Discovery of Paleoproterozoic rapakivi granite on the northern margin of the Yangtze block and its geological significance

作     者：ZHANG LiJuan MA ChangQian WANG LianXun SHE ZhenBing WANG ShiMing 

作者机构：Faculty of Earth Sciences China University ofGeosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources CUG Wuhan 430074 China 

出 版 物：《Chinese Science Bulletin》 (中国科学通报)

年 卷 期：2011年第56卷第3期

页      面：306-318页

核心收录：

学科分类：070903[理学-古生物学与地层学(含：古人类学)] 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 International Cooperation Project of the Ministry of Science and Technology of China (2007DFA21230) the Natural Science Foundation of Hubei Province (2009CDA004) the National Training Foundation of Geological Science Base (J083520) the National Innovation Experiment Program for University Students (1320311009) part of a Higher Education Key Project of Hubei Province (2009108) 

主　　题：环斑花岗岩 古元古代 扬子陆块 地质意义 花岗岩体 构造事件 北缘 地球化学特征 

摘      要：The Huashanguan rapakivi pluton in Zhongxiang,Hubei Province,China,is the first discovered Proterozoic rapakivi pluton in the Yangtze *** on field and petrographical observations,a typical rapakivi texture was found in the northern portion of the Huashanguan granitic *** all the K-feldspar phenocrysts were round to oval in shape and most had plagioclase coatings known as rapakivi *** feldspars and quartz had two or more ***,the Huashanguan rapakivi granites were characterized as having high values of Si,K,Fe,Th,U,La,Ga,Ce,Sm and LREE,low values of Ca,Mg,Sr,Nb,Y and HREE,and a negative Eu *** geochemical characteristics of the Huashanguan granites were concordant with typical rapakivi granites,and had an affinity to A-type ***-ICP-MS U-Pb zircon dating also was *** dating yielded a 207Pb/206Pb weighted mean age of 1851±18 Ma (MSWD =1.2),which represents the age of the pluton *** age of 803±170 Ma at the lower intercept in the concordia diagram corresponds to the age of a later deformation event which affected the pluton,and suggests that the Huashanguan pluton was influenced by Neoproterozoic thermo-tectonic events after its *** discovery of Paleoproterozoic Huashanguan rapakivi granites indicates continental rifting or a post-orogenic extensional event that took place in the Paleoproterozoic in the Yangtze *** events may be related to the breakup of the Paleoproterozoic Columbia supercontinent.