鄂尔多斯盆地南缘宁县—正宁地区延长组地层结构重建及页岩油富集模式探讨  

Re-construction of stratigraphic structure and shale oil enrichment pattern in Yanchang Formation in Ningxian-Zhengning area,southern margin of Ordos Basin

作　　者：胡英杰 李晓光[2] 单俊峰[2] 刘兴周[3] 谷团 鞠俊成[3] 牟春[3] 王宇斯 Hu Yingjie;Li Xiaoguang;Shan Junfeng;Liu Xingzhou;Gu Tuan;Ju Juncheng;Mou Chun;Wang Yusi(CNPC Science and Technology Management Department;PetroChina Liaohe Oilfield Company;Research Institute of Exploration&Development,PetroChina Liaohe Oilfield Company;Qingyang Exploration and Development Branch,PetroChina Liaohe Oilfield Company)

机构地区：[1]中国石油天然气集团有限公司科技管理部,100007 [2]中国石油辽河油田公司 [3]中国石油辽河油田公司勘探开发研究院,124010 [4]中国石油辽河油田公司庆阳勘探开发分公司

出　　处：《中国石油勘探》2024年第5期91-106,共16页China Petroleum Exploration

基　　金：中国石油天然气股份有限公司辽河油田公司重大科技专项“辽河页岩油勘探突破及增储上产关键技术研究”(2024KJZX-03)。

摘　　要：鄂尔多斯盆地延长组页岩油资源丰富,但不同地区勘探研究程度差异大,延长组地层结构及页岩油形成及富集控制因素认识有待深化。利用伊陕斜坡南部宁县—正宁地区新采集的三维地震资料,以及区内的钻井、录井、测井、各类分析测试成果,对延长组地层分布结构和长7段页岩油形成及富集控制因素进行了探讨。综合研究认为,研究区延长组长7—长2段地层具有逐层向湖盆中心进积的楔状地层结构特征;延长组物源主要来自秦岭造山带,各期楔形地层内顺物源方向以河流—三角洲—半深湖—深湖重力流序列充填,具有“同期异相”特征;长7段发育砂质碎屑流及浊流沉积,储层横向变化快,非均质性强,总体属于低孔—特低孔、超低渗致密储层;延长组围绕长7段主力烃源岩,具有上生下储、自生自储、下生上储三种成藏组合类型,长7段主要发育自生自储(夹层)型页岩油,具有优质烃源岩—优势相带—断裂—构造共同控藏特征,其中烃源岩控制页岩油有利发育区,优势相带和断裂控制页岩油富集部位。There are abundant shale oil resources in Yanchang Formation in Ordos Basin,but the levels of exploration and understanding vary greatly in different areas.Therefore,it is necessary to deeply analyze the stratigraphic structure and controlling factors for shale oil accumulation and enrichment in Yanchang Formation.By using the newly acquired 3D seismic data,and combining with well drilling,mud logging,wireline logging and lab test data in Ningxian-Zhengning area in the southern Yishan Slope,the stratigraphic structure of Yanchang Formation is re-constructed,and the controlling factors for shale oil accumulation and enrichment in the seventh member of Yanchang Formation(Chang 7 member)are studied.The comprehensive study results show that the stratigraphic structure of Chang 7 member-Chang 2 member is characterized by wedge-shaped progradation layer by layer towards the center of the lake basin.The sediment source of Yanchang Formation was mainly supplied by Qinling orogenic belt,and the sedimentary sequence of wedge-shaped stratum in each stage was filled with fluvial,delta,semi-deep lake,deep-lake gravity-flow deposits along the direction of sediment supply,which had characteristics of“different sedimentary facies in the same deposition period”.The sandy debris flow and turbidity flow deposits were developed in Chang 7 member,with rapid lateral change and strong reservoir heterogeneity,generally showing a low-porosity to ultra-low porosity and ultra-low permeability tight reservoir.Targeting at the main source rock in Chang 7 member,three types of hydrocarbon accumulation combinations are classified,i.e.,upper source rock and lower reservoir,self-generation and self-storage,and lower source rock and upper reservoir.The self-generation and self-storage(interlayered)type shale oil was mainly developed in Chang 7 member,and shale oil accumulation was jointly controlled by highquality source rock,superior facies zone,faults,and structure,among which the high-quality source rock controlled the favorable zone for s

关 键 词：鄂尔多斯盆地 宁县—正宁地区 延长组 地层结构 长7段 页岩油 控制因素 富集模式 

分 类 号：TE122.1[石油与天然气工程—油气勘探]