西昌盆地米市凹陷上三叠统白果湾组页岩气地质条件及勘探潜力  

Geological conditions and exploration potential of shale gas of Upper Triassic Baiguowan Formation in Mishi Sag,Xichang Basin

作　　者：何伟[1,2] 陈杨 方坤[3] 刘治成 牟必鑫 魏洪刚 雷玉雪 董雪洁[1,2] He Wei;Chen Yang;Fang Kun;Liu Zhicheng;Mu Bixin;Wei Honggang;Lei Yuxue;Dong Xuejie(Sichuan Institute of Coal Field Geological Engineering Exploration and Designing;Key Laboratory of Shale Gas Evaluation and Exploitation of Sichuan Province;Sichuan Institute of Land Science and Technology)

机构地区：[1]四川省煤田地质工程勘察设计研究院 [2]页岩气评价与开采四川省重点实验室 [3]四川省国土科学技术研究院

出　　处：《中国石油勘探》2021年第5期100-112,共13页China Petroleum Exploration

基　　金：四川省科技基金项目“西昌盆地构造特征及页岩气保存条件研究”(2018JY0625);四川省自然资源厅项目“西昌盆地页岩气资源调查评价和区块优选”(DK-2017-F-008)。

摘　　要：上三叠统白果湾组是西昌盆地米市凹陷重要的页岩层系,为探索其页岩气地质条件及勘探开发潜力,通过地质调查、系统取心、岩心观察、实验分析测试等方法,重点对白果湾组富有机质泥页岩的分布特征、地球化学特征、储层特征、含气特征及保存条件等进行研究,并与国内已获得良好陆相页岩气发现的页岩层系展开对比分析。研究结果表明:(1)米市凹陷白果湾组富有机质泥页岩较发育,厚度较大、有机碳含量适中、热演化程度适中、脆性矿物含量较高、孔隙度较高、含气性较好,具备页岩气形成的有利地质条件;(2)较之于国内其他已获得良好发现的陆相泥页岩,米市凹陷白果湾组泥页岩的孔隙度、有机碳含量、有机质成熟度、含气量等关键参数基本相当;(3)在综合考虑富有机质泥页岩发育程度、埋深、保存和开发等条件下,认为特尔果、七里坝、乐伍、四开、西昌北5个区块是米市凹陷白果湾组页岩气勘探的有利地区,勘探开发潜力较大。The Upper Triassic Baiguowan Formation is a major shale series in Mishi Sag of Xichang Basin.The shale distribution characteristics,geochemical characteristics,reservoir properties,gas bearing properties and preservation conditions are studied by geological survey,systematic coring,core observation,and lab test,so as to investigate its geological conditions and exploration potential of shale gas.Furthermore,these parameters are compared with other domestic continental shale series that have obtained gas discoveries.The results show that:(1)The organic rich shale of Baiguowan Formation is relatively developed in Mishi Sag,with large thickness,moderate organic carbon content,moderate maturity,high content of brittle minerals,high porosity and good gas bearing property,which has favorable geological conditions for shale gas accumulation;(2)The key parameters such as porosity,TOC,R o and gas content of Baiguowan Formation shale in Mishi Sag are basically consistent with those of continental shale that have obtained gas discoveries in China;(3)By comprehensively considering the development degree of organic rich shale,burial depth,preservation and surface engineering conditions,fi ve blocks of Terguo,Qiliba,Lewu,Sikai and Xichang North are selected for favorable areas of shale gas exploration of Baiguowan Formation in Mishi Sag,which have great exploration and development potential.

关 键 词：米市凹陷 白果湾组 页岩气 地质条件 勘探潜力 

分 类 号：TE122.1[石油与天然气工程—油气勘探]