沙漠山地地区地震资料成像处理研究

Research of Seismic Data Imaging Processing in Desert Mountains

在我国中西部广大地区,地表多以沙漠覆盖,沙丘与沙山较发育,油气聚集区多分布于山地陡构造部位,这类地区是油气勘探的潜力区。但是,不可否认的是复杂地表与复杂构造导致地震资料精确成像的处理难度非常大,主要表现为:大沙丘静校正问题严重,地震原始资料信噪比低,速度场横向变化剧烈,复杂构造精确成像难度大。基于此类问题的复杂性,采用针对性的处理思路和处理措施,在处理技术关键点上多下功夫,如沙漠静校正处理技术、沙漠区叠前去噪技术、山地复杂构造叠前时间偏移技术等;同时重视基础处理工作,如精细速度分析和精细初至切除等;最后,结合地震解释人员意见,利用地质背景知识开展速度建模工作,经过优化叠前时间偏移处理参数,最终得到一个较好的成像处理结果。

The earth surface is the desert hill or desert mountain （200 m high） in many places of west China. Deep layers in the desert mountain have a good potential for petroleum accumulation or petroleum exploration. Because the structure and earth surface are complex, the imaging is difficult in seismic data processing： the static processing is difficult in desert hills, the seismic data have lower S/N ratio and the velocity changing is acute in the lateral direction. We resolve key problems using special ways especially in desert static, pre-staek removing noise and the PSTM （pre-stack time migration） of complex structures in the mountain. And we attach great attention to the basic processing, for example, fine velocity analysis and better mute. Finally, we get good imaging data by PSTM optimization and velocity modeling.