摘要
四川盆地西北缘上三叠统多源—汇体系导致盆内砂泥岩展布规律复杂多变。为定量追索上三叠统须家河组源—汇体系,开展碎屑锆石磷灰石裂变径迹年代学和盆缘造山带物源区构造年代学编图对比分析,建立了四川盆地西北缘晚三叠世多源—汇体系构造年代学多期响应模式。结果表明:①川西北地区工农镇和汉旺须家河组露头剖面碎屑锆石裂变径迹年龄为143~226 Ma,分异系数为15%~35%,220余颗单颗粒碎屑锆石裂变径迹年龄大部分大于其沉积地层年龄,反映不同物源区构造变形与抬升剥蚀特征;②碎屑锆石裂变径迹峰值年龄集中为325±16 Ma、228±11 Ma、213±16 Ma、196±15 Ma,分别代表了物源区石炭纪和中—晚三叠世3期构造抬升剥蚀事件;③晚三叠世3个裂变径迹年龄峰值分别对应了盆地北缘大巴山—武当古陆、米仓山—汉南古陆、摩天岭古陆和松潘—甘孜地区的晚三叠世印支期早幕(约230 Ma)、印支期中幕(约210 Ma)和印支期晚幕200 Ma构造抬升剥蚀事件。因此,四川盆地西北缘晚三叠世多源—汇体系具有明显的构造年代学和沉积响应特征,体现出由北向南渐进式盆山系统构造—沉积耦合特点。
The Triassic multi-source-sink system on the northwest margin of the Sichuan Basin leads to complex and changeable distribution of sandstone and mudstone in the basin.In order to quantitatively trace the sourcesink system of the Upper Triassic Xujiahe Formation,a comparative analysis of clastic zircon apatite fission track chronology and tectonic chronology of provenance areas in basin margin orogenic belts has been carried out,and a multi stage response model of Late Triassic multi-source-sink system tectonic chronology in the northern margin of Sichuan Basin has been established.The results show that:(1)The age of clastic zircon fission trails in the outcrop profile of Gongnong Town and Hanwang Xujiahe Formation in northern Sichuan is 143-226 Ma,the differentiation coefficient is 15%-35%,and most of the age of more than 220 single-grain zircon fission trails is greater than the age of their sedimentary strata,reflecting the characteristics of tectonic deformation and uplift and ablation in different source areas.(2)The peak age of clastic zircon fission trails was concentrated as follows:325±16 Ma,228±11 Ma,213±16 Ma,196±15 Ma,representing the Carboniferous and Middle-Late Triassic tertiary tectonic uplift and ablation events in the source area,respectively.(3)The age peaks of the three fission trails of the Late Triassic correspond to the Late Triassic Early Indochina Period(about 230 Ma),Meso-Indochinese Period(about 210 Ma)and Late Indochin Period(200 Ma)in the northern margin of the basin.Therefore,the Late Triassic multi-source-sink system in the northern margin of the Sichuan Basin has obvious tectonic chronology and sedimentary response characteristics,reflecting the coupling characteristics of tectonic-sedimentary coupling of the progressive basin-mountain system from north to south.
作者
曹正林
邓宾
胡欣
杨荣军
徐宏远
刘重江
邱玉超
郑超
芦刚
刘四兵
CAO Zhenglin;DENG Bin;HU Xin;YANG Rongjun;XU Hongyuan;LIU Chongjiang;QIU Yuchao;ZHENG Chao;LU Gang;LIU Sibing(Research Center of Sichuan Basin,PetroChina Research Institute of Petroleum Exploration and Development,Chengdu 610094,China;Research Institute of Exploration and Development,PetroChina Southwest Oil&Gasfield Company,Chengdu 610041,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;Northwest Sichuan Gas Mine of Southwest Oil and Gasfield Branch,Jiangyou 621700,China)
出处
《天然气地球科学》
CAS
CSCD
北大核心
2023年第11期1871-1886,共16页
Natural Gas Geoscience
基金
国家自然科学基金(编号:41402119,2014JQ0057,41472107,41230313)
中国石油天然气股份有限公司科学研究与技术开发项目(编号:2021DJ0204)联合资助.
关键词
构造年代学
源—汇体系
晚三叠世
印支期
川西北地区
Tectonic chronology
Source-sink system
Late Triassic
Indosinica Period
Northwest Sichuan Basin
作者简介
曹正林(1970-),男,重庆人,博士,教授级高级工程师,主要从事沉积盆地评价技术研究.E-mail:caozl@petrochina.com.cn;通信作者:邓宾(1980-),男,四川南充人,博士,教授,主要从事含油气盆地分析与油气成藏研究.E-mail:dengbin13@mail.cdut.edu.cn.
