成果归属作者：

王根厚

成果归属机构：

地球科学与资源学院

作者：

Zhang, Shanming ; Guo, Xiangguo ; Hu, Erhong ; Kang, Jianfei ; Wang, Genhou ; Xu, Lei ; Fan, Lixin

单位：

Inner Mongolia Univ Technol, Inner Mongolia Engn Res Ctr Geol Technol & Geotech, Sch Resources & Environm Engn, Hohhot 010051, Peoples R China;China Univ Geosci Beijing, Sch Earth Sci & Resources, Beijing 100083, Peoples R China;Inner Mongolia Min Dev Co Ltd, Hohhot 010011, Peoples R China;Inner Mongolia Key Lab Magmat Mineralizat & Ore Pr, Hohhot 010020, Peoples R China;Geol Survey Res Inst Inner Mongolia Autonomous Reg, Hohhot 010020, Peoples R China;Chinese Acad Geol Sci, Inst Geol, Beijing 100037, Peoples R China;Inner Mongolia Agr Univ, Coll Water Conservancy & Civil Engn, Hohhot 010018, Peoples R China;Winning Consortium Simandou SAU, Bp 2162, Conakry, Guinea

关键词：

A-TYPE GRANITES; U-PB ZIRCON; TRACE-ELEMENT; VOLCANIC-ROCKS; NOVA-SCOTIA; JACK HILLS; NB; CONSTRAINTS; EVOLUTION; TA

摘要：

The Weiboshan (Li-, Cs- and Ta-enriched) LCT-type Nb-Ta deposit located in Ejin Banner, Inner Mongolia, represents a newly discovered pegmatite-type rare metal deposit of significant interest. In this paper, we describe the petrography and present new mineralogical and whole-rock geochemical data and zircon U-Pb ages of orerelated granitic pegmatites in this deposit. Pegmatite dikes can be divided into three distinct zones on the basis of their contents: the K-feldspar graphic granite pegmatite zone (Kf), microcline graphic granite pegmatite zone (Mic), and albite-muscovite granite pegmatite zone (Ab). The pegmatite dikes and associated mineralization formed during the Mesozoic. Granite pegmatites in various zones display distinctive geochemical features characterized by high silicon contents, substantial alkali enrichment, and relatively low iron, calcium, and magnesium levels. These pegmatites are classified as peraluminous or quasialuminous and exhibit low total rare earth element concentrations. Notably, these pegmatites are enriched in large ion lithophile elements (LILEs), such as Rb, K, and U, but depleted in high field strength elements (HFSEs), such as P and Ti. The progression from the Kf to Mic to Ab zones signifies the thorough evolution of the granitic magma, where the late-stage nearhydrothermal system assumed a crucial role in the mineralization of rare metals during magma differentiation. The Weiboshan pegmatites, which exhibit syncollisional attributes, are A-type granites formed through crustal partial melting induced by decompression. This process occurred against the background of postorogenic extension driven by asthenospheric mantle upwelling resulting from lithospheric delamination due to crustal collision and thickening.

基金：

China Postdoctoral Science Foundation [2024MD753947]; Scientific Research Project for Universities in Inner Mongolia [NJZZ23084]; Inner Mongolia Natural Science Foundation [2023LHMS04014, 2021LHBS04002]; Basic Research Funds for Universities in Inner Mongolia [JY20240028, JY20220142]

语种：

英文

DOI：

10.1016/j.jseaes.2024.106339

来源：

JOURNAL OF ASIAN EARTH SCIENCES,2024():.

出版日期：

2024-12

提交日期：

2024-11-19

引用参考：

Zhang, Shanming; Guo, Xiangguo; Hu, Erhong; Kang, Jianfei; Wang, Genhou; Xu, Lei; Fan, Lixin. Petrogenesis and tectonic setting of granitic pegmatites in the Beishan orogenic Belt, Northwest China: Evidence from geology, geochronology and geochemistry[J]. JOURNAL OF ASIAN EARTH SCIENCES,2024():.