摘要
复杂山前带具有地表起伏大、地下逆掩推覆构造倾角大、断层关系复杂等地质特征,采用传统有偏VSP数据处理方法难以解决复杂山前带构造成像问题。为此,针对波场分离、静校正、成像方法和速度建模等VSP处理的几个关键环节提出了新的思路和方法。波场分离采用了F-K滤波与逐点偏振滤波相结合的方法,实现了复杂波场的有效分离。为解决静校正问题,改变了VSP成像策略,由传统的时间域成像改为深度域成像,成像后再进行统一基准面校正,从而消除了多方位有偏VSP传统成像剖面间的闭合差。在成像方法上,采用克希霍夫深度域积分成像方法,并根据VSP观测的特点,采用零偏VSP与有偏VSP初至时间计算积分成像中的关键参数———观测时间。将该方法应用于库车复杂山前带相邻两口井的VSP资料处理中,处理结果与钻井结果吻合良好。
Complex piedmont is characterized by rugged surface,large-dip overthrust nappe structure,complex fault relations,etc.Traditional offset VSP data processing method cannot solve the imaging problem for the structures in complex piedmont.Therefore,some new ideas and method were proposed aiming at several key steps for VSP data processing,such as wavefield separation,imaging method and velocity modeling.For wavefield separation,we combined F-K filtering and point-by-point polarization filtering to realize complex wavefield separation.In order to solve the static correction problem,the VSP imaging strategy was changed from traditional time-domain imaging into depth-domain imaging,then datum correction was carried out uniformly after imaging,which can remove the closure difference among the imaging sections obtained from tranditional multi-azimuth offset VSP processing.Meanwhile,Kirchhoff depth-domain integral imaging method was utilized.In terms of the characteristics of VSP observation,zero-offset VSP and offset VSP fist arrival were adopted to calculate the observation time,which is the key parameter in integral imaging.The method was applied to the VSP data processing in two adjacent wells at the complex piedmont in Kuche area,and the result is well coinciding with the drilling data.
出处
《石油物探》
EI
CSCD
北大核心
2012年第2期164-171,105,共8页
Geophysical Prospecting For Petroleum
关键词
山前带
VSP
波场分离
静校正
VSP成像
piedmont
VSP
wave field separation
static correction
VSP imaging
