母岩性质对砾岩储层中自生绿泥石发育的影响及油气储层意义--以准噶尔盆地玛湖凹陷玛北地区下乌尔禾组为例  

Influence of Source Rock Properties on the Development of Authigenic Chlorite in Conglomerate Reservoirs and Its Significance for Oil and Gas Reservoirs: A case study from the Lower Urhe Formation in the Mahu Depression, Junggar Basin

作　　者：晏奇[1] 雷海艳 鲜本忠[1,3] 王剑 罗正江 杨召 贺静[4] 牛君 蒲强 田荣恒 YAN Qi;LEI HaiYan;XIAN BenZhong;WANG Jian;LUO ZhengJiang;YANG Zhao;HE Jing;NIU Jun;PU Qiang;TIAN RongHeng(College of Geosciences,China University of Petroleum(Beijing),Beijing 102249,China;Research Institute of Experiment and Detection,Xinjiang Oilfeld Company,Karamay,Xinjiang 834000,China;State Key Laboratory of Petroleum Resource and Prospecting,Beijing 102249,China;Exploration and Development Research Institute,Changqing Oilfield Company,Xián 710018,China;Faculty of Petroleum,China University of Petroleum(Beijing),Karamay Campus,Karamay,Xinjiang 834000,China;Chongqing Southeast Sichuan Geological Engineering Survey and Design Institute,Chongqing 400038,China)

机构地区：[1]中国石油大学(北京)地球科学学院,北京102249 [2]新疆油田公司实验检测研究院,新疆克拉玛依834000 [3]油气资源与探测国家重点实验室,北京102249 [4]长庆油田分公司勘探开发研究院,西安710018 [5]中国石油大学(北京)克拉玛依校区石油学院,新疆克拉玛依834000 [6]重庆川东南地质工程勘察设计院,重庆400038

出　　处：《沉积学报》2020年第2期367-378,共12页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目(41872113,41702104);国家科技重大专项(2017ZX05009-002,2016ZX05026-007)。

摘　　要：近期取得重大发现的准噶尔盆地玛湖凹陷砾岩油气藏表现出近源、粗粒、深埋、低渗的特征,其中下乌尔禾组(砂)砾岩储层质量与其中自生绿泥石及其伴生的成岩作用密切相关。基于大量铸体薄片观察和扫描电镜、电子探针、X荧光光谱等测试技术,对玛湖凹陷北部地区二叠系下乌尔禾组四段开展了岩石学、矿物学研究,以明确自生绿泥石含量、分布、成因及其对储层的影响,探索火山岩物源供给条件下储层成岩作用差异和优质储层发育规律。研究表明:1)玛北地区自生绿泥石主要为铁-镁过渡型偏富铁绿泥石,以颗粒薄膜、孔隙衬里和孔隙充填产出,物质主要来源于中基性火山物质;2)研究区发育4个砾岩扇体,物源区母岩性质差异较为明显。玛东斜坡夏盐扇、玛东扇砾岩储层中发育大量的自生绿泥和浊沸石,玛西斜坡夏子街扇和黄阳泉扇砾岩储层自生绿泥石缺乏,以浊沸石胶结为特点。不同母岩性质砾岩体在埋藏成岩演化过程发育不同的成岩序列;3)砾岩储层质量与物源区母岩性质关系密切,玛东斜坡自生绿泥石和浊沸石的析出导致储层胶结程度高、整体致密,储层质量取决于后期裂缝的改造。玛西斜坡缺乏自生绿泥石,浊沸石的析出抵抗了储层压实作用,保存了少量原生孔隙,为后期酸性流体的注入和浊沸石的溶蚀提供了可能。其中构造高部位浊沸石溶蚀程度高,储层质量好。The conglomerate reservoirs discovered recently in the Mahu Depression,Junggar Basin have been characterized as near-source,coarse-grained,deep-buried,and low-permeability. The conglomerate reservoir quality of the Lower Urhe Formation is closely related to the authigenic chlorite and its associated diagenesis. Petrology and mineralogy were studied for the Permian Lower Urhe Formation in the northern Mahu Depression using thin section observation,scanning electron microscopy,electron probe,and X-ray fluorescence(XRF)spectrum to clarify the content,distribution,and genesis of authigenic chlorite and its impact on reservoir quality and to explore the reservoir difference mechanism of diagenesis. The research shows that:1)The authigenic chlorites in the northern Mahu Depression belong to iron-magnesium transitional iron-rich chlorites,produced by grain-coating,pore lining,and pore filling and controlled by iron-magnesium-rich volcanic material;2)Four conglomerate fans were developed in the northern Mahu Depression,and the provenance properties of the source rock are obvious. The Xiayan and Madong fans along the slope of eastern Mahu Depression are characterized by the development of a combination of authigenic chlorites and laumontites,while both the Xiazijie and Huangyangquan fans along the slope of the western Mahu Depression are characterized only by laumontite cementation. Different conglomerate reservoirs from various source rocks are characterized by obvious differences within their diagenetic sequence;3)The conglomerate reservoir quality is closely related to the properties of their source rock. The precipitation of authigenic chlorites and laumontites along the slope of the eastern Mahu Depression leads to high cementation and tightness overall. The good reservoir depends on later fracturing. Due to the lack of authigenic chlorites along the slope of the western Mahu Depression,the development of laumontite resists normal compaction and retains some of the primary pores,providing possible migration channels

关 键 词：砾岩储层 母岩性质 自生绿泥石 储层质量 火山岩 

分 类 号：P618.13[天文地球—矿床学]