胜利油田马寨深层复杂构造地震成像的探讨

Approaching of seismic imaging in deep and complicated structure of Mazhai area,Shengli Oilfield.

付金华 ,何端武 .胜利油田马寨深层复杂构造地震成像的探讨 .石油地球物理勘探 ,2 0 0 1,36 (6 ) :76 1～ 772 深层复杂构造地震勘探是当前具有挑战性的一项研究领域 ,胜利油田马寨地区是一个典型的实例。由于马寨地区地震资料差 ,难以得到合理的地质构造解释。根据地质经验 ,本文建立了马寨速度模型。借助有限差分纵波波场模拟方法得到了叠前地震记录 ,并对其进行了偏移成像试验。数值试验结果证明 ,当前广泛使用的叠后时间偏移技术难以使马寨地区的地震资料正确成像 ,并且从理论上讨论了叠加过程对复杂地质构造成像的负面影响。同时 ,利用叠后深度偏移、叠前时间偏移和叠前深度偏移方法分别对马寨速度模型合成地震记录进行了成像试验 ,为进一步寻求更合适的成像技术提供了参考依据。

Seismic exploration of deep and complicated structure is a challenging study field at present.The Mazhai working area,Shengli oilfield is a typical real case.It is impossible to obtain reasonable interpretation of geological structures because of poor seismic data in Mazhai area.In the paper,I made a Mazhai velocity model on the basis of geological acknowledge and obtained prestack seismic data by the aide of finite-difference acoustic wave field modeling method,which was taken for migration tests.Numerical results proved that it is difficult to correctly image the Mazhai seismic data with the presently extensively used poststack time migration technique and theoretically demonstrated the negative effect of stacking process on correct imaging of complicated geological structures.Meanwhile,I made imaging tests for the Mazhai synthetic seismogram by using a poststack depth migration method,a prestack time migration method and a prestack depth migration technique separately and provided more reference basis for selecting reasonable migration techniques.