约束层析反演在砂砾岩体速度建模中的应用  

Application of constrained tomographic inversion in seismic velocity modeling of glutenite bodies

作　　者：金昌昆 秦宁[1] 关键[1] 宗兆云[2] 李坤 刘群强[1] JIN Changkun;QIN Ning;GUAN Jian;ZONG Zhaoyun;LI Kun;LIU Qunqiang(Geophysical Research Institute,Shengli Oilfield Company,SINOPEC,Dongying,Shandong 257022,China;School of Geoscienes,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]中国石化胜利油田分公司物探研究院,山东东营257022 [2]中国石油大学(华东)地球科学与技术学院,山东青岛266580

出　　处：《石油地球物理勘探》2023年第6期1392-1397,共6页Oil Geophysical Prospecting

基　　金：中石化科技攻关项目“全节点高密度地震技术研究及应用”(PZ1061);胜利油田科技攻关项目“砂砾岩体高精度速度建模及成像技术研究”(YKW2109)、“基于国产超算集群的高效叠前偏移技术研究(一期)”(YKW2302)和“面向海量数据的叠前偏移成像软件”(YKF2309)联合资助

摘　　要：砂砾岩体广泛存在于断陷湖盆陡坡带,可发育多种油气藏类型,勘探潜力较大。但由于其空间展布及叠置关系复杂,与围岩有较大速度差异,常规的成像域网格层析建模方法难以获取精细速度模型。为此,基于成像域网格层析反演方法,借鉴层位约束的思想,结合地震解释得到的岩体空间分布信息划定重点反演区域,并引入对数型障碍函数,通过施加不等式约束条件限制岩体速度变化范围,提出一种成像域约束层析反演方法,以提高砂砾岩体的建模精度。在BS工区的应用结果表明,与原有的网格层析模型相比,该方法建立的速度模型与成像剖面中的岩体分布更吻合;与融合建模结果相比,能更好地反映出砂砾岩体内部的速度变化,相应的成像剖面质量也有一定提高。Glutenite bodies widely exist in steep slope zones of faulting depression basins,and they can develop various hydrocarbon reservoir types with great exploration potential.However,due to their complex spatial distribution and overlap relationship,and large velocity differences with the surrounding rocks,it is difficult to employ the conventional grid tomographic modeling methods in the imaging domain to obtain their refined models.Thus,based on the grid tomographic inversion method in the imaging domain,this paper proposes a constrained tomographic inversion method in the imaging domain to improve the modeling accuracy of glutenite bodies.The thought of layer constraints is adopted,and the spatial distribution information of glutenite bodies obtained from seismic interpretation is combined to delineate key inversion regions.Meanwhile,it introduces the logarithmic barrier function and limits the velocity variation range of the glutenite bodies by applying inequality constraints to improve the modeling accuracy of the bodies.The application results in the BS work area indicate that compared with the original grid tomographic model,the velocity model built by this method is more consistent with the glutenite body distribution in the imaging section.Compared with the results of the fusion model,it can reveal the velocity changes inside the glutenite body,and the quality of its corresponding imaging section is also improved.

关 键 词：砂砾岩体 层析 偏移速度建模 深度域 内罚函数 不等式约束 

分 类 号：P631[天文地球—地质矿产勘探]