Tomography Velocity Inversion by Well Constraint Based on the Angle Domain Common Imaging Gathers
详细信息
- 责任者：Qin Ning (School of Geosciences ; China University of Petroleum ; Qingdao 266555 ; China) ; Li Zhenchun
- 刊名：Oil Geophysical Prospecting
- 出版年：2011
- 卷期：46(5)
- 关键词：走时 ; traveltime ; 速度分析 ; velocity analysis ; 层析技术 ; tomography
- 页码：p.725-731
- 图表：4 illus., 22 refs.
- 分类号：1600
- 出版序号：1993
- issnNo：ISSN1000-7210
- isbnNo：CN13-1095/TE
摘要
///A travel-time tomography method proposed in this paper mainly gets travel-time residual on the basis of angle domain common imaging gathers(ADCIGs) and controls the precision of tomography inversion by well constraint.The key implementation steps are as follows: 1.Build the initial tomography velocity model using a layer interface picked from pre-stack depth migration;2.Get ADCIGs according to selected angle range and calculate the travel-time residual of each layer;3.Calculate the sensitivity matrix corresponding to the ADCIGs;4.Establish the inversion equation systems by adding the regularization and well constraint to inverse the slowness update;5.Determine if the velocity precision meets the demand or not through the flatten degree of ADCIGs events.The results of model dataset and filed dataset have proved that this method is easy to carry out,without considering complex reflection problem.And the velocity updates of every iteration are obtained based on pre-stack depth migration of previous step,which can achieve velocity field with high precision.