摘要
层速度是一个十分重要而又难以求准的参数。在很多情况下,传统的Dix公式已远远不能满足地质任务的要求。虽然使用在前旅行时反演或叠后地震道波阻抗反演求取层速度的精度较传统方法都有所提高,但两种方法单独使用时都存在较大的局限性。叠前旅行时反演对薄层的反演精度很低,即对薄层的层速度难以求准,而叠后波阻抗反演又易出现整体的漂移,即对厚层层速度的变化控制不好。因此,本文对叠前、叠后联合反演的方法进行了研究,并采用遗传算法进行叠后波阻抗反演,提高了计算的精度。从试算结果可见,效果是明显的。
Interval velocity is very important parameter, but it's hard to be accurately acquired. In many cases,traditional Dix formula hardly meets the requirement of precision in current exploration. Although the precision of interval velocity computed by currently developed prestack travel-time inversion and wave impedance inversion of poststack seismic traces has be greatly improved,but it has larger limitation when each method is used alone. The former has lower precision when it is used for thin-layer, that means, it is difficult to accurately compute the frequently variated interval velocity; on the other hand,the later easily causes the entirety excursion, i. e. the slowly variated interval velocity is not under control. Therefore, the paper studied on prestack and poststack joint inversion and used genetic algorithm to improve the precision in poststack wave impedance inversion. It is showed from test results of both theoretic data and real field data that the method has good effects.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2003年第4期396-399,462-8,共4页
Oil Geophysical Prospecting
