北秦岭柿树园组变质沉积岩年代学及构造意义
DOI:
作者:
作者单位:

1.河南省地质研究院,地质过程与矿产资源国家重点实验室河南技术联合研发和示范中心,河南省金属矿产成矿地质过程与资源利用重点实验室;2.河南省地质研究院,地质过程与矿产资源国家重点实验室河南技术联合研发和示范中心,河南省金属矿产成矿地质过程与资源利用重点实验室;3.河南省地质研究院河南省地质研究院,地质过程与矿产资源国家重点实验室河南技术联合研发和示范中心,河南省金属矿产成矿地质过程与资源利用重点实验室;4.河南省地质研究院

作者简介:

通讯作者:

中图分类号:

基金项目:


Geochronology of detrital zircons from metaclastic of Shishuyuan Formation in the North Qinling belt and its tectonic implication
Author:
Affiliation:

1.Henan Institute of Geology;2.Henan Key Laboratory For Metallogenetie Process Of Metal Mineral Resource And Resource Utilization

Fund Project:

单位:
  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    柿树园组位于北秦岭造山带,主要由浅变质的砂岩、泥岩组成的一套陆源碎屑深水相复理石沉积。通过LA-MC-ICPMS锆石U-Pb测年研究,柿树园组碎屑锆石年龄为438~3562 Ma,获得一个主要年龄峰值~949 Ma和五个次要年龄峰值~2482 Ma,~1707Ma,~1140 Ma,~839 Ma和~514 Ma。其中最年轻的一组碎屑锆石年龄为438~543Ma,结合柿树园组遭受泥盆纪绿片岩相变质作用及缺少北侧宽坪岩群~414Ma的物质沉积记录,表明其主体沉积时代为中-晚志留世(438~415Ma)。综合区域研究认为,柿树园组是由不同年龄的沉积单元组成,应为一构造地层单位,需进一步解体;沉积物源主要来自所在的北秦岭,次为北侧华北陆块南缘和南侧南秦岭,具双源性特征;其构造环境与宽坪岩群(谢湾岩组)应同属一海盆地,但并非二郎坪群之晚期弧后盆地,可能是中志留世-泥盆纪北秦岭后碰撞阶段伸展背景下形成的一陆缘盆地。

    Abstract:

    The Shishuyuan Formation, located in the North Qinling Orogenic Belt, is a set of terrigenous clastic deep-water flysch deposits composed mainly of slightly metamorphosed sandstone and mudstone. LA-MC-ICPMS zircon U-Pb dating results show that the detrital zircon ages of the Shishuyuan Formation range from 438 to 3562 Ma, with a primary peak at ca. 949 Ma and five secondary peaks at ca. 2482 Ma, ca. 1707 Ma, ca. 1140 Ma, ca. 839 Ma and ca. 514 Ma. The youngest population of detrital zircon ages ranges from 438 to 543 Ma. Combined with the Devonian greenschist-facies metamorphism observed in the formation and the absence of ca. 414 Ma depositional records from the adjacent Kuanping Group to the north, the main depositional age of the Shishuyuan Formation is inferred to be the Middle-Late Silurian (438–415 Ma). Integrated regional studies suggest that the Shishuyuan Formation represents a tectonostratigraphic unit composed of sedimentary subunits of varying ages, which requires further subdivision into distinct units.Provenance analysis indicates that the sediments were primarily derived from the North Qinling Belt, with secondary contributions from the southern margin of the North China Block and the South Qinling Belt, characterized by a dual provenance. The tectonic setting of the Shishuyuan Formation and the Kuanping Group (Xiewan Formation) is inferred to represent a shared marine basin. However, unlike the late back-arc basin of the Erlangping Group, this basin is interpreted as a continental margin basin formed during Middle Silurian to Devonian post-collisional extension in the North Qinling Orogenic Belt.

    参考文献
    相似文献
    引证文献
引用本文
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2024-12-16
  • 最后修改日期:2025-02-25
  • 录用日期:2025-03-13
  • 在线发布日期:
  • 出版日期: