济阳坳陷桩海地区古生界潜山构造特征及形成机制  

Structural characteristics and formation mechanism of the Palaeozoic buried hills of the Zhuanghai area in the Jiyang Depression

作　　者：罗霞[1] 方旭庆[2] 张云银[1] 张云涛 LUO Xia;FANG Xuqing;ZHANG Yunyin;ZHANG Yuntao(Geophysical Exploration Research Institute,SINOPEC Shengli Oilfield Company,Dongying 257015,China;Petroleum Exploration Management Center,SINOPEC Shengli Oilfield Company,Dongying 257015,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257015 [2]中国石化胜利油田分公司油气勘探管理中心,山东东营257015

出　　处：《地学前缘》2021年第1期33-42,共10页Earth Science Frontiers

基　　金：国家油气重大专项(2016ZX05006)课题“渤海湾盆地精细勘探关键技术”;中石化科技攻关项目“济阳坳陷中—古生界构造演化与潜山形成分布(P19015-1)”。

摘　　要：济阳坳陷古生界潜山在经历了残丘山勘探阶段、多样性潜山勘探阶段之后,位于正向构造单元之间的中低位序复杂隐蔽潜山成为勘探主要方向。桩海地区东部紧邻郯庐断裂带,郯庐断裂带的多期构造运动对其产生深刻影响,古生界潜山构造样式非常复杂,并且由于埋藏深,前期地震资料精度低,构造特征认识不清,制约了勘探进展。该研究针对济阳坳陷桩海地区古生界复杂构造特征,运用高精度三维地震、钻井资料和区域应力场研究结果,探讨桩海地区古生界复杂构造特征及其形成机制。桩海地区古生界发育一套稳定的海相海陆过渡相沉积岩系,自下而上依次发育寒武系、奥陶系、石炭系和二叠系。桩海地区古生界发育北西、南北、北东和东西4组走向的断裂,断层类型有正断层、逆断层和走滑断层。北西走向断裂5条,倾角较陡,平面上呈现正、逆相间分布的特点。南北走向断裂3条,剖面呈“花状”特征,为走滑断层。北东走向断裂为正断层,该组断层切割北西向断裂组。东西走向断裂主要是桩海地区潜山的南、北边界断层,该组断层切割北西走向断裂组。断层活动时期可划分为4期。第一期为印支期挤压形成的逆断层,断层贯穿古生界;第二期为晚侏罗至早白垩世构造反转形成的正断层,贯穿中生界和古生界;第三期为晚白垩世挤压形成的逆冲断层,贯穿中生界和古生界;第四期为始新世以来走滑和伸展形成的正断层,断层贯穿古生界、中生界、古近系和部分新近系。不同走向断层交汇切割,形成“棋盘格”式复杂构造。古生界顶面整体呈中部高、东西两侧低的背斜形态。自西向东可划分4排山。复杂的演化过程决定了不同潜山带保留层系和结构类型的差异性。对形成机制的研究结果表明:三叠纪末期—始新世,在郯庐断裂左旋→右旋“往返式”走滑变应力场控制In the Paleozoic buried hills of the Jiyang Depression,the complex middle-lower section between the positive structural units has become the main exploration focus after the initial prospecting of the residual hill and peripheral buried hills.The eastern part of the Zhuanghai region is close to the Tanlu fault zone and has been profoundly impacted by its multistage tectonic movements.The structural style of the Zhuanghai Paleozoic buried hill is very complex,and deep burial can result in low accuracy in the early seismic data,causing ambiguous structural characterization of the zhuanghai area thus greatly hindering the exploration progress.In this paper,we discussed the complex structural characteristics and formation mechanism of the Paleozoic buried hills of the Zhuanghai area,using high precision 3D seismic and drilling data and regional stress field test results.Our results showed that a set of paleozoic stable marine and transitional sedimentary rock series developed in the Zhuanghai area,where Cambrian,Ordovician,Carboniferous and Permian series developed successively from bottom to top.There are four groups of different types of Paleozoic faults in the Zhuanghai area,grouped as the NW,SN,NE and EW-trending faults.The five NW-trending faults are high angle normal and reverse faults;the three NS-trending faults are strike-slip faults;the NE-trending faults,which cut through the NW-trending fault group,are normal faults;and the EW faults,crossing the NW fault group,are mainly the southern and northern boundary faults of the Zhuanghai buried hills.The fault development can be divided into four periods:the first period in the Indosinian when reverse faults formed by Paleozoic compression;the second period from the Late Jurassic to Early Cretaceous when normal faults formed by structural reversions through the Mesozoic-Paleozoic era;the third period in the Late Cretaceous when thrust faults formed by Mesozoic-Paleozoic compression;and the fourth period in the Eocene when normal faults formed by strike slip and e

关 键 词：构造特征 应力场 翘倾运动 郯庐断裂 桩海地区 济阳坳陷 

分 类 号：P542[天文地球—构造地质学]