PS转换波共转换点的几种计算方法及实际应用

Calculation procedures for common conversion points of PS converted waves and their application

1. 中国石油集团地球物理勘探局,河北涿州072751;2. 石油大学,北京102200

1. Petroleum Geophysical Prospecting Bureau of China National Petroleum Company, Zhuozhou 072750,China;2. University of Petroleum, Beijing 102200,China

目前常用的共转换点计算公式是在单层均匀介质模型条件下导出的。Thomsen于 1999年提出多层介质条件下的共转换点计算公式,其假设前提与实际情况更为接近,对纵横波速度比的定义也更为精细。通过采用上述 2种不同计算方法对实际资料进行共转换点分选及叠加处理并对比,基于多层介质模型的算法的叠加效果明显优于单层介质模型的算法.

The commonly used formula so far for common conversion point (CCP) calculation are derived under assumption of homogeneous medium model with single layer. Thomsen proposed in 1999 a new set of formula for CCP estimation under assumption of multilayerd medium. Due to the multilayered medium is more close to the real situation, Thomsen’s definition of velocity ratio between compressional and shear waves is more accurate. We performed CCP sorting and stacking on real data with the above mentioned calculation procedures and compared their results, which reveals that the multilayed calculation procedure is superior to single layered one.