Coherent Chemical Variation Trends of the 55-25 Ma Magmatic Rocks in SE Tibet:N-S Direction Lithospheric Stretching of Eurasia during Early Stage of India-Eurasia Collision

作     者：YANG Tiannan DONG Mengmeng XUE Chuandong XIN Di LIANG Mingjuan YANG Tiannan;DONG Mengmeng;XUE Chuandong;XIN Di;LIANG Mingjuan

作者机构：Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Chinese MNR Laboratory of Deep Earth Sciences and TechnologyBeijing 100037China Department of Earth SciencesKunming University of Science and TechnologyKunming 650093China Geological Museum of GuizhouGuiyang 550081China 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：2023年第97卷第5期

页      面：1283-1305页

核心收录：

学科分类：070904[理学-构造地质学] 0709[理学-地质学] 070901[理学-矿物学、岩石学、矿床学] 07[理学] 

基　　金：supported by the Ministry of Sciences and Technology of China(Grant No.2022YFF0800901) the Natural Science Foundation of China(Grant No.92055206) 

主　　题：tectonics geochemistry magmatic zone temporal/spatial distribution lithospheric stretch Eocene to Oligocene SE Tibet 

摘      要：The progressive indentation of India into Eurasia generated an E-W-trending orthogonal collision belt and a N-S-trending oblique collision *** available data reveals that~70%of the Cenozoic igneous rocks in eastern and southeastern Tibet are concentrated within an ENE-trending,~550-km long and~250-km wide magmatic zone(CMZ)that once separated the orthogonal and oblique collision *** Latitude 26°N Line is now its southern *** onset timing of magmatism of the CMZ varies gradually from~55 Ma in the westernmost part to~27 Ma in the *** the magmatism successively occurred and suddenly stopped at~25 *** segmented and coherent chemical variation trends found suggest that the CMZ magmatic rocks were formed due to partial melting of the heterogeneous upper mantle and crusts of *** of Paleo-and Neotethyan oceanic plates generated this compositional and mineralogical *** with available geophysical data,the CMZ was diachronously formed in response to asthenosphere upwelling induced by NNW-SSE-direction lithosphere *** difference in responses of the orthogonal and oblique collision belts to the indentation of the Indian continent has led to this lithosphere stretching.