川西南部灯影组展布特征新认识及油气地质勘探意义  

New understandings of distribution characteristics of SinianDengying Formation in southwestern Sichuan Basin and its significance of oil and gas geological exploration

作　　者：文龙[1] 王文之[1] 李林娟[2] 洪海涛[1] 罗冰[1] 张玺华[1] 彭瀚霖[1] 李堃宇 贾敏[1] 田兴旺[1] Wen Long;Wang Wenzhi;Li Linjuan;Hong Haitao;Luo Bing;Zhang Xihua;Peng Hanlin;Li Kunyu;Jia Min;Tian Xingwang(Research Institute of Exploration and Development,PetroChina Southwest Oil&Gasfield Company;PetroChina Southwest Oil&Gasfield Company)

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

出　　处：《中国石油勘探》2020年第3期56-65,共10页China Petroleum Exploration

基　　金：国家科技重大专项“四川盆地及邻区下古生界—前寒武系成藏条件研究与区带目标评价”(2016ZX05004-005);中国石油天然气股份有限公司重大科技专项“西南油气田天然气上产300亿立方米关键技术与应用”(2016E-0602)。

摘　　要：四川盆地震旦系灯影组勘探成效显著、潜力巨大。对四川盆地川西南部开展野外露头、岩心岩石学特征和地球化学分析,并结合地震资料综合研究认为:川西南部汉王场构造汉深1井震旦系灯影组具有贫藻富硅、Ca及Mg含量相对低、Si含量高、δ13C及δ18O偏低的特征,与灯四段在岩性特征、常量元素和同位素含量上基本一致,所钻揭的灯影组层位归属为灯四段;井震结合预测,川西南部灯四段主要在成都—犍为以西地区分布,厚200~300m,在盆地内分布面积达1.5×10^4km^2,向南一直延伸到西昌、云南地区。灯四段厚度向德阳—安岳裂陷内逐渐减薄,具有缓坡型台地边缘特征。川西南部地区灯四段储层发育,紧邻裂陷槽内寒武系优质烃源岩,成油期处于古隆起高部位,发育古油藏,后期历经多次构造运动,油裂气重新调整聚集,具备形成构造型、构造—岩性复合型、构造—地层复合型等气藏的地质条件,邛崃—大兴场—眉山地区是勘探的有利区带。The Dengying Formation of the Sinian system in the Sichuan Basin has significant exploration effects and great potential.The petrological characteristics and geochemical analysis of outcrops and cores in southwestern Sichuan Basin were carried out combining with seismic data.The comprehensive study shows that,the Sinian Dengying Formation in Well Hanshen-1,located in the Hanwangchang structure in southwestern Sichuan,is characterized by poor algae content,rich silicon content,relatively low Ca and Mg content,high Si content,lowδ13C andδ18O content.As it is basically consistent with the fourth member of Dengying Formation in lithologic characteristics,major elements and isotopic content,it is considered that the penetrated strata is the fourth member of Dengying Formation.According to the prediction of well-seismic combination,the Deng-4 member in southwestern Sichuan Basin is mainly distributed in the west of Chengdu-Qianwei area,with a thickness of 200-300m and a distribution area of 1.5×10^4km^2 in the basin,which extends southward to Xichang and Yunnan areas.The thickness of the Deng-4 member is gradually thinning towards Deyang-Anyue rift,which has the characteristics of gentle slope platform margin.The reservoirs in the Deng-4 member are well developed in the southwestern Sichuan area,which is near the Cambrian high-quality source rocks in the rift.In the oil generation stage,the reservoirs were located at the high position of the paleo-high,so the paleo oil reservoirs were formed.In the later stage,after several tectonic movements,oil cracking gas was re-adjusted and re-accumulated.It had the geological conditions to form gas reservoirs of structural type,structural-lithologic type and structuralstratigraphic type.The areas of Qionglai-Daxingchang-Meishan are favorable zones for petroleum exploration.

关 键 词：四川盆地 灯影组 地层展布 同位素 成藏条件 缓坡型台缘 

分 类 号：TE112[石油与天然气工程—油气勘探]