研究进展

薛振华等,GEOLOGICAL SOCIETY OF AMERICA BULLETIN,2022

发表时间:2022-04-02来源:ok138太阳集团中国官方网站点击:

全文链接1:https://pubs.geoscienceworld.org/gsa/gsabulletin/article/134/1-2/15/595732/An-intracontinental-orogen-exhumed-by-basement

全文链接2:https://hal-insu.archives-ouvertes.fr/insu-03186417/document


An intracontinental orogen exhumed by basement-slice imbrication in the Longmenshan Thrust Belt of the Eastern Tibetan Plateau

作者:

Xue, ZH (Xue, Zhenhua) [1] , [2] , [3] ;         Lin, W (Lin, Wei) [2] , [4] ;         Chu, Y (Chu, Yang) [2] , [4] ;         Faure, M (Faure, Michel) [3] ;         Chen, Y (Chen, Yan) [3] ;         Ji, WB (Ji, Wenbin) [5] ;         Qiu, HN (Qiu, Huaning) [6]  

(由 Clarivate 提供)
GEOLOGICAL SOCIETY OF AMERICA BULLETIN

 

134  

1-2  

15-38  

DOI

10.1130/B35826.1

出版时间

JAN-FEB 2022

已索引

2022-01-13

文献类型

Article

摘要

The Longmenshan Thrust Belt in Eastern Tibet resulted from a Mesozoic orogeny and Cenozoic reworking. It is generally believed that the Cenozoic tectonics along the Longmenshan Thrust Belt are mostly inherited from the Mesozoic. Reconstructing the Mesozoic tectonics of the Longmenshan Thrust Belt is therefore important for understanding its evolutionary history. On the basis of detailed structural analysis, we recognized a Main Central Boundary that divides the Longmenshan Thrust Belt into a Southeastern Zone and a Northwestern Zone. Both zones underwent a main D-1 event characterized by D-1E top-to-the-SE thrusting in the Southeastern Zone and D-1w top-to-the-NW/N thrusting in the Northwestern Zone. In the Southeastern Zone, a D-2 top-to-the-NW/N normal faulting that cuts the D-1E structures is developed along the NW boundary of the basement complexes. Newly obtained and previous geochronological data indicate that the D-1E and D-1w events occurred synchronously at ca. 224-219 Ma, and the D2 top-to-the-NW/N normal faulting was episodically activated at ca. 166-160 Ma, 141-120 Ma, 81-47 Ma, and 27-25 Ma. Episodic and synchronously activated top-to-the-NW normal faulting and top-to-the-SE thrusting along the northwestern and southeastern boundaries of the basement complexes, respectively, leads us to propose that the basement slices were episodically imbricated to the SE during the Late Jurassic-Early Cretaceous and Late Cretaceous-earliest Paleocene. The D-1w amphibolite facies metamorphic rocks above the basement complexes recorded fast exhumation during the Late Jurassic-Early Cretaceous. We propose that the early Mesozoic northwestward basement underthrusting along a crustal "weak zone" was responsible for the D-1w double-vergent thrusting and amphibolite facies metamorphism. Subsequent basement-slice imbrications reworked the Longmenshan Thrust Belt and exhumed the amphibolite facies rocks. Our results highlight the importance of basement underthrusting and imbrication in the formation and reworking of the intracontinental Longmenshan Thrust Belt in Eastern Tibet.

关键词

 

作者信息

通讯作者地址

Lin, Wei    

(通讯作者)

            Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China    

通讯作者地址

Lin, Wei    

(通讯作者)

            Univ Chinese Acad Sci, Beijing 100049, Peoples R China    

地址

 

电子邮件地址

linwei@mail.iggcas.ac.cn  

类别/分类

研究方向

Geology