摘要
内蒙古雅布赖地区位于阿拉善地块北缘,雅布赖—诺日公—红谷尔玉林构造带西端,对该地区辉长岩产出年代、地球化学特征进行研究,结果表明:锆石U-Pb同位素测年结果为(273.2±1.0)Ma,显示其形成于早二叠世晚期,稀土元素配分曲线右倾,轻重稀土分馏较明显,Eu异常不明显(δEu为0.93~1.15);微量元素原始地幔标准化蛛网图中相对富集大离子亲石元素,亏损高场强元素;可能形成于古亚洲洋向南俯冲环境,并在成岩过程中受到了明显的陆壳物质的混染。
Yabulai is located in the western part of Yabulai-Nuorigong-Honggueryulin belts,Northern Alxa block.This study discussed the age and geochemical characteristics of gabbro in the Yabulai area.Zircon U-Pb dating indicates that the gabbro of the Yabulai area were formed in the late Early Permian(273.2±1.0)Ma.Geochemical characteristics shows that the gabbro of the Yabulai area exhibits significant fractionation between LREE and HREE with slight Eu anomaly(0.93<δEu<1.15).A standardized spider diagram of the primitive mantle of trace elements show the relative enrichment of large ion lithophile elements and depletion of high field strength elements.The paper believed that the gabbro of the Yabulai area might have been formed in an active continental margin setting related to the southward subduction of the Paleo-Asian Ocean and it was obviously contaminated by continental crust materials during its diagenesis.
作者
张家兴
王凯垒
Zhang Jiaxing;Wang Kailei(No.519 Geological Team,North China Geological Exploration Bureau,Baoding 071000,Hebei,China)
出处
《地质学刊》
CAS
2021年第1期13-20,共8页
Journal of Geology
基金
中国地质调查局地质调查项目“内蒙古1∶5万塔尔拜呼都格(J48E002004)、白石头(J48E002005)、红柳沟(J48E003004)幅区域地质矿产调查”(DD20160039-13)。
