Geochemical and Nd-Hf Isotopic Constraints on the Petrogenesis of an Archean Granitoid in the Erguna Massif, NE China  

作　　者：SHAO Jun LI Yinglei WANG Deli SONG Wanbing WU Xinwei LIU Hongzhang 

机构地区：[1]Shenyang Institute of Geology and Mineral Resources,Shenyang Center,China Geological Survey,Shenyang 110034,China [2]Key Laboratory of Orogen and Crust Evolution,Department of Geology,Peking University,Beijing 100871,China [3]Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China [4]Inner Mongolia 115th Geological Mineral Exploration and Development Co.Ltd.,Huhhot 137100,China [5]Inner Mongolia 6th Geological Mineral Exploration and Development Co.Ltd.,Hulunbuir,Inner Mongolia 021008,China [6]Hebei Regional Geological Survey Institute,Hebei 065000,China

出　　处：《Acta Geologica Sinica(English Edition)》2021年第6期2033-2044,共12页地质学报（英文版）

基　　金：financially supported by Geological Survey projects of China Geological Survey (DD20160047 and 12120115031301)。

摘　　要：Crystalline basement and Precambrian crustal growth of the continental massifs within the Central Asian Orogenic Belt(CAOB) are still pending problems. Our geological and geochemical investigations identified an Archean(2606 Ma) granitic pluton in the Biliya area of the Erguna Massif. The Neoarchean granitoids show high and positive in-situ zircon ε_(Ht)(t)(+0.3 to +10.0), whole-rock ε_(Nd)(t)(+4.8) and whole-rock ε_(Ht)(t) values(+2.1). They are characterized by high Y + Ce + Zr + Nb(> 220 ppm) and Zr contents and could be classified as A-type granites. These granitoids are characterized by high Zr saturation temperatures(T;)(796–836°C). They were derived from partial re-melting of juvenile mafic lower crust in an intracontinental back-arc extensional environment. This newly identified Neoarchean granitic pluton may represent the crystalline basement of the several continent massifs within the CAOB, and their high ε_(Ht)(t)–ε_(Nd)(t) values may also indicate the occurrence of lateral crustal growth events in these massifs during the Neoarchean.

关 键 词：crystalline basement A-type granite Neoarchean crustal growth NEOARCHEAN Central Asian Orogenic Belt 

分 类 号：P588.12[天文地球—岩石学] P534.2[天文地球—地质学] P597.3