摘要
为了重建四川盆地北缘五峰组和龙马溪组沉积构造格局,以四川盆地北缘米仓山-大巴山地区五峰组和龙马溪组为研究对象,进行地层格架对比和沉积相分析,并使用Mo/TOC和Al-Co[EF]×Mn[EF]地球化学指标对沉积时期水体滞留程度进行判识.发现靠近隆起区,受物源供给及沉积空间控制,地层厚度差异较大,黑色页岩厚度整体较小.而远离隆起区,受大陆边缘上升洋流和陆内凹陷控制,黑色页岩自西向东逐渐加厚,TOC含量增高.研究表明:(1)米仓山地区五峰组沉积时期南郑福成和南江桥亭位于两种上升洋流交汇区域,长期受上升洋流影响;龙马溪组沉积时期主要受西乡上升影响,导致旺苍和南江地区隆升成岛,MS1井沉积最厚.(2)大巴山前缘及鄂西-渝东地区五峰组整体呈现出隆-凹相间的格局;受到来自华夏地块自南东至北西的持续挤压,龙马溪组沉积时期石柱-巫溪一线持续沉降,地层沉积较厚.
In order to reconstruct the sedimentary tectonic pattern of Wufeng Formation and Longmaxi Formation in the northern margin of Sichuan Basin,the Wufeng Formation and Longmaxi Formation in the Micangshan-Dabashan area of the northern margin of Sichuan Basin were taken as the research objects.The stratigraphic framework correlation and sedimentary facies analysis were carried out,and Mo/TOC and Al-Co[EF]×Mn[EF]geochemical indicators were used to determine the degree of water mass restricted in the sedimentary period.It is found that near the uplift area,controlled by the material supply and sedimentary space,the thickness of strata varies greatly,and the thickness of black shale is smaller as a whole.However,far away from the uplift area,the black shale gradually thickens from west to east and the TOC content increases under the control of the upwelling at the continental margin and intracontinental depression.Research shows that:(1)The Wufeng Formation in Micangshan area was deposited in Fucheng of Nanzheng County,and Qiaoting of Nanjiang County,in the intersection area of two kinds of upwelling currents,which were influenced by the upwelling currents for a long time.The sedimentary period of Longmaxi Formation was mainly influenced by the Xixiang Rise,which resulted in the uplift of Wangcang and Nanjiang areas into islands,with the thickest deposition in Well Mashen 1.(2)Generally,the Wufeng Formation in the Dabashan front and the western Hubeieastern Chongqing area presents a pattern of uplift-depression alternation.Due to the continuous compression of the Cathaysian block from SE to NW,the Shizhu-Wuxi line subsided continuously during the sedimentary period of the Longmaxi Formation,resulting in a relatively thick stratigraphic deposition.
作者
肖斌
刘树根
冉波
李智武
叶玥豪
韩雨樾
Xiao Bin;Liu Shugen;Ran Bo;Li Zhiwu;Ye Yuehao;Han Yuyue(Mining Institute of Liaoning Technical University,Fuxin 123032,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China;School of Energy and Power Engineering,Xihua University,Chengdu 610039,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2021年第7期2449-2465,共17页
Earth Science
基金
十三五国家重大专项项目(No.2017ZX05005003-007)
国家自然科学基金资助项目(No.41602153)。
关键词
五峰组
龙马溪组
上升洋流
沉积构造格局
四川盆地
构造地质
Wufeng Formation
Longmaxi Formation
upwelling currents
sedimentary tectonic pattern
Sichuan Basin
tectonics
