摘要
井间地震正演模拟是在给定地层参数及边界条件的情况下求波动方程数值解的过程.本文详细推导了井间二维声波方程四阶差分方程;根据假设的包含楔形体和丘状体的理论地层模型,对其波场进行了模拟计算分析;据胜利油田垦71区块两口井的实际声波测井资料建立了精细速度模型,对其正演模拟的合成记录波场进行分析,并把合成记录反射波成像与实际的过井三维地震剖面进行了对比,验证了所设计观测系统的合理性.
Forward simulation in crosswell seismic is the process of solving the numerical solution of the wave equation under the defined formation parameters and limited condtions.In this paper,I present a detailed deduction for fourth-order difference equation of crosswell two-dimensional acoustic equation: By using a theoretical model including a wedge and a mound,the corresponding wave field is detailedly analyzed.By a delicate velocity model according to two real wells logging data in the Ken71 block of Shengli oil field,we analyzed the computed synthetic seismogram and gived a comparison between inversion result of reflection wave of model and corresponding 3D seismic profile across the two wells.It verified the rationality of our designed observation system.
引文
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