鄂尔多斯盆地悦乐地区长6段储层特征及主控因素分析  

Analysis of reservoir characteristics and main controlling factors of Chang 6 member in Yuele area,Ordos Basin

作　　者：张慧芳 魏钦廉 陈曦 毕岭 魏雪珂 ZHANG Huifang;WEI Qinlian;CHEN Xi;BI Ling;WEI Xueke(School of Earth Science and Engineering,Xi’an Shiyou University,Xi’an 710065,China;Key Laboratory of Oil and Gas Accumulation Geology in Shaanxi Province,Xi’an 710065,China;Dingbian Oil Production Plant,Yanchang Oilfield Co.,Ltd.,Dingbian 717111,China)

机构地区：[1]西安石油大学地球科学与工程学院,西安710065 [2]陕西省油气成藏地质学重点实验室,西安710065 [3]延长油田股份有限公司定边采油厂,陕西定边717111

出　　处：《成都理工大学学报（自然科学版）》2024年第4期531-542,560,共13页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家科技重大专项(2016ZX05056);西安石油大学研究生创新与实践能力培养计划(YCS22213069)。

摘　　要：为明确鄂尔多斯盆地悦乐地区三叠系延长组长6段储层发育特征及控制因素,以悦乐地区长6段砂岩储层为研究对象,结合岩心资料、薄片鉴定、扫描电镜、高压压汞与地球物理测井解释等技术方法,从岩石学特征、物性特征及孔隙结构特征多个方面,探讨了沉积作用和成岩作用在储层储集性能方面的重要意义。结果表明:悦乐地区长6段岩性以岩屑长石砂岩和长石岩屑砂岩为主,孔隙类型主要以粒间孔和长石溶孔为主。悦乐地区长6段孔隙度均值为9.27%;渗透率均值为0.142×10^(-3)μm^(2),以特低孔-超低渗储层为主;根据储层分类评价标准,长6段储层由好到差依次分为Ⅰ,Ⅱ,Ⅲ类。沉积环境为研究区长6储层提供物质基础,成岩作用是研究区目的层形成致密储层的关键因素。胶结作用一定程度上充填孔隙、堵塞孔喉,降低储层物性,而溶蚀作用对于改善储层物性具有积极的作用。该研究成果为研究区进一步勘探开发提供借鉴。This study seeks to clarify the characteristics and factors controlling the reservoirs of the Chang 6 member of the Triassic Yanchang Formation in the Yuele area of the Ordos Basin.We combined data on the core,thin-slice identification,scanning electron microscopy,high-pressure mercury injection,and geophysical logging-based explanations to examine the importance of sedimentation and diagenesis for the storage of the reservoir of the Chang 6 member in terms of its petrological and physical characteristics as well as its pore structure.The results showed that the lithology of the Chang 6 member in the Yuele area was dominated by lithic feldspar sandstone,and mainly contained intergranular and feldspathic pores.The average porosity of the Chang 6 member in the Yuele area was 9.27%and its average permeability was 0.142×10^(-3)μm^(2).It thus had ultra-low-porosity and permeability.We used standards of categorization of reservoirs to divide reservoirs of the Chang 6 member into categoriesⅠ,ⅡandⅢin order from best to worst.The depositional environment provided the material basis for the Chang 6 member.Diagenesis was a vital process in the formation of the dense reservoir in the study area.Cementation can be used to fill the pore space and block the throat of the pores to alter the physical properties of the reservoir,while dissolution can enhance its properties.The research here provides guidance for further exploration and development in the area.

关 键 词：鄂尔多斯盆地 悦乐地区 长6段 储层特征 沉积作用 成岩作用 

分 类 号：P618.13[天文地球—矿床学]