摘要
本文从逆时偏移成像原理出发,利用高阶交错网格有限差分法求解波动方程实现正、反向波场外推。对不同接收方向、不同排列长度及不同道间距所接收的地震数据做反向外推后与正向波场进行对比,分析正、反向波场存在差异的原因,进一步分析不同方向接收的地震数据逆时偏移假象的成因。通过对模型数据结果的分析认为:在逆时偏移过程中由于接收数据的不完整使得反向外推过程中产生新的波场,从而在偏移剖面中形成假象,这类假象可通过多炮叠加来消除;排列长度对逆时偏移成像的影响远大于道间距。
According to the reverse-time migration imaging principle,we use forward and reverse wave field extrapolations with high order staggered-grid finite difference method to solve wave equations.Forward and reverse wave field extrapolations are carries out on seismic data recorded with different receiving directions,different spread lengths,and different receiver intervals.Then the difference between two fields is obtained,and artifacts on seismic data with different receiving directions are analyzed by reverse time migration.We obtain the following observations:A.a new wave field will be generated in backward wave field extrapolation if the seismic data is not complete,and then artifacts will be present on pre-stack reverse time migration,and these artifacts can be suppressed by staking;B.effects of spread length on reverse time migration is larger than receiver interval.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2014年第3期517-522,545,共7页
Oil Geophysical Prospecting
基金
国家自然科学基金项目(41004047和41274123)联合资助
关键词
逆时偏移
接收方向
排列长度
道间距
假象
reverse time migration,receiving direction,spread length,receiver interval,artifacts
