了偏移过程中的波场分离。二维理论模型与实际数据的应用结果表明,基于矢量数据的深度偏移方法能够有效消除多分量地震数据的波型泄漏现象,提高偏移成像的精度。Conventional Kirchhoff integral migrations lead inaccurate multi-component seismic imaging and cannot preserve true amplitude due to the scalar acoustic wave equation basis.In this paper,we put forward a vector prestack depth migration based on Kirchhoff integral equation.First we deduce Kirchhoff integral vector migration formula based on multi-component seismic vector field and homogeneous isotropic elastic wave equation.Then we apply it to the prestack depth migration of multi-component seismic data.Using wave equation vector characteristics we recover leaked seismic information PP-and PS-wave components in the migration,and achieve PP-and PS-wave separation.Tests on 2 Dnumerical model and real data prove that the proposed method can eliminate the mode leak and increase the imaging accuracy.

关 键 词：叠前深度偏移 Kirchhoff积分法偏移 矢量 多分量 

分 类 号：P631[天文地球—地质矿产勘探]