三维倾斜界面PS转换波CMP道集时距及参数估计  

Moveout and parameter estimation of converted waves at CMP gathers from 3D dipping interface

作　　者：蔡明刚[1,2] 姚陈[1] 王海宁[1] 

机构地区：[1]中国地震局地质研究所,北京100029 [2]中国地震局地质研究所活动构造与火山重点实验室,北京100029

出　　处：《地球物理学报》2012年第7期2432-2440,共9页Chinese Journal of Geophysics

基　　金：中国地震局地质研究所基本科研业务专项(DF-IGCEA-0607-1-1);国家自然科学基金(41104076);国家科技重大专项(2011ZX05008-001-002;2011ZX05035-003-006HZ)资助

摘　　要：在PS转换波资料处理过程中,往往需要联合P波资料提供相应的模型.在实际应用中存在P波和PS转换波层位对比困难.本文仅利用PS转换波数据,通过三维倾斜界面PS转换波CMP道集精确时距关系推导了近似时距解析表达式;分析了PS波的精确与近似时距关系随测线方位、界面倾角与倾向的变化规律及其拟合误差;并讨论了近似时距关系的三个时距参数随方位的变化特征;理论上给出描述时距的三维倾斜界面倾角、倾向、深度、纵波速度和横波速度这5个独立参数的估计方法,并通过理论模拟数据证明了该方法的可行性.In the processing of converted wave data, P-wave data is often needed to be jointed to provide the corresponding model. In the practical application, there is a difficulty in confirming P- wave and PS-wave from the same reflector. In this article PS-wave data is only used and the approximated moveout analytical expressions of PS-waves are derived at the CMP gathers for the three-dimensional dipping interface. The properties and fitness error are discussed about exact and approximate PS moveout which change with survey azimuths, dipping angles and dip orientations. Furthermore, a theoretical parameter estimation method is also given. The five parameters which are dip angle, dip orientation, depth, P-wave velocity and S-wave velocity are used to describe the relation of travel time and distance. An example from a synthetic model is used to show that this parameter estimation method is feasible.

关 键 词：PS波 层位对比 三维倾斜界面 CMP道集 参数估计 

分 类 号：P631[天文地球—地质矿产勘探]