复杂介质中地震多次反射波快速正演模拟

基金项目:

中原石油勘探局项目 99-01-02

FAST SYNTHETIC SEISMOGRAMS FOR MULTIPLES IN ANY COMPLEX STRATIFIED MEDIA

1.
Department of Geophysics, China University of Geosciences, Wuhan 430074, China
2.
Research Institute of Exploration&Development, Zhongyuan Petroleum Exploration Bureau, Puyang 457001, China

摘要: 多次波的压制方法研究及多次波对一次波振幅随炮检距变化(AVO) 影响的分析, 需要实用的多次波正演模拟方法.提出了适用复杂层状介质的多次波射线码的计算方法, 使得多次波的射线追踪易于快速实现.同时, 提出了减少多次波计算量的量板表法及插值法.模型的多次波计算结果表明, 多次波振幅的计算精度高, 计算速度快, 对文中设计的模型, 振幅的最大相对误差为1.8%, 而计算时间减少了0.6倍.
- 多次反射波 /
- AVO /
- 快速正演模拟
Abstract: The research of multiple suppression and analysis of influence of multiple amplitude upon primary amplitude-via-offset (AVO) need an effective multiple-modeling method. Thus, a new method has been developed that can automatically calculate multiple ray codes in any complex stratified media, making multiple ray trace fast. Meanwhile, an approach to the computation of multiple amplitude by methods of seeking table and interpolation are discussed. The modeling result shows that the method is of high precision and fast-speed in multiple amplitude calculation. The maximum relative error of amplitude is 1.8% and the spent time by using the method has decreased by 0.4 times one by using accurate ray tracing in the designed model.
- seismic multiples /
- amplitude-via-offset /
- fast synthetic seismograms

图 1 各类多次波的振幅与一次反射波振幅之比随炮检距变化的曲线

Fig. 1. Curves of ratio AVO of multiples to primary wave

下载: 全尺寸图片幻灯片

图 2 射线路径不同的同一类型多次波振幅与一次反射波振幅之比随炮检距变化的曲线

Fig. 2. Curves of ratio AVO of identical multiples with different ray paths to primary wave

下载: 全尺寸图片幻灯片

表 1 多次波反射次数及射线路径

Table 1. Numbers of multiples reflected and sketches of their ray paths

表 2 模型各层弹性参数

Table 2. Elastic parameters of model

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