乌克兰地盾中部新乌克兰卡花岗岩年代学、地球化学特征及成因  

Geochronology,geochemistry and genesis of Novoukrainka granite in the central Ukrainian shield

作　　者：王永飞[1] 李宝新[1] 刘晨阳 曹云 马昌威[1] WANG Yongfei;LI Baoxin;LIU Chenyang;CAO Yun;MA Changwei(Sichuan Institute of Nuclear Geology,Chengdu 610053,China)

机构地区：[1]四川省核工业地质调查院,成都610053

出　　处：《世界核地质科学》2020年第3期176-184,共9页World Nuclear Geoscience

基　　金：科技部国家重点研发计划项目“乌克兰中部基洛沃格勒地块深部铀资源勘探关键技术与装备合作研究”(编号:2016YFE0206300)资助。

摘　　要：对出露于基洛沃格勒断裂带西侧的新乌克兰卡岩体开展了锆石U-Pb年代、地球化学及成因研究。该岩体LA-ICP-MS锆石U-Pb法测年结果为2001±5.2 Ma(MSWD=0.63);岩体富碱(ALK=7.59%~9.04%)、富钾(K2O=4.57%~6.16%),稀土元素具轻稀土元素富集型特征,微量元素中富集Rb、Th、Ba、Pb等大离子亲石元素,亏损Nb、Ta、Zr、Hf等元素,为一套钾玄岩-高钾钙碱性系列岩体。Nb/Ta平均值为19.17,Zr/Hf平均值为39.09,具幔源性质;而岩体中微量元素表现出低Sr、Eu和富集Rb、Th的A型花岗岩特点,认为花岗岩来源于地壳部分熔融。本区高钾钙碱性系列岩浆侵入活动是乌克兰中部元古宙期间岩浆事件的组成部分,反映了乌克兰中部区域构造元古宙期间非造山大陆伸展环境。Study on the geochronology,geochemistry and genesis of the zircon U-Pb age were carried out in the Novoukrainka pluton exposed at the west side of the Kilowograd fault zone.The LA-ICPMS zircon U-Pb age is 2001±5.2 Ma(MSWD=0.63).The pluton is rich in alkali(ALK=7.59%~9.04%),potassium(K2O=4.57%~6.16%).The rare earth elements are rich in light REE,the rocks are rich in Rb,Th,Ba,Pb,and depleted in Nb,Ta,Zr,Hf.In geochemistry of Novoukrainka pluton is of shoshonite-high potassium Ca-alkaline series features the average Nb/Ta is 19.17,the average Zr/Hf is 39.09,which are the nature of mantle source,while the trace elements are low in Sr,Eu and high in Rb,Th,which showed the characteristics of A type granite and can be considered that the granite was originated from the partial melting of the crust.The high potassium Ca-alkaline series magmatic intrusions in this area was believed to be part of the Proterozoic magmatic events in central Ukraine,which suggested the non orogenic continental extension environment of the regional structure in central Ukraine during the Proterozoic.

关 键 词：年代学 地球化学 成因 新乌克兰卡花岗岩 乌克兰地盾 

分 类 号：P588.121[天文地球—岩石学] P59[天文地球—地质学]