摘要
如何在低勘探程度地区提取地层速度一直是地球物理勘探面临的难题,由于低勘探程度地区钻井资料十分稀少,需要借助地震资料才能够实现全区地层速度提取,而地震资料具有一定的频带,直接通过地震资料反演获取的地层速度缺失低频分量,必须进行低频速度补偿.本文提出一种以地震资料为主、测井资料为辅的地层速度提取方法.首先,通过有色反演方法提取地震资料的相对速度分量;然后,利用地震速度谱资料构建低频速度模型,低频速度模型构建受层序地层格架约束;最后,将低频和相对速度分量合成为宽频带的地层速度.应用该方法提取琼东南盆地深水区地层速度,结果表明提取的地震绝对速度精度较高,可作为该地区地层速度提取的一种行之有效的方法.利用该方法获得的高精度地层速度剖面在中央峡谷水道砂体的速度-岩性识别和地层压力预测方面获得良好的应用效果.
How to extract accurate formation velocity in low exploration area is a difficult problem in geophysical prospecting.Because the borehole data is sparse in low exploration areas,extracting formation velocity must be realized through seismic data.However,seismic data has limited band width.Due to the absence of low frequency velocity component,the formation velocity obtained directly from seismic inversion must be compensated with low frequency velocity.Based on seismic and well logging data,author proposes a new method to extract formation velocity.Firstly,relative velocity is obtained from seismic data by colored inversion.Then,low frequency velocity model constrained by sequence stratigraphic framework is built through seismic velocity spectrum.Finally,absolute velocity with broad-band is obtained by integrating low frequency velocity component with relative velocity component.Through application in the deepwater area in Qiongdongnan basin,the result shows better precision and this method is available for extracting formation velocity in low exploration areas such as deep water area.This method has been applied in velocity lithology analysis and predication of formation pressure using seismic data and gotten good effects.
出处
《地球物理学进展》
CSCD
北大核心
2014年第3期1337-1342,共6页
Progress in Geophysics
基金
国家十二五科技重大专项课题2<南海北部深水区潜在富生烃凹陷评价>(2011ZX05025-002)资助
关键词
地层速度
低频模型
相对速度
琼东南盆地深水区
formation velocity
low frequency model
relative velocity
deep water area in Qiongdongnan basin
