四川盆地东南缘清虚洞组层序-岩相古地理特征及其油气地质意义  

Characteristics of sequence-based lithofacies and paleogeography of Qingxudong Formation on the southeast margin of Sichuan Basin,China

作　　者：冯伟明[1,2] 谢渊[1,2] 刘建清[1,2] 林家善[1,2] 陈果 

机构地区：[1]中国地质调查局成都地质调查中心,成都610081 [2]国土资源部沉积盆地与油气资源重点实验室,成都610081 [3]中国石油川庆钻探公司勘探开发地质研究院,成都610062

出　　处：《成都理工大学学报（自然科学版）》2016年第1期35-43,共9页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：中国地质调查局项目(12120115004101;1212010782003)

摘　　要：通过对钻井岩屑描述、测井资料解释、野外露头观察、岩石薄片鉴定和样品测试数据的综合分析,将四川盆地东南缘下寒武统清虚洞组划分为1个Ⅲ级层序和3个准层序组,在准层序组内又划分出体系域,在此基础上对清虚洞组层序地层学特征进行了分析,编制了各准层序组沉积体系域的层序-岩相古地理图。sq1-TST期,受持续海侵影响,主要为开阔台地沉积,浅滩规模较小;sq1-HST期局限台地潮坪-潟湖相沉积较发育。sq2-TST期台内滩沉积最为发育,也是清虚洞组颗粒滩相储层最发育的层位;sq2-HST期沉积格局演变为局限台地潮坪环境。sq3准层序组仅残留高位体系域沉积记录,属于频繁暴露的潮坪环境,以膏岩类沉积为主要特征,为灯影组和清虚洞组天然气藏重要的区域性致密盖层发育层位。The Lower Cambrian Qingxudong Formation on the southeast margin of Sichuan Basin can be divided into one Ⅲ-order sequences and 3 parasequence sets. A parasequence set can be divided into some systems tracts. On the basis of the analysis of Qingxudong Formation sequence stratigraphic characteristics, this paper compiles the sequence lithofacies-paleogeographic map of each systems tract. During the development of TST in sql parasequence set, because of the continuous transgression, the open platform facies develop in most regions, and the shoal size is very small. During the development of HST in sql, there better develop the tidal flat and lagoon deposits of the restricted platform. During the development of TST in sq2, the beach facies deposits in the restricted platform most develop, and the grain beach sedimentary body also is the high quality reservoir in Qingxudong Formation. During the development of HST in sq2, the sedimentary pattern is evolved into the tidal flat environment of the restricted platform. In sq3 parasequence set, only HST sedimentary records have remained, belonging to the frequently exposed tidal flat environments. There, the gypsum rocks have most developed, sq3 parasequence set is one of the most important sets of the dense cap rock for the gas reservoirs of Dengying Formation and Qingxudong Formation.

关 键 词：清虚洞组 层序地层 岩相古地理 四川盆地 

分 类 号：TE121.3[石油与天然气工程—油气勘探]