矿床地质2017，Vol.36Issue(1)：158-170,13.DOI:10.16111/j.0258-7106.2017.01.010
北祁连浪力克地区毛藏花岗闪长岩年代学、Hf同位素及地球化学特征
Geochronology, Hf isotopic and geochemical characteristics of Maozang granodiorite in Langlike area, North Qilian Mountain
摘要
Abstract
The granodiorite pluton in Langlike area of Menyuan,Qinghai,is located in the eastern Lenglongling of North Qilian Mountain.The authors conducted a study of chronology and geochemistry to constrain its geochronology and petrogenesis.Zircon LA-ICP-MS dating yielded a concordant age of (471.9 ± 8.6)Ma (MSWD=1.6),suggesting Ordovician in Early Paleozoic.Zircon Hf isotope analysis suggests that the calc-alkaline units have TDM2 values between 1112.4 and 2284.7 Ma,with εHf(t) values from-13.3 to 5.26,indicating that the magma sources were involved in crust-mantle mixing,the source region of the crust type was likely to be ancient crustal rocks of Paleoproterozoic and Mesoproterozoic.In addition,rock geochemistry indicates that the rock is a weak peraluminous potassium calc-alkaline series of Ⅰ-type granites,obviously enriched in LILE (such as K,Ba,Rb) and incompatible elements such as Th and U,and relatively depleted in high field strength elements such as Nb,Ta,Ti and P,implying a volcanic arc granite formed in a subduction environment.关键词
地球化学/中钾钙碱性侵入岩/岩石成因/锆石U-Pb年龄/北祁连毛藏Key words
geochemistry/potassium calc-alkaline intrusive rock/petrogenesis/zircon U-Pb age/Maozang area of North Qilian Mountain分类
天文与地球科学引用本文复制引用
白赟,郭周平,赵辛敏..北祁连浪力克地区毛藏花岗闪长岩年代学、Hf同位素及地球化学特征[J].矿床地质,2017,36(1):158-170,13.基金项目
本文受中国地质调查局“青海门源县银灿-浪力克1∶5万成矿预测”项目(编号:1212011221043)和“青海门源县宁缠河-牛头山一带铜多金属矿调查评价”项目(编号:12120115022401)资助 （编号:1212011221043）
