豫西曹家窑岩体LA-ICP-MS锆石U-Pb定年及地质意义  

LA-ICP-MS zircon U-Pb dating of Caojiayao pluton in west Henan province and the geological significance

作　　者：徐书奎 XU Shukui(Henan First Geological Brigade Co.,Ltd.,Zhengzhou 450000,Henan province,China;Henan Nonferrous Metal Mineral Exploration Engineering Technology Research Center,Zhengzhou 450000,Henan povinve,China)

机构地区：[1]河南省第一地质大队有限公司,郑州450000 [2]河南省有色金属综合勘查工程技术研究中心,郑州450000

出　　处：《地质找矿论丛》2025年第1期93-99,共7页Contributions to Geology and Mineral Resources Research

基　　金：河南省有色金属地质矿产局2018年重点项目(豫色地矿办[2018]30号);河南省有色金属地质矿产局首批科技创新专项资金(揭榜挂帅)项目(豫色地矿文[2021]62号)共同资助

摘　　要：崤山与其毗邻的小秦岭、熊耳山同属华北陆块南缘,是豫西金银多金属矿的重要成矿区和找矿潜力区。崤山区内大面积出露新太古代中酸性侵入岩体,这些岩体的形成时代、地球化学特征等仍未得到深入的研究和探讨。文章对崤山中部曹家窑二长花岗岩体开展锆石LA-ICP-MS U-Pb定年,显示曹家窑二长花岗岩体锆石U-Pb年龄为2444 Ma±31 Ma,地球化学特征显示其测点数据落入Ⅰ型花岗岩系列和埃达克岩区,富集轻稀土,亏损重稀土,轻重稀土分馏明显,w(La)N/w(Yb)N=3.82~30.83,w(Y)=10.2×10^(-6)~11.7×10^(-6),岩石稀土配分曲线右倾。综合分析认为,曹家窑二长花岗岩具埃达克岩属性,属高钾钙碱性同融型花岗岩(Ⅰ型),是新太古代地壳增厚的产物。Xiaoshan area and the adjacent Xiaoqinlinng and Xiongershan areas all belong to the south margin of north China block.The marginal area is an important Au-Ag polymetallic metallogenic and potential propecting area in west Henen province.In Xiaoshan area is exposed large area of Neo-Archean intermediate-acid intrusive rocks and formation time and geochemical characteristics of the intrusive rocks have not been intensively studied and discussed.This paper deals with the problem.LA-ICP-MS zircon U-Pb dating was made on samples from the intrusive rocks and obtained U-Pb age 2444 Ma±31 Ma of Caojiayao monzonitic granite.The analysis data point fall in field of I-type granitic series and adakite.REE are fractionated,LREE enriched,HREE depleted.w(La)N/w(Yb)N=3.82~30.83,w(Y)=10.2×10^(-6)~11.7×10^(-6).REE pattern obliques to right.The data above show that Caojiayao monzonitic granite is characteristic of adakite belonging to high K-Ca-alkaline syntectic granite.It is the product of crustal thickening.

关 键 词：曹家窑岩体 锆石U-PB定年 崤山 豫西 

分 类 号：P588.121[天文地球—岩石学] P597[天文地球—地质学]