摘要
探讨川南-黔北地区下寒武统筇竹寺组(牛蹄塘组)海相泥质烃源岩发育特征及控制因素。在钻井资料及野外剖面调查、对筇竹寺组(牛蹄塘组)沉积相特征分析的基础上,利用烃源岩地球化学分析资料对有机质丰度、类型和成熟度等参数进行评价。结果表明,川南-黔北地区筇竹寺组(牛蹄塘组)发育了一套黑色碳质页岩、黑色-深灰色泥页岩、灰色砂质泥岩与灰质泥岩;沉积相类型为陆棚相,有深水泥质陆棚、深水含磷硅质陆棚及浅水砂质或灰质陆棚3种亚相,其中深水陆棚相发育的碳质页岩、黑色-深灰色泥页岩与深水含磷硅质陆棚相发育的磷块岩、黑色-深灰色碳质含磷页岩及黑色硅质页岩为富烃源岩,浅水陆棚相发育的灰色泥页岩或砂质泥岩、灰质泥岩为一般烃源岩。烃源岩地球化学特征显示,绵阳-长宁拉张槽内及黔北地区一般为好-极好烃源岩,槽外浅水陆棚区为中等-差的烃源岩;以腐泥型(Ⅰ型)为主,生烃能力强,为油型有机质;烃源岩成熟度高,整体达到过成熟阶段(Ro>2.0%)。川南-黔北地区下寒武统烃源岩分布明显受绵阳-长宁拉张槽控制,拉张槽内与黔北地区为烃源岩发育的中心,富烃源岩厚度大;拉张槽外富烃的烃源岩厚度小或没有富烃的烃源岩分布;拉张槽内发育的强生烃区控制了川中—川南海相“下组合”天然气藏的分布,预测宜宾—长宁—筠连—威信一带和内江—资中一带有较好的勘探潜力。
In order to explore the development characteristics and control factors of Lower Cambrian Qiongzhusi(Niutitang)Formation marine argillaceous source rocks in southern Sichuan-northern Guizhou area,the abundance,type and maturity of organic matter were evaluated through the drilling data,field profile investigation,sedimentary facies and geochemical analysis data of source rocks.It shows that the Lower Cambrian in southern Sichuan-northern Guizhou consists of a set of black carbon shale,black-dark gray shale,gray sandy mudstone and gray mudstone.The sedimentary facies of Qiongzhusi(Niutitang)Formation is basically continental shelf facies,including three subfacies of deep cement shelf,deep-water phosphorous silicon shelf and shallow water sandy or calcareous shelf.Carbonaceous shale developed in deep-water continental facies;black-dark gray mud shale and phosphate developed in deep-water phosphorus-containing siliceous continental facies.Black-dark gray carbonaceous phosphorus shale,and black siliceous shale and dark gray mud shale are hydrocarbon rich source rocks.Gray shale,sandy mudstone and lime mudstone developed in shallow-water shelf facies are the general source rocks.Geochemical characteristics of the source rocks indicate that the Mianyang-Changning taphrogenic trough and northern Guizhou area have good-excellent hydrocarbon source rocks and the shallow water shelf outside the trough possesses medium hydrocarbon source rock.The organic matter of the source rock is sapropelic(type I),which is an oil-type organic matters with high hydrocarbon capacity,and the maturity of the source rock is as high as Ro>2.0%(over-maturity stage).Mianyang-Changning taphrogenic trough is the development center of source rocks and obviously controlled the distribution of Lower Cambrian source rocks in southern Sichuan-northern Guizhou.Outside the taphrogenic troughs,the hydrocarbon-rich source rocks have little or no thickness.The high-hydrocarbon area developed in the taphrogenic trough controls the distribution of the lower
作者
罗健
罗小平
陈安清
徐云龙
徐国盛
孙腾蛟
张志鹏
孙延旭
李俊鹏
LUO Jian;LUO Xiaoping;CHEN Anqing;XU Yunlong;XU Guosheng;SUN Tengjiao;ZHANG Zhipeng;SUN Yanxu;LI Junpeng(State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, China;Exploration and Development Research Institute, Post-Doctoral Scientific Research Station of Zhongyuan Oilfield Company, SINOPEC, Puyang 457001, China)
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第5期590-603,共14页
Journal of Chengdu University of Technology: Science & Technology Edition
基金
国家自然科学基金项目(41572133,41872130)。
关键词
下寒武统
拉张槽
沉积相
烃源岩
地球化学特征
川南—黔北
Lower Cambrian
taphrogenic trough
sedimentary facies
source rock
geochemical characteristics
southern Sichuan-northern Guizhou
