井间地震弯曲射线层析成像  

Tomographic image of curved rays in borehole to borehole seismic survey.

作　　者：张树林[1] 朱介寿[2] 贺振华[2] 

机构地区：[1]大庆石油管理局物探公司 [2]成都地质学院

出　　处：《石油地球物理勘探》1992年第2期270-278,共9页Oil Geophysical Prospecting

摘　　要：本文利用井间透射波旅行时,并考虑井间地震射线弯曲情况进行了速度层析反演。对于井间断面采用三角形剖分,并给定单元节点的速度和位置参数;单元内的速度梯度为常矢,任一位置处的速度可由二维线性插值求取。采用速度较快的打靶法进行两点射线追踪;用奇异值分解(SVD)法求解大型稀疏病态方程组。另外,文中给出了两个理论模型。试验的结果表明:文中所述方法的成像质量较高,其可行性和实用性较强。Velocity tomographic inversion is performed by using travel times of transmit- ted waves from one borehole to another and considering curvatures of seismic rays. We take a triangular grid,where velocity and position parameters of each grid-point must be given.Velocity gradient in an element is a constant vector,and the velocity at each position may be calculated by making two-dimensional linear interpolation. Fast“hitting target”method achieves ray tracing between two points.Sparse ill-con- ditioned system of equations are solved by doing singular value decomposition (SVD). In addition,two theoretical models are given.Trial results say the method results in good im- age and has good applicability.

关 键 词：井间地震 层析成像 奇异值分解 

分 类 号：P631.4[天文地球—地质矿产勘探]