|本期目录/Table of Contents|

[1]国显正,贾群子,钱兵,等.东昆仑高压变质带榴辉岩和榴闪岩地球化学特征及形成动力学背景[J].地球科学与环境学报,2017,39(06):735-750.
　GUO Xian-zheng,JIA Qun-zi,QIAN Bing,et al.Geochemical Characteristics of Eclogites and Garnet-amphibolites in East Kunlun High Pressure Metamorphic Belt and Their Geodynamic Setting[J].Journal of Earth Sciences and Environment,2017,39(06):735-750.
点击复制

东昆仑高压变质带榴辉岩和榴闪岩地球化学特征及形成动力学背景(PDF)
分享到：

《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]

卷:
第39卷
期数:
2017年第06期
页码:
735-750
栏目:
基础地质与矿产地质
出版日期:
2017-11-15

文章信息/Info

Title:
Geochemical Characteristics of Eclogites and Garnet-amphibolites in East Kunlun High Pressure Metamorphic Belt and Their Geodynamic Setting
文章编号:
1672-6561(2017)06-0735-16
作者:
国显正; 贾群子; 钱兵; 弥佳茹; 李金超; 孔会磊; 姚学钢
1.中国地质调查局西安地质调查中心，陕西 西安 710054； 2.中国地质大学(武汉) 地质调查研究院，湖北 武汉 430074
Author(s):
GUO Xian-zheng;  JIA Qun-zi;  QIAN Bing;  MI Jia-ru;  LI Jin-chao;  KONG Hui-lei;  YAO Xue-gang
1. Xi’an Center of Geological Survey, China Geological Survey, Xi’an 710054, Shaanxi, China;2. Geological Survey Institute, China University of Geosciences, Wuhan 430074, Hubei, China
关键词:
榴辉岩; 高压变质带; 地球化学; 温压计; P-T轨迹; 变质年龄; 动力学背景; 东昆仑
Keywords:
eclogite;  high pressure metamorphic belt;  geochemistry;  thermobarometer;  P-T path;  metamorphic age;  geodynamic setting;  East Kunlun
分类号:
P588.3;P595
DOI:
-
文献标志码:
A
摘要:
大陆造山带的高压—超高压变质带是古板块汇聚边界及古大洋俯冲和大陆碰撞造山的重要标志，榴辉岩作为高压变质作用形成的岩石，历来被广为关注。根据近几年东昆仑新发现的加当、苏海图、温泉、浪木日上游、宗加、五龙沟西（大格勒）等榴辉岩及榴闪岩，厘定出一条超过500 km的高压变质带，它是青藏高原北部一条重要的古板块接合带。在野外调查基础上，综合大量前人资料，从岩相学、矿物学及岩石地球化学等方面对东昆仑榴辉岩进行了系统的分析和研究。结果表明：东昆仑高压变质带榴辉岩可分为两种类型，即榴辉岩和退变质榴辉岩；石榴石矿物化学成分均表明榴辉岩为C型；榴辉岩主要为拉斑玄武岩系列，球粒陨石标准化稀土元素配分模式均为轻稀土元素富集型，主要介于富集型洋中脊玄武岩（E-MORB）与正常型洋中脊玄武岩（N-MORB）之间，原始地幔标准化微量元素蛛网图基本一致，显示出洋中脊玄武岩（MORB）特征；榴辉岩、榴闪岩温压条件近于一致，形成压力介于1.2~2.0 GPa或更高，温度不小于575 ℃，具有一个顺时针“发卡”型P-T轨迹，其变质峰期温压达到榴辉岩相；峰期变质年龄出现3个明显峰值，分别为451、432、412 Ma，432 Ma主峰期变质年龄约束了东昆仑早古生代洋盆关闭时间。
Abstract:
High-ultrahigh pressure metamorphic belt of the continental orogenic belt is the convergent boundary of the paleoplate, and is an important indicator of the palaeo-ocean subduction and the continental collision. Combined with the eclogite and garnet-amphibolite discovered in recent years, such as Jiadang, Suhaitu, Wenquan, Langmurishangyou, Zongjia, West Wulonggou (Dagele), a high pressure metamorphic belt more than 500 km is found, which is an important paleoplate suture zone in the northern Qinghai-Tibet Plateau. Based on field investigation and comprehensive previous data, the petrography, mineralogy and lithogeochemistry of eclogites in East Kunlun were studied. The results show that the eclogite in East Kunlun high pressure metamorphic belt can be divided into eclogite and retrograded eclogite, respectively; the mineral chemical component of garnet indicates that the eclogites are all C-type; the eclogites mainly belong to the tholeiite series; chondrite-normalied REE patterns show that LREE is strongly enriched between E-MORB and N-MORB; primitive mantle-normalized trace element spider diagrams are basically consistent, showing the characteristics of MORB; the temperature and pressure conditions of eclogite and garnet-amphibolite are nearly consistent, the formation pressure is 1.2-2.0 Gpa or higher, and the temperature is not less than 575 ℃; the P-T path is a clockwise “card” type; the temperature and pressure of the peak metamorphic stage are eclogite facies; according to the histogram of peak metamorphic ages of eclogites, there are three peak metamorphic ages, including 451 Ma, 432 Ma and 412 Ma; the main peak metamorphic age of 432 Ma restrains the time of Early Paleozoic ocean basin closure in East Kunlun.

参考文献/References:

-

相似文献/References:

[1]陈鑫,郑有业,许荣科,等.柴北缘超高压变质带折返过程对金红石成矿的制约：来自鱼卡和铁石观西地区石榴石成分环带的证据[J].地球科学与环境学报,2016,38(02):143.
　CHEN Xin,ZHENG You-ye,XU Rong-ke,et al.Exhumation Processes of UHP Metamorphic Belt in the Northern Qaidam and Their Constraints to Rutile Mineralization: Evidences from Compositional Zoning of Garnets in Yuqia and West Tieshiguan Areas[J].Journal of Earth Sciences and Environment,2016,38(06):143.
[2]姜为佳,刘贻灿.超高压变质带中的变质不均一性[J].地球科学与环境学报,2016,38(02):160.
　JIANG Wei-jia,LIU Yi-can.Metamorphic Heterogeneity Within a Single Ultrahigh-pressure Belt[J].Journal of Earth Sciences and Environment,2016,38(06):160.
[3]侯晨阳,杨天水,石玉若.大别超高压变质带榴辉岩中金红石SHRIMP原位U-Pb定年及其年代学意义[J].地球科学与环境学报,2016,38(03):334.
　HOU Chen-yang,YANG Tian-shui,SHI Yu-ruo.In-situ SHRIMP U-Pb Dating of Rutiles in Eclogite from Dabie UHP Metamorphic Belt and Its Geochronological Significance[J].Journal of Earth Sciences and Environment,2016,38(06):334.
[4]古晓锋,刘贻灿,刘佳.大别山镁铁质下地壳的Pb同位素成分:来自榴辉岩的制约[J].地球科学与环境学报,2017,39(01):34.
　GU Xiao-feng,LIU Yi-can,LIU Jia.Pb Isotopic Compositions of Mafic Lower Continental Crust in Dabie Orogen, China: Constraint from the Eclogites[J].Journal of Earth Sciences and Environment,2017,39(06):34.
[5]王新宇,李盛富,鄢全树.柴北缘沙柳河榴辉岩 岩石化学及变质条件研究[J].地球科学与环境学报,2005,27(01):14.
　ANG Xin-Yu,LI Sheng-fu,YAN Quan-shu.Research into petrochemistry and metamorphic condition of eclogites on Shaliuhe , the north margin of the Qaidam Basin[J].Journal of Earth Sciences and Environment,2005,27(06):14.
[6]王晓赛,杜瑾雪,王根厚.青藏高原羌塘中部榴辉岩岩石学研究进展[J].地球科学与环境学报,2017,39(05):620.
　WANG Xiao-sai,DU Jin-xue,WANG Gen-hou.Review on Petrology of Eclogites in Central Qiangtang of Qinghai-Tibet Plateau[J].Journal of Earth Sciences and Environment,2017,39(06):620.

备注/Memo

备注/Memo:
收稿日期:2017-08-29
基金项目:中国地质调查局地质调查项目(DD20160013)
作者简介:国显正(1990-),男,新疆喀什人,中国地质大学(武汉)工学博士研究生,E-mail:cuggxz@126.com。
通讯作者:贾群子(1962-),男,河南新安人,研究员,E-mail:xajqunzi@126.com。
更新日期/Last Update: 2017-12-15