速度扫描法共聚焦点道集偏移速度分析

英文篇名：Migration Velocity Analysis of Common Focus Point Gathers Based on Velocity Scanning
中文刊名：同济大学学报(自然科学版)
英文刊名：Journal of Tongji University
作者：张凯 ; 李振春 ; 曹景忠 ; 马在田
英文作者：ZHANG Kai 1 ; LI Zhen-chun 2 ; CAO Jing-zhong 1 ; MA Zai-tian 1(1.State Key Laboratory of Marine Geology ; Tongji University ; Shanghai 200092 ; China ; 2.Department of Earth Information and Science ; University of Petroleum ; Dongying 257061 ; China)
中文关键词：共聚焦点偏移 ; 共聚焦点道集 ; 等时原理 ; 差异时差分析 ; 速度扫描 ; 速度分析
英文关键词：common focus point migration ; common focus point gathers ; equal travel-time principle ; differential time shift panel ; velocity scanning ; velocity modeling
出版日期：2005-09-30
机构：同济大学海洋地质国家重点实验室,中国石油大学地球资源与信息学院,同济大学海洋地质国家重点实验室,同济大学海洋地质国家重点实验室上海200092 ,山东东营257061 ,上海200092 ,上海200092
年：2005
期：09
出版单位：同济大学学报(自然科学版)

摘要

共聚焦点(CFP)偏移是基于等时原理,通过激发聚焦和检波聚焦的双聚焦实现叠前深度偏移的地震成像方法.在速度模型正确的情况下,聚焦点响应和它的逆时聚焦算子的聚焦度差异时差(DTS)等于零.此时,二者的相关能量最大.若速度不正确,则差异时差不为零,相关能量弱,但根据差异时差,可以进行算子的更新.基于差异时差分析、速度扫描和相关能量准则,实现了正确算子的求取和偏移速度的估算.模型试算和实际资料试处理表明了所用方法的正确性和有效性.
Common focus point(CFP) migration based on the equal travel-time principle is a kind of pre-stack depth migration method through focusing in both emission and detection.That is,to correct macro velocity model,differential time shift(DTS)is zero between the focus-point response and its time-inverse focus operator.Correlative energy between the operators and focus point responses is maximal.If the velocity is not correct,DTS is not zero any more and the correlative energy is small.But,according to DTS,we could update the erroneous operators.Through velocity scanning and maximum energy criterion,the optimal velocity corresponding to correct focusing operator could be obtained based on updated operators.In this way,the whole velocity could be modified and updated.Model tests and processing of real seismic data show the correctness and validity of our method.

引文

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