叠合盆地古老地层热史恢复及应用——以四川盆地川中古隆起震旦系-寒武系为例  

Reconstruction and application of thermal history of old strata in superimposed basin:A case study on the Sinian-Cambrian in the central Sichuan paleo-uplift of the Sichuan Basin

作　　者：施亦做 汪泽成[1] 徐秋晨 胡圣标[3] 黄士鹏[1] 姜华[1] 江青春[1] 付小东 李文正 刘人和[1] 刘静江[1] 翟秀芬[1] SHI Yizuo;WANG Zecheng;XU Qiuchen;HU Shengbiao;HUANG Shipeng;JIANG Hua;JIANG Qingchun;FU Xiaodong;LI Wenzheng;LIU Renhe;LIU Jingjiang;ZHAI Xiufen(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;Oil and Gas Survey,China Geological Survey,Beijing 100037,China;Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;PetroChina Hangzhou Research Institute of Geology,Hangzhou,Zhejiang 310023,China)

机构地区：[1]中国石油勘探开发研究院 [2]中国地质调查局油气资源调查中心 [3]中国科学院地质与地球物理研究所 [4]中国石油杭州地质研究院

出　　处：《天然气工业》2024年第8期29-43,共15页Natural Gas Industry

基　　金：国家自然科学基金青年科学基金项目“古老海相地层热史恢复——以川东地区震旦系—下古生界为例”(编号:42002173);中国石油天然气股份有限公司科技项目“陆相深层超深层油气富集规律与勘探评价技术研究”(编号:2021DJ02)。

摘　　要：由于古温标样品稀缺、热史复杂、方法单一且难以进行有效表征等原因,叠合盆地古老地层热史恢复一直是沉积盆地热史研究的难点问题之一。为此,以四川盆地川中古隆起震旦系灯影组与寒武系沧浪铺组为例,探索了可指示叠合盆地古老地层热史的有效古温标组合与方法体系,将传统古温标与具有不同封闭温度的低温热年代学古温标相结合,恢复了川中古隆起震旦系—寒武系重点层系热史,分析了在不同构造阶段的地层热演化特征、主要构造—热事件的热效应以及古地温对油气成藏关键过程的控制作用,并探讨了不同古温标在叠合盆地古老地层热史恢复中的适用性与应用意义。研究结果表明:①川中古隆起高石梯—磨溪地区灯影组与沧浪铺组主要经历了2期升温和2期冷却过程,在2期升温过程中,川中古隆起高磨地区灯影组达到的最高古地温接近240℃,沧浪铺组约200℃,在该区域峨眉山地幔柱事件未产生决定性影响;②古地温控制下,德阳—安岳裂陷区下寒武统烃源岩的热演化进程、高磨地区灯影组储集层的埋藏溶蚀高峰及油气充注成藏过程三者可相关联,而裂陷东翼下寒武统烃源岩热演化与之相比呈现出“滞后性”;③前陆盆地演化期的深埋藏升温是有机质向高—过成熟转化、原油裂解成气的主要阶段,燕山晚期—喜马拉雅期的构造抬升可能为后2期的天然气充注提供了驱动力。结论认为,不同类型古温标可对叠合盆地古老地层所经历的不同阶段的热演化过程与构造—热事件起到指示作用,对叠合盆地古老地层热史进行恢复,可采用多古温标—多地层联合的方法,并基于古温标数据分析,结合地层埋藏史与盆地古热流数值模拟等结果,可对关键时期的热史路径进行多手段约束。Reconstruction of the thermal histories of old strata in superimposed basins has always been one of the difficulties in studying the thermal history of sedimentary basin,due to scarce sample of palethermometer scale,complex thermal history,and difficult effective characterization of thermal history by a single method.Taking the Sinian Dengying Formation and the Cambrian Canglangpu Formation in the central Sichuan paleo-uplift of the Sichuan Basin as examples,this paper explores an effective palethermometer scale combination and method system which can indicate the thermal history of ancient strata in a superimposed basin.It reconstructs the thermal history of the key layers of Sinian-Cambrian in the central Sichuan paleo-uplift by combining the traditional palethermometer scale with the palethermometer scale of lowtemperature thermochronology with different closure temperatures.Then,the thermal evolution characteristics of the strata in different tectonic stages,the thermal effects of main tectonic-thermal events and the controlling effect of paleo-geothermal on the key process of hydrocarbon accumulation are analyzed,and the adaptability and application significance of different palethermometer scales in the reconstruction of thermal history of old strata in a superimposed basin are discussed.And the following research results are obtained.First,the Dengying Formation and the Canglangpu Formation in the Gaoshiti-Moxi area of central Sichuan paleo-uplift mainly experienced two heating stages and two cooling stages.During the two heating stages,the highest paleotemperature of the Dengying Formation was close to 240℃,and that of the Canglangpu Formation was about 200℃in the Gaoshiti-Moxi area of central Sichuan paleo-uplift,where the Emei mantle plume did not have the decisive impact.Second,under the control of paleo-geothermal,the thermal evolution process of the Lower Cambrian source rocks in the Deyang-Anyue rift area,and the burial dissolution peak and hydrocarbon charging and accumulation process of the De

关 键 词：四川盆地 川中古隆起 高石梯—磨溪地区 震旦系—寒武系 叠合盆地 热史反演 古温标 

分 类 号：TE121.1[石油与天然气工程—油气勘探]