鄂尔多斯盆地马家沟组底部不整合面构造-沉积响应及其成因演化  

Tectonic sedimentary response and genetic evolution of unconformity surface at bottom of Majiagou Formation in Ordos Basin

作　　者：韩骁宇 张成弓[1,2,3,4] 井向辉[5,6] 付斯一 苏中堂[1,2,3,4] 刘子铭 HAN Xiaoyu;ZHANG Chenggong;JING Xianghui;FU Siyi;SU Zhongtang;LIU Ziming(Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;Branch of State Energy Key Laboratory of Carbonate Oil and Gas,Chengdu University of Technology,Chengdu 610059,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an 710018,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,China)

机构地区：[1]自然资源部深时地理环境重建与应用重点实验室(成都理工大学),成都610059 [2]油气藏地质及开发工程全国重点实验室(成都理工大学),成都610059 [3]国家能源碳酸盐岩油气重点实验室成都理工大学分室,成都610059 [4]成都理工大学沉积地质研究院,成都610059 [5]中国石油长庆油田公司勘探开发研究院,西安710018 [6]低渗透油气田勘探开发国家工程实验室,西安710018

出　　处：《成都理工大学学报（自然科学版）》2024年第5期709-726,744,共19页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家自然科学基金项目(42202131);中石油长庆油田科技重大专项(ZDZX2021)。

摘　　要：许多大型油气藏的发现都与不整合面密切相关。在鄂尔多斯盆地马家沟组底部发育有一个不整合面,许多学者称之为“怀远运动”不整合面。该不整合面对于马家沟组底部油气的勘探开发有着重要的理论意义。基于野外剖面、钻井岩心的观察取样,结合显微薄片、测井和地球化学分析,对该不整合面的识别标志、平面分布和成因演化进行讨论。研究表明:该不整合面上下岩性发生了明显突变,不整合面之上为马家沟组含角砾白云岩、白云质石英砂岩或泥质白云岩,不整合面之下为亮甲山组含燧石条、结核的白云岩,或寒武系顶部含溶孔粉-细晶白云岩,多为平行不整合。盆地内地层的缺失程度反映了构造运动的强弱,整体来看怀远运动在盆地呈南强北弱,西强东弱的特征。不整合面的演化可以分为三个阶段,雏形期:张夏组和三山子组沉积期盆地中部隆起,隔绝东西海域,奠定了不整合面的雏形;生长期:冶里—亮甲山组沉积期盆地大部分区域隆起,下伏地层暴露剥蚀,不整合面基本形成;消亡期:马家沟组沉积期海平面上升,海相沉积物覆盖于不整合面之上,形成了不同地层接触的不整合面。不整合面形成的原因主要有两方面,一是早古生代盆地南部受到了秦岭洋板块的俯冲,导致盆地南部抬升遭受剥蚀;二是该时期发生了规模较大的全球海平面下降事件,导致了海水逐渐退出盆地。The discovery of many large oil and gas reservoirs is closely related to unconformity surfaces.An unconformity surface has developed at the bottom of the Majiagou Formation in the Ordos Basin,which many researchers refer to as the“Huaiyuan Movement”induced unconformity surface.This unconformity is theoretically important for the exploration and extraction of oil and gas from the bottom of the Majiagou Formation.In this study,we discuss the criteria of identification,planar distribution,and genetic evolution of this unconformity based on observations,and the sampling of its field profiles and drilling cores in conjunction with analyses of thin microscopic sections,logging,and geochemistry of the area.The results showed that the lithology of the upper and lower parts of the unconformity have significantly changed.Above the unconformity is the Majiagou Formation containing breccia dolomite,dolomite quartz sandstone,and mudstone dolomite,while below it is the Liangjiashan Formation containing flint strips and nodules,and the top of the Cambrian system containing dissolved fine crystal dolomite as pore powder and mostly parallel unconformities.The number of missing layers in the basin reflects the strength of tectonic movement.Overall,the Huaiyuan Movement in the basin can be characterized as strong in the south and west,and weak in the north and east.The evolution of the unconformity can be divided into three stages.The embryonic stage included the Zhangxia and Sanshanzi sedimentary periods as well as the central uplift of the basin that separated the eastern and western sea areas,and provided the foundation for this stage of the unconformity.In the growth period,most areas of the basin were lifted up during the sedimentary period of the Yeli Liangjiashan Formation,while the underlying strata were exposed and eroded to form unconformity surfaces.The extinction period featured a rise in the sea level during the sedimentation of the Majiagou Formation,because of which marine sediments covered the unconformity surfa

关 键 词：鄂尔多斯盆地 怀远运动 不整合面 马家沟组底部 构造-沉积响应 

分 类 号：P618.13[天文地球—矿床学]