鄂尔多斯盆地下古生界碳酸盐岩构造-沉积分异及成藏效应  

Tectono-sedimentary differentiation of lower Palaeozoic carbonate rock in Ordos basin,NW China and its implications for hydrocarbon-play generation

作　　者：张晓星 陈安清[1,2] 党牛 张成弓[1,2] 赵俊兴[1,2] 高星 兰叶芳 陈洪德[1,2] ZHANG Xiaoxing;CHEN Anqing;DANG Niu;ZHANG Chengong;ZHAO Junxing;GAO Xing;LAN Yefang;CHEN Hongde(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil&Gas Fields,Changqing Oil Field,Xi’an,Shaanxi 710018,China;School of Mining Engineering,Guizhou University of Engineering Science,Bijie,Guizhou 551700,China)

机构地区：[1]油气藏地质及开发工程国家重点实验室(成都理工大学),成都610059 [2]成都理工大学沉积地质研究院,成都610059 [3]低渗透油气田勘探开发国家工程实验室,中国石油长庆油田分公司,西安710018 [4]贵州工程应用技术学院(矿业工程学院),贵州毕节551700

出　　处：《中国岩溶》2020年第2期215-224,共10页Carsologica Sinica

基　　金：国家自然科学基金项目(41872109);中国石油科技重大专项“长庆油田5000万吨持续高效稳产关键技术研究与应用”(2016E-0514);贵州省科技合作计划项目(黔科合LH字[2016]7050号);内蒙古自然科学基金项目(2018LH04006)。

摘　　要：鄂尔多斯盆地碳酸盐岩是当前的油气勘探热点。当前对鄂尔多斯盆地不同构造区的潜在碳酸盐岩储层及圈闭仍认识不清,阻碍了勘探目标优选。本文通过构造-沉积分异特征分析,揭示了鄂尔多斯盆地早古生代碳酸盐岩台地的构造-沉积分异演化过程及其后期构造改造分异特征。结果表明,受中央古隆起和陆表海环境的控制,盆地南缘以发育镶边礁滩相储层为特征,西缘以发育层状弱镶边礁滩储层为特征,内克拉通则以局限的台地潮坪白云岩储层为特征;三个不同构造-沉积分异区的碳酸盐岩建造都具备成藏条件,但遭受的构造形变具有显著差异,可分为西缘压性构造区、南缘张性构造区和内克拉通稳定构造区;西缘陆内前陆盆地的破碎褶皱带的有利圈闭包括逆掩断层遮挡圈闭和向斜中的次级背斜圈闭;南缘受渭北地堑影响形成的张性构造带发育基底潜山相关圈闭;内克拉通的伊陕斜坡带为一长期保持构造稳定的弱改造的大型单斜构造,以发育岩性圈闭型为特征,岩性圈闭的沉积相分布主要受陆表海旋转潮汐流的约束。The Lower Paleozoic carbonate rock in Ordos Basin is a major target of oil and gas exploration. At present,the potential reservoirs and traps of this rock in different tectonic units of Ordos Basin remain not well understood,which hinders prediction of preferable exploration targets. To solve this problem,based on the analysis of sedimentary and tectonic features,this paper reveals the sedimentary evolution and structural transformation of early Paleozoic carbonate rocks in the Ordos Basin. The results show that controlled by the Central ancient uplift and the epeiric sea environment,the southern margin of the basin is characterized by the development of rimmed reef-shoal facies association,the western margin is characterized by the development of bedded reef-shoal facies association,and the intracratonic basin is characterized by tidal flat of limited platform.The carbonate formations in the three different facies belts have favorable conditions for hydrocarbon-play generation,but their tectonic transformations are significantly different,which can be divided into a compressive tectonic unit in the west margin,extensional tectonic unit in the south margin and stable tectonic unit in the inner craton. Favorable traps in the broken fold belt of the western intracontinental foreland basin include overthrust faulting traps and secondary anticlinal traps in syncline. Traps related to buried hills developed in the south extensional tectonic unit affected by the Weibei graben. The Yishan slope of inner craton is a large monoclinal structure with weak reformation and lots of lithologic traps,and the macroscopic distribution of those lithologic traps are mainly controlled by rotary tidal current of the epeiric sea.

关 键 词：碳酸盐岩 陆表海台地 前陆盆地 潜山构造 岩性圈闭 

分 类 号：P618.13[天文地球—矿床学]