HTI介质方位观测PP波反射系数一阶扰动近似  

First-order perturbation approximation of PP wave reflection coefficient for HTI medium based on azimuthal geometry

作　　者：单俊臻 吴国忱[1,2] 龚诚诚 SHAN Junzhen;WU Guochen;GONG Chengcheng(School of Geosciences, China University of Petroleum(East China), Qingdao, Shandong 266580, China;Laboratory for Marine Mineral Resource Evaluation and Detection, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266580,China)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]海洋国家实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266580

出　　处：《石油地球物理勘探》2019年第2期371-379,I0008-I0009,共10页Oil Geophysical Prospecting

基　　金：国家科技重大专项"基于宽方位叠前地震反演的中深层复杂储层表征及油气检测技术"(2016ZX05024-001-008);国家自然科学基金联合基金项目"非常规油气富集机制与地球物理甜点识别"(U1562215)联合资助

摘　　要：五维叠前地震数据具有丰富的炮检距与方位信息,基于五维地震数据所发展的OVT域叠前地震属性分析可以对地下储层进行有效预测。本文在方位观测系统下,基于扰动思想与介质分解理论,推导出一种新的PP波HTI介质反射系数一阶扰动近似公式,突破了传统反射系数近似公式仅适用于小炮检距的局限,进一步提高了五维地震数据中炮检距信息的利用率。计算结果表明,本文所构建的一阶扰动近似公式与传统线性近似公式相比,具有更高的精度,与精确公式的AVO特征具有更高的相似性,为利用中远炮检距信息进行五维地震反演奠定了理论基础。Five-dimensional prestack seismic data contains abundant offset and azimuth information.Newly developed prestack seismic attribute analysis in the offset vector tile(OVT)domain based on five-dimensional seismic data is an effective way to predict reservoirs.In this paper,with the combination of perturbation theory and media decomposition theory,a new first-order perturbation approximation equation of PP wave reflection coefficient for HTI medium based on azimuthal geometry is deduced.The conventional HTI medium reflection coefficient approximation equation is only effective in near offsets,but this newly-deduced equation can better use offset information in five-dimensional seismic data.Calculation results show that the first-order perturbation approximation equation has better accuracy than the conventional linear approximation equation,and AVO characteristics obtained with this approximation are similar with that obtained with the accurate equation,which provides a theoretical basis for five-dimensional seismic inversion with middle and far offset information.

关 键 词：五维地震数据 一阶扰动 反射系数 方位观测系统 AVO 

分 类 号：P631[天文地球—地质矿产勘探]