摘要
为了解决三维斜井井间地震数据成像问题,借鉴二维地面地震弯线及宽线处理思路,将三维井间地震成像问题转换成二维成像问题进行研究.利用三维逐段迭代方法对三维斜井井间地质模型进行正演模拟,计算上、下行反射波走时及反射点位置,通过对比正演记录与实际资料的特征,调整地质模型参数获取准确速度场.然后对波场分离后的共炮集数据进行反射波归位,得到共反射点道集数据.最后根据反射点的分布选择一条反射点分布最集中的剖面线,以一定的宽度将剖面线左右的反射点包裹起来;根据叠加宽度划分成大小相等的矩形面元,将面元内的共反射点数据投影到剖面线上进行二维叠加成像.通过模型测试,三维XSP-CDP叠加方法能有效反演地下结构特征,指导三维井间地震采集观测系统的设计并解决不共面斜井叠加成像问题.应用该方法对M地区实际资料进行成像研究,结果表明该方法可有效反演地下三维地质结构特征,为进一步数据处理提供依据.
In order to solve the problem of 3-D deviated well crosswell seismic data imaging,the 3-D cross-well seismic data imaging problems are transformed into the 2-D imaging problems by using the processing method of 2-D ground seismic curved line and wide line. 3-D piecewise iteration method is used in seismic wave field forward of 3-D deviated well cross-well geological model,the travel time of up and down reflection wave and the position of reflection point are calculated. The accurate velocity field is acquired by comparing the characteristics of forward wave field and actual wave field and adjusting the parameters of geological model. Then the common reflection point data is gotten by moving common shot gathers data to real reflection point. Finally the profile line which has the most concentrated reflection point distribution is chosen according to the distribution of reflection points, the reflection points around the profile line are wrapped up in a certain width.The rectangular bins with equal-size are divided into by stacking width,and the 2-D stack imaging is calculated through projecting common reflection data in stack bins on profile line. Model test shows that 3-D XSP-CDP stacking method can effectively inverse the underground structure characteristics,guide the design of 3-D crosswell seismic geometry and solve the stacking problems of deviated well in different planes. The method is used in the imaging study of M area,the results show that this method can effectively inverse the3-D underground structure characteristics,and provides accurate basis for seismic data processing and interpretation.
出处
《地球物理学进展》
CSCD
北大核心
2017年第3期1266-1272,共7页
Progress in Geophysics
