桂北元宝山新元古代花岗岩锆石U-Pb年代学及地质意义  

ZIRCON U-PB CHRONOLOGY AND GEOLOGICAL SIGNIFICANCE OF THE NEOPROTEROZOIC GRANITE IN YUANBAOSHAN,NORTHERN GUANGXI

作　　者：马文富 吕昶良 杨宝丁 赵兵 胡旭刚 MA Wen-fu;LV Chang-liang;YANG Bao-ding;ZHAO Bing;HU Xu-gang(Geophysical Survey Institute of Guangxi Zhuang Autonomous Region,Liuzhou 545005;Geological Survey Institute of Guangxi Zhuang Autonomous Region,Nanning 530023;Guangxi mineral resources reserve evaluation center,Nanning 530028,Guangxi)

机构地区：[1]广西壮族自治区地球物理勘察院,广西柳州545005 [2]广西壮族自治区地质调查院,广西南宁530023 [3]广西矿产资源储量评审中心,广西南宁530028

出　　处：《云南地质》2023年第4期431-441,共11页Yunnan Geology

摘　　要：通过LA-MC-ICP-MS锆石U-Pb年龄测定,桂北元宝山花岗岩体内细粒斑状黑云花岗岩、粗粒斑状黑云花岗岩、细粒黑云花岗岩成岩年龄分别为823±5.6Ma、820±9.5Ma、813±6.5Ma,属新元古代四堡晚期。基于岩体地质特征及不同侵入体之间的侵入接触关系,认为元宝山花岗岩体至少可划分3个侵位期次。扬子陆块和华夏陆块拼合时间上限限定在813Ma左右。Through LA-MC-ICP-MS zircon U-Pb dating,the diagenetic ages of fine-grained porphyritic biotite granite,coarse-grained porphyritic biotite granite and fine-grained biotite granite in the Yuanbaoshan granite body in northern Guangxi are 823±5.6Ma,820±9.5Ma and 813±6.5Ma,respectively,belonging to the late Neoproterozoic Sibao period.Based on the geological characteristics of the rock mass and the intrusion contact relationship between different intrusive bodies,the authorproposes that the Yuanbaoshan granite body can be divided into at least three emplacement periods,andtheupper limit of the combination of the Yangtze and Huaxia blocks is limited to around 813 Ma.

关 键 词：花岗岩体 锆石U-PB 地质意义 元宝山 广西融水县 

分 类 号：P597.3[天文地球—地球化学]