基于块状模型的井间地震运动学正演方法  

Kinematic forward modeling based on block-model for crosswell seismic

作　　者：李辉峰[1] 王彦军[1] 范廷恩[2] 

机构地区：[1]西安石油大学油气资源学院,陕西西安710065 [2]中海石油(中国)有限公司北京研究中心,北京100027

出　　处：《石油地球物理勘探》2011年第2期196-201,156-157,共6页Oil Geophysical Prospecting

基　　金：国家科技重大专项课题(2008ZX05024-01)资助

摘　　要：传统的地面地震正演只考虑了上行反射波信息,没有兼顾透射波、层间直达波以及下行反射波信息,且只适用于简单层状模型,不能适用于井间地震正演。本文根据井间地震自身的特点,运用基于块状单元的建模方法建立了井间地震地质模型,并用块状模型试射法对建立的模型进行了射线追踪,再根据射线追踪结果合成井间地震记录,可以获得较好的应用效果。本文研究表明:基于块状单元的井间地震建模方法能较好地模拟断层、尖灭等复杂地质构造模型;应用基于块状单元的井间地震试射法能够精确地对复杂地质构造模型进行射线追踪,在结构相对简单的模型中迭代收敛较快,但在结构复杂的模型中收敛较慢;根据井间地震射线追踪结果结合正演地震记录可用于识别井间地震波场和叠加成像。In forward modeling methods of surface seismic,only upgoing reflection waves were considered,and the information such as transmission wave,interlayer direct wave and downgoing wave were not involved.Furthermore,these methods are only suitable for simple layered model while it cannot be applied to crosswell seismic.In this paper,a kinematic forward modeling method for crosswell seismic is introduced.First,a model building method based on block units is used to build a crosswell seismic geological model.Then,the trial-ray method is used for ray tracing of the geological model.Finally,crosswell synthetic data are obtained.The results show that this forward modeling method based on block units can simulate complex geological structures with faults,pinchouts and so on.The iterate rays converge more quickly in simple models than in complex models.Crosswell seismic wave fields can be identified by crosswell seismic ray-tracing and croswell synthetic data.

关 键 词：井间地震 射线追踪 块状单元 建模 试射法 正演 

分 类 号：P631[天文地球—地质矿产勘探]