措勤盆地冈底斯构造带侵入岩岩石地球化学特征及构造成因分析

宋全友; 秦勇

措勤盆地冈底斯构造带侵入岩岩石地球化学特征及构造成因分析

宋全友,
秦勇

中国矿业大学, 江苏徐州 221008

基金项目: 中国石油天然气集团公司青藏项目(CQ95YZ1-0102CQ96YZ2-0102)部分成果

收稿日期: 2001-07-12

修回日期: 2002-01-14

刊出日期: 2002-09-15

Petrogeochemical characteristics and tectonic origin of intrusive rocks in Gangdese tectonic belt of Cuoqin basin, Tibet

China Mining University, Jiangsu Xuzhou, 221008, China

Received Date: 12 July 2001

Revised Date: 14 January 2002

Publish Date: 15 September 2002

摘要

摘要: 冈底斯构造带为措勤盆地一主要级构造单元。该带中、新生代岩浆活动异常强烈,形成从中性闪长岩到酸性花岗岩完整的中酸性花岗岩侵入岩带。通过对侵入岩体的岩石类型、岩石化学特征、岩石地球化学特征研究,认为该岩浆岩带侵入岩体主要为花岗闪长岩、二长花岗岩、石英二长岩等,属钙碱性岩石系列,具“Ⅰ”型花岗岩的特征,是新特提斯洋壳沿雅鲁藏布江断裂带向北俯冲引起下地壳物质熔融向上侵入所致,为燕山晚期-喜山早期岩浆活动的产物。
- 冈底斯构造带 /
- 岩石化学 /
- 侵入体 /
- 构造环境
Abstract: Gangdese tectonic belt is a major one in Cuoqin basin, in which the magmatic action was very strong in the periord of Mesozoic and Cenozoic era. This study shows it belongs to a complete intrusive rocks belt from intermediate diorite to acid granite. The study on the rock types, petrochemical characteristics and petogeochemical characteristics of the intrusive rocks reveals that its rock types are dominated by granodiorite, adamellite and quartz monzonite which belong to calc-alkalic rock series and have the characteristics of "Ⅰ" granite.They are the products of lower crustal matter melting and upt ruding caused by the northward subduction of the New-Tethyan crust along the Yarlung Fracture in the late Yanshanian period.
- Gangdese tectonic belt /
- petrochemistry /
- intrusive /
- tectonic environment