Neoarchean Magmatic Events in the Western Songnen Massif,Central Asian Orogenic Belt:Timing and Tectonic Significance  

作　　者：WU Xinwei LIU Zhenghong LIU Yongjiang ZHANG Chao SHAO Jun ZHANG Chao ZHANG Yujin GUO Wei LIU Baoshan ZHANG Guangyu 

机构地区：[1]Shenyang Center of China Geological Survey,Shenyang 110034,China [2]Key Laboratory of Deep Mineral Resources Exploration and Evaluation,Department of Natural Resource of Liaoning Province,Shenyang 110034,China [3]College of Earth Sciences,Jilin University,Changchun 130061,China [4]Frontiers Science Center for Deep Ocean Multispheres and Earth System,Key Laboratory of Submarine Geosciences and Prospecting Techniques,MOE and College of Marine Geosciences,Ocean University of China,Qingdao,Shandong 266100,China [5]Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao Shandong 266100,China [6]School of Resources and Environmental Engineering,Shandong University of Technology,Zibo,Shandong 255049,China

出　　处：《Acta Geologica Sinica(English Edition)》2023年第2期436-448,共13页地质学报（英文版）

基　　金：co-supported by the National Key R&D Program of China(Grant No.42130305);China Geological Survey(Grant Nos.DD20221687,DD20230047,DD20160047);the NSFC project(Grant Nos.41802238,42102271)。

摘　　要：Whether a Neoarchean basement existing in the Songnen massif is currently debated.Identification of Archean magmatism from the Songnen Massif is helpful to resolve this issue.Here,we report newly discovered Neoarchean Shanquan pluton in the Western Songnen Massif.These Neoarchean Shanquan pluton are mainly composed of granites that are exposed near the town of Shanquan in Heilongjiang Province.LA-ICP-MS zircon U-Pb dating reveals that the sample 2015TW1 has an upper intercept age of 2801±69 Ma and a weighted mean age of 2708±18 Ma,while samples LJ27QY1 and LJ27QY2 have upper intercept ages of 2677±57 Ma and 2653±18 Ma,and weighted mean ages of 2649±10 Ma and 2653±15 Ma,respectively.This indicates that these granites were formed at~2.7 Ga.Most of the~2.7 Ga zircons have older TDM2 ages of 2762–3326 Ma with positiveεHf(t)values ranging from 0 to 6.4,while a few of the zircons have negativeεHf(t)values ranging from-8.1 to-11.5 and older TDM2 ages varying from 3158 to 3264 Ma.The zircon Hf isotopes indicate that Paleo-Mesoarchean crusts might once existed in the Songnen Massif,and the studied Neoarchean magmas were principally derived from partial melting of these Paleo-Mesoarchean ancient crust.Based on the geochronological spectrum of magmatic and detrital zircons,the Songnen,Erguna,Jiamusi,Bureya massifs may have a common basement prior to the Neoproterozoic and may even be linked with the Triam Craton.

关 键 词：tectonic attribute Neoarchean magmatism Precambrian basement Longjiang area Songnen Massif 

分 类 号：P534.2[天文地球—古生物学与地层学] P588.11[天文地球—地质学]