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现代地质 ›› 2025, Vol. 39 ›› Issue (03): 728-751.DOI: 10.19657/j.geoscience.1000-8527.2024.112

• 机器学习与矿物学应用 • 上一篇    下一篇

华北克拉通中部菅等岩体的成因及构造意义: 锆石U-Pb年代学、岩石地球化学的约束

吴晓贺1,2(), 张聚全1,2,*(), 段站站1,2, 张乐民1,2, 温雨菁1,2, 郭子桤1,2, 李清1,2   

  1. 1.河北地质大学河北省战略性关键矿产资源重点实验室,河北 石家庄 050031
    2.河北地质大学地球科学学院,河北 石家庄 050031
  • 出版日期:2025-06-10 发布日期:2025-07-03
  • 通信作者: *张聚全,男,博士研究生,教授,1983年出生,主要从事成因矿物学、矿床学研究工作。Email:juquan1983@163.com
  • 作者简介:吴晓贺,女,在读研究生,1998年出生,主要从事成因矿物学研究工作。Email:811209713@qq.com
  • 基金资助:
    河北省自然科学基金项目(2021403028);河北地质矿产勘查开发科研基金项目(13000022P0032910103R);河北地质大学第二十届学生科研基金项目(KAY202402);河北省自然资源厅地勘项目(13000022P00F2D4101216);河北省自然资源厅地勘项目(13000023P00F2D410251H);河北地震局震防中心项目(HBHY(2023)-02-38)

The Genesis and Tectonic Significance of Jiandeng Intrusive Rock in the Central North China Craton: Constraints from Zircon U-Pb Chronology and Petrogeochemistry

WU Xiaohe1,2(), ZHANG Juquan1,2,*(), DUAN Zhanzhan1,2, ZHANG Lemin1,2, WEN Yujing1,2, GUO Ziqi1,2, LI Qing1,2   

  1. 1. Hebei Key Laboratory of Strategic Critical Mineral Resources, Hebei GEO University, Shijiazhuang, Hebei 050031, China
    2. College of Earth Science, Hebei GEO University Shijiazhuang, Hebei 050031, China
  • Published:2025-06-10 Online:2025-07-03

摘要: 准确约束华北克拉通基底形成和变质变形年龄,是理解华北克拉通早期构造演化的关键。菅等岩体位于华北克拉通中部造山带的东南段赞皇杂岩中,为~2.5 Ga花岗岩,并经历多期变质和变形。本文对菅等岩体及侵入岩体内部的未变形伟晶岩、粗粒变形花岗岩脉、细粒变形花岗岩脉、花岗质岩株进行了系统的野外调查、岩相学、岩石地球化学、锆石U-Pb年代学研究。结果表明:菅等岩体主体岩性为正长花岗岩,未变形伟晶岩岩性为二长花岗伟晶岩,粗粒变形花岗岩脉、细粒变形花岗岩脉、花岗质岩株均为正长花岗岩;菅等岩体及其内部的侵入体具有高Si,富K,富碱,低Ti、Fe、Mg,贫Ca,富集大离子亲石元素Rb,亏损高场强元素Ti的特征,且Rb/Sr=0.75~1.56,显示出壳源特征;岩石具有的高Al低Ti特征,以及岩浆锆石高Pb低Th,均指示菅等岩体为过铝质S型花岗岩类型;对锆石进行LA-ICP-MS测定显示存在~2.5 Ga、~2.3 Ga两期的花岗岩侵入事件,岩体内部侵入活动分为三期,分别形成于~2.5 Ga、~2.3 Ga、~2.1 Ga,其中细粒变形花岗岩脉中保留了1897±17 Ma的变质事件的记录。华北克拉通的构造演化由多期次岩浆侵入与变质事件共同驱动。~2.5 Ga的菅等岩体形成标志克拉通形成统一基底,指示早期构造稳定化过程。古元古代两期花岗岩侵入(2.3 Ga和2.1 Ga)揭示克拉通内部发生裂解-伸展事件,~1.85 Ga的变质事件代表东部与西部陆块之间的俯冲碰撞过程。

关键词: 菅等岩体, S型花岗岩, 岩石地球化学, 华北克拉通

Abstract:

Accurately constraining the basement formation and metamorphic deformation age of the North China Craton is the key to understanding the early tectonic evolution of the North China Craton. The Jiandeng intrusion is located in the Zanhuang complex in the southeast member of the central orogenic belt of the North China Craton, which is ~2.5 Ga granite and has undergone multi-stage metamorphism and deformation. A detailed multidisciplinary study on Jiandeng intrusion and associated undeformed pegmatites, coarse-grained deformed granite, fine-grained deformed granite,and granitic stock within Jiandeng intrusion includes field investigation, petrography, petrogeochemistry, and zircon U-Pb chronology. The results show that the main lithologies are gneiss syenogranite and monzogranite pegmatite for undeformed pegmatites. The lithologies of the other three intrusions are syenogranite. The geochemical characteristics of jiandeng intrusion and veins show high Si, rich in K and alkali elements contents, low Ti, Fe, Mg and Ca content, and rich in large ion lithophilic element Rb but deficient in high field strength element Ti. The Rb/Sr ratio ranges from 0.75 to 1.56, indicating crustal source characteristics. High Al and low Ti, and high Pb and low Th in magmatic zircon, further indicate that the Jiandeng intrusion belong to peraluminous S-type granite. LA-ICP-MS dating of zircon shows that there are ~2.5 Ga and ~2.3 Ga granite magmatic events. Veins magmatic activity can be divided into three stages, with the first three stages formed at ~2.5 Ga, ~2.3 Ga, and ~2.1 Ga, respectively. The fine-grained deformed granite records a metamorphic event at 1897±17 Ma. The tectonic evolution of the North China Craton is driven by a combination of multi-stage magmatic intrusions and metamorphic events. The formation of the Jiandeng intrusion at ~2.5 Ga marks the formation of a unified basement, indicating an early tectonic stabilization process. The Paleoproterozoic granite intrusions (2.3 Ga and 2.1 Ga) revealed a cracking-extensional event within the craton, and the metamorphic event of ~1.85 Ga represented a subduction collision process between the eastern and western land masses.

Key words: Jiandeng intrusion, S-type granite, petrogeochemistry, North China craton

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