四川盆地侏罗系湖相页岩油气地质特征及勘探开发新认识  

Geological characteristics and new understandings of exploration and development of Jurassic lacustrine shale oil and gas in the Sichuan Basin

作　　者：杨跃明[1] 黄东[2] Yang Yueming;Huang Dong(PetroChina Southwest Oil & Gasfield Company,Chengdu,Sichuan 610051,China;Exploration and Development Research Institute,PetroChina Southwest Oil & Gasfield Company,Chengdu,Sichuan 610041,China)

机构地区：[1]中国石油西南油气田公司 [2]中国石油西南油气田公司勘探开发研究院

出　　处：《天然气工业》2019年第6期22-33,共12页Natural Gas Industry

基　　金：“十三五”国家油气重大专项“四川盆地致密油资源潜力、甜点区预测与关键技术应用”(编号:2016ZX05046006-008)

摘　　要：近年来,中石油、中石化、壳牌等国内外能源公司相继对四川盆地侏罗系自流井组大安寨段湖相页岩开展了油气勘探工作。为了有效地指导湖相页岩油气的相关勘探开发工作,针对该盆地侏罗系湖相油气资源量与储量不匹配、致密储层物性与油气产量不匹配等矛盾,综合岩心、露头、钻井、测井、试油、分析化验等资料,对侏罗系湖相油气系统开展了页岩油气地质特征、勘探开发对象等方面的研究工作。研究结果表明:①四川盆地侏罗系发育自流井组东岳庙段、大安寨段以及凉高山组上段共计3套优质页岩层系,具有源储一体、源储紧邻的特点,是典型的页岩油气发育层系,其中又以大安寨段为典型代表;②大安寨段页岩层系具有有机质含量高、有机质类型好、热演化程度适中、生烃能力强、页岩物性好、储集性能优、脆性矿物含量高、源储配置关系好、页岩厚度大、含油气性好等特征,是典型的页岩油气藏;③通过对大安寨段万吨井的解剖以及页岩有机质含量、热解参数、储层物性等试验数据揭示,该页岩油气藏存在着页岩与介壳灰岩两类储层的油气补给,并且前者的补给能力可能更强,故而页岩层系是侏罗系湖相页岩油气储量有效动用的主要对象;④基于目前的新认识,以页岩油气为勘探对象,通过非常规油气的技术手段,采用水平井+体积压裂技术,该层系一定会取得新的油气勘探突破。结论认为,该项研究成果可以为四川盆地侏罗系湖相页岩油气的资源发现以及储量有效动用等提供理论和技术支撑。Oil and gas exploration has been successively developed in the lacustrine shale of the Da'anzhai Member of the Jurassic Ziliujin Fm in the Sichuan Basin by many companies at home and abroad such as PetroChina, Sinopec, Shell, etc. However, there are still doubts about why the proved reserves is out of proportion to the rich hydrocarbon resources and the oil and gas yield rates unmatched with the tight petrophysical properties of the reservoirs in this study area. In view of this, in combination with cores, outcrops, drilling, logging, oil test, geochemical analysis data, we made research on geological characteristics and exploration targets of shale oil & gas in this study area. The following findings were obtained.(1) Three sets of quality shale layers including the Dongyuemiao, Da'anzhai members in the Ziliujing Fm, and the upper member of Lianggaoshan Fm, are featured by source–reservoir integration and tight connection, among which the Da'anzhai member is typical of well-developed shale reservoirs.(2) The Da'anzhai shale reservoir has such characteristics as high content of organic matters and brittle minerals, moderate thermal evolution degree, strong hydrocarbon generation capacity, good petrophysical behaviors, favorable storage property, good source–reservoir relationship, great thickness, good hydrocarbon-bearing property, and so on.(3) Many test data in detail from a successful well in the Da'anzhai member such as organic matter content, pyrolytic parameter, petrophysical properties, etc., demonstrated that oil and gas supply is quite enough for both shale and crustal limestone reservoirs there, and the former ones are so much stronger that the Da'anzhai is the main target of effective utilization of lacustrine shale oil and gas reserves in the Jurassic strata.(4) Based upon the current new understandings, technical measures for unconventional hydrocarbon resources like horizontal wells and volumetric fracturing, should be adopted to explore shale oil and gas resources in this study area, which will

关 键 词：四川盆地 侏罗纪 自流井组大安寨段 湖相 页岩油气 地质特征 勘探开发新认识 

分 类 号：P618.13[天文地球—矿床学]