基于波射线路径偏移压制多次波

波射线路径压制多次波的反射波成像是在偏移过程去除多次波同时仅对反射波成像.通过在共炮道集和共检波点道集分别计算炮点射线的入射角和检波点射线的出射角计算射线的路径.从炮点入射的射线与从检波点出射的射线的交点形成的走时，若等于观测走时，可以判断此条射线是反射波；反之，若不相等，则是多次波.数值实验表明此方法可以有效地去掉由于多次波能量产生的假成像点和压制多次波，因此界面可以正确归位，同时去掉由于多次波引起的假成像位置.

Multiple removal by wavepath migration.

Multiple removal by wavepath migration is used for discriminating primary reflections from multiple reflections during the migration process. Both the take-off and incidence angles are computed from the data so that rays can be traced from both the source and the receiver positions. An event is a primary reflection as long as the rays intersect and the intersection point has a reflection traveltime equal to the observed traveltime. In contrast, an event is a multiple reflection if the intersection point of the rays has a reflection traveltime different from the observed traveltime. Numerical results for a three-layer model show that multiple removal by wavepath migration can effectively resolve the true interfaces and remove the false structures generated by multiple energy. And the method can effectively remove the migration artifacts generated by surface-related multiples. When near-offset data are not used, the migrated images are nearly free of multiple-related artifacts. However, the method becomes less effective with decreasing source-receiver offset of the traces.