东昆仑造山带埃坑德勒斯特地区花岗闪长岩的地球化学特征
Geochemical characteristics of granodiorite in Aikengdelesite area in East Kunlun orogenic belt
王琳1
作者信息
- 1. 吉林省地质科学研究所,长春 130012
- 折叠
摘要
为探究青海省东昆仑造山带埃坑德勒斯特地区花岗闪长岩形成的构造环境和动力学背景,对其进行了锆石U-Pb同位素分析及全岩岩石地球化学测试.测试结果表明:该岩体的加权平均年龄为(232.4±1.9)Ma(MSWD =0.58),形成于晚三叠世;在地球化学特征上,它们属于钙碱性系列,A/CNK值介于0.94～0.96 之间,属准铝质,并且明显富集大离子亲石元素,相对亏损高场强元素,该岩体为部分熔融下地壳岩石形成原始岩浆经分离结晶形成的I型花岗岩;综合区域构造背景,认为该花岗闪长岩形成于区域上后碰撞伸展环境,这种伸展环境也为东昆仑地区大量的晚三叠世矿床提供了条件.
Abstract
This paper aims to explore the tectonic environment and dynamic background formed by the granodiorite in Aikengdelesite area of East Kunlun orogenic belt in Qinghai Province,and conducts the zircon U-Pb isotope analysis and the whole rock geochemical testing.The test results indicate that the weighted average age of the granodiorite is(232.4±1.9)Ma(MSWD =0.58),formed in Late Trias-sic.Geochemically;and they belong to the calcium-alkaline series,sub-aluminous granite,with A/CNK values ranging from 0.94 to 0.96,which is significantly enriched with large ion lithophile elements,but relatively depleted in high field strength elements.This rock mass is an I-type granite formed by partial melting of lower crustal rocks into primitive magmaseparated and crystallized;based on the regional tec-tonic background,the author believes that this granodiorite should be formed in the background of region-al post-collision extension,which also provides conditions for a large number of the Late Triassic ore de-posits in the East Kunlun region.
关键词
花岗闪长岩/晚三叠世/地球化学/埃坑德勒斯特/东昆仑Key words
granodiorite/Late Triassic/geochemical/Aikengdelesite/East Kunlun引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据