地质通报2012，Vol.31Issue(5)：662-670,9.
内蒙古西部阿拉善地区哈里努登花岗岩LA-ICP-MS锆石U-Pb年龄和地球化学特征
LA-ICP-MS zircon U-Pb age and geochemistry of the Early Permian Halinudeng granite in northern Alxa area, western Inner Mongolia
摘要
Abstract
The Halinudeng pluton is located in the northern margin of Alxa area. LA-ICP-MS U-Pb dating of zircons from the plu-ton yields an age of 284.0± 1.8 Ma , indicating that the formation of this pluton is Permian instead of Silurian as previous considered. The main rock types of the pluton include biotue-plagioclase granites and biotite monzogranites. with high SiO2 (67%-72%), CaO (2.2%-4.4%) and Al2O3 (14.5%-17.2%). Geochemical characteristics indicate that they are metahuminous-weakly peraluminous (A/ CNK=0.90-1.07) and calc-alkaline to high-K calc-alkahne rocks (Na2O)=3.7%-4.3%,K2O=2.1%-2.9%), assuming characteristics of 1-type granite. The rocks have lower REE contents (35.2 × 10-6-130.6 × 10-6) with relative enrichment of LREE and positive Eu anomaly (δEu= 1.04-1.90). The primitive mantle normalized trace element patterns are characterized by the enrichment of the LILE(K, Rb, Ba, Sr) and depiction of the HFSE (Ta, Nb, P, Yb, Y) , showing the features of arc granites. It is considered that the northern margin of Alxa might still have had some arc-related magmatic activities during the Early Permian period.关键词
阿拉善地区/二叠纪/花岗岩/锆石U-Pb年龄/弧Key words
Alxa area/ Permian/ granite/LA-ICP-MS zircon U-Pb dating/ arc分类
天文与地球科学引用本文复制引用
史兴俊,童英,王涛,张建军,张招崇,张磊,郭磊,曾涛,耿建珍..内蒙古西部阿拉善地区哈里努登花岗岩LA-ICP-MS锆石U-Pb年龄和地球化学特征[J].地质通报,2012,31(5):662-670,9.基金项目
中国地质调查局项目《中国和亚洲不同造山带花岗岩》(编号:1212010611803)、《全国地质志》(编号:1212010811033)和国家自然科学基金项目《阿尔泰南缘晚古生代两期碱性花岗岩时空分布、成因特点及构造意义》(批准号:40702010) （编号:1212010611803）
