基于重电资料的敦煌盆地地质结构特征研究  

Study on geological structure of the Dunhuang Basin based on gravity and electric data

作　　者：郭涛[1] 李竹强[1] 胡加山[1] 林治模 尹克敏[1] 冯国志 魏敏[1] Guo Tao;Li Zhuqiang;Hu Jiashan;Lin Zhimo;Yin Kemin;Feng Guozhi;Wei Min(Exploration and Development Research Institute,Sinopec Shengli Oilfield Company)

机构地区：[1]中国石化胜利油田分公司勘探开发研究院

出　　处：《中国石油勘探》2019年第3期369-376,共8页China Petroleum Exploration

摘　　要：敦煌盆地整体叠置于塔里木板块东部的敦煌地块上,其油气勘探与研究程度很低,研究敦煌盆地的盆地结构,包括断裂展布、构造格局及基底埋深等,可为进一步勘探综合研究提供地质依据。在对研究区野外露头岩石物性资料、钻测井测试结果统计分析的基础上,结合其他地质资料,总结了岩石、地层密度与电性变化规律。采用层状模型延拓技术消除地形引起的电性畸变效应,使大地电磁反演结果更为精确。采用水平总梯度技术对敦煌盆地的重力资料提取了重力线性梯级带,以此强化盆内断层的线性特征。采用Parker反演法对基底深度进行反演分析。研究结果表明,敦煌盆地发育3套密度层和电性层,盆内区域断裂控制了凹凸相间的构造格局,五墩凹陷基底埋深最大,为最有利的沉积中心。The Dunhuang Basin is generally superimposed on Dunhuang block in the eastern part of Tarim plate. So far, it has been less explored and investigated. Understanding the basin structure, including fault distribution, structural pattern and basement depth, can provide a geological basis for further comprehensive study on exploration. Based on the physical properties of outcrops, drilling/logging results and other geological data, the variations of rock, formation density and electrical properties were identified. The layered model was combined with the continuation technique to eliminate electric distortion caused by terrains, thus deriving more accurate electromagetic inversion results. The gravity linear-gradient zones were extracted from gravity data using the total horizontal gradient technique to enhance the linear characteristics of faults within the basin. The basement depth was analyzed with the Parker inversion method. The results show that: in the Dunhuang Basin, there are three sets of density and electrical layers. The regional faults control the structural pattern of alternate uplifts and sags. And Wudun sag has the deepest basement, which is the most favorable depocenter.

关 键 词：敦煌盆地 重力异常 电性结构 断裂展布 基底结构 

分 类 号：P631[天文地球—地质矿产勘探]