
Accession Number : ADA327291
Title : Migration Velocity Analysis.
Descriptive Note : Interim rept. JanMar 95,
Corporate Author : COLORADO SCHOOL OF MINES GOLDEN CENTER FOR WAVE PHENOMENA
Personal Author(s) : Liu, Zhenyue
PDF Url : ADA327291
Report Date : MAR 1995
Pagination or Media Count : 97
Abstract : This thesis addresses the development of a general, quantitative representation between the imaged depths and migration velocity. Based on ray theory, I have found that the migration process can be described by using the socalled imaging equations. From this viewpoint, I have studied relationships between the residual moveout and the error of migration velocity in a general context. To handle lateral velocity variations, I used a perturbation method to derive an analytical formula to iteratively update the velocity from residual moveout. My formula estimates the update in velocity by computing a derivative function of imaged depths with respect to velocity in a general background medium context. This formula is more accurate than conventional formulas based on hyperbolic residual moveout when the medium has strongly lateral velocity variations. In addition, I discuss the sensitivity of migrationbased velocity analysis, and show what factors affect the sensitivity. The theory and formulas developed here are available both for the 2D case and for the 3D case. The methodology in this thesis have been tested on synthetic data (including the Marmousi data) and on physicaltank data that are recorded in a scaled earth model.
Descriptors : *MIGRATION, VELOCITY, THESES, IMAGES, DIFFERENTIAL EQUATIONS, PERTURBATIONS, EARTH MODELS, COMPUTERIZED TOMOGRAPHY.
Subject Categories : Numerical Mathematics
Distribution Statement : APPROVED FOR PUBLIC RELEASE