前陆冲断带复杂构造地震成像技术对策

Technical countermeasure of seismic imaging for complex structure in foreland overthrust belt

前陆冲断带复杂构造的地震成像是这一领域油气勘探的关键,地表起伏大、地震资料信噪比低及地下构造复杂是制约该地区地震成像的三大难题,三者相互影响、彼此制约,但核心因素是地表的起伏。对起伏地表作叠前深度偏移是公认的有效方法,但在实际地震资料处理时存在诸多难以逾越的障碍。探索静校正和深度域成像一体化解决方案,重点解决基于起伏地表的剩余静校正和从地表出发的叠前深度偏移处理,是前陆冲断带复杂构造地震成像的技术关键。

Seismic imaging in foreland overthrest belt has become a key to oil ＆ gas exploration. Tough surface relief, low signal to noise ratio, and complex geological structure are three key factors that limit pre-stack depth migration application, of them the tough relief is the core problem. It is recognized that pre-stack depth migration from topography is an effective method to deal with this issue. In practice, there are some difficulties in processing this kind of pre-stack depth migration from topography. The authors are trying to explore an integrated method including static correction and pre-stack depth migration. Topography-oriented residual static correction and pre-stack depth migration are the technical developing trend for complex structure imaging of foreland overthrust.