起伏地表下P-SV转换波动校正  

NMO of Converted Wave under Irregular Topography

作　　者：孙超 SUN Chao(Shandong Coal Field Geological Planning and Surveying Institute,Ji'nan 250104,China)

机构地区：[1]山东省煤田地质规划勘察研究院,济南250104

出　　处：《华北地震科学》2020年第2期9-12,27,共5页North China Earthquake Sciences

基　　金：山东省地勘基金项目(鲁勘字(2018)23号);山东省地勘基金项目(鲁勘字(2019)13号)。

摘　　要：P-SV转换波勘探是一种行之有效的地震勘探技术。基于地表一致性假设,P-SV转换波动校正过程中将地表假设为平坦地形。而随着地震勘探向复杂地区的深入,地表起伏大、高速老地层出露的问题,使得地震数据难以满足地表一致性假设。因此,现行的基于地表一致性的P-SV转换波动校正处理方法不能很好地对P-SV转换波进行动校正,影响转换波勘探的准确性。为此,本文从转换波的运动学特征出发,建立了起伏地表下P-SV转换波动校正方程,并构建了起伏地表条件下转换波动校正方法。通过理论模型模拟计算了起伏地表下P-SV转换波动校正方法,结果表明采用起伏地表下的转换波动校正方程能够取得较好的动校正效果,为P-SV转换波速度分析提供了一种行之有效的方法技术。P-SV converted wave exploration is an effective seismic exploration technology.Based on the assumption of surface consistency,the surface is assumed to be flat in the process of P-SV Normal Move-Out(NMO).However,with the development of seismic exploration into complex areas,the problem of large surface relief and high-speed exposure of old strata make the seismic data difficult to meet the assumption of surface consistency.Therefore,the current P-SV converted wave NMO method based on surface consistency cannot work on the P-SV converted wave,which affects the accuracy of converted wave exploration.In this paper,based on the kinematic characteristics of converted waves,the P-SV converted wave NMO equation and the converted wave NMO method under the undulating surface are established.The new method is tested by the theoretical model simulation.The results show that the new NMO equation can achieve better NMO effect,which provides an effective method and technology for P-SV converted wave velocity analysis.

关 键 词：地震勘探 P-SV转换波 起伏地表 动校正 

分 类 号：P613.4[天文地球—矿床学]