Metamorphic evolution and tectonic significance of high-P metamorphic rocks in the Palaeoproterozoic: the Nagssugtoqidian Orogen, South East Greenland.

古元古代高磷变质岩的变质演化及其构造意义：格陵兰岛东南部纳格苏格托奇甸造山带.

基本信息

批准号：
239661242
负责人：
Professorin Dr. Annika Dziggel
金额：
--
依托单位：
Institut für Geologie, Mineralogie und Geophysik
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2017-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/239661242?language=en
关键词：
Metamorphic evolution tectonic significance metamorphic

项目摘要

This project aims to investigate the pressure-temperature-time-deformation evolution of high-pressure metamorphic rocks in the Palaeoproterozoic Nagssugtoqidian Orogen in South-East Greenland. The Nagssugtoqidian Orogen is unique in that it is one of a few Palaeoproterozoic collisional orogens, in which high-pressure metamorphic rocks have been preserved. Relict eclogites and/or high-P granulites occur within mafic dykes in the orthogneiss-dominated core of the orogen. Mineral assemblages of garnet and clinopyroxene as well as clinopyroxene-plagioclase symplectites indicate PT-conditions outside the plagioclase stability field. Preliminary work to this project indicates that the rocks underwent retrogression at medium-to high-pressure granulite facies grades, but it is currently unknown from which crustal depth these rocks were exhumed. In collaboration with the Geological Survey of Denmark and Greenland (GEUS), the research will combine pressure-temperature-time paths obtained from pseudosection modelling and U-Pb dating of minerals such as zircon, rutile, and titanite with detailed kinematic investigations of shear zones to the north and south of the high-P domain. The data will not only give new insights into the tectonic evolution and exhumation history of high-pressure rocks in the Nagssugtoqidian Orogen, and will also provide constraints on the geodynamic processes during the formation the supercontinent Nuna in the mid Palaeoproterozoic.

该项目旨在研究古田元中古代古代古代纳格斯苏格托奇奇造基地中高压变质岩石的压力温度变形的演变。 nagssugtoqidian造成造成是独一无二的，因为它是少数古代古代碰撞的牙齿，其中保留了高压变质岩石。遗物的eclogites和/或高-P颗粒物发生在植物骨的植物中的镁铁质堤防中。石榴石和斜石的矿物组合以及斜磷酸岩岩酶Symphectites表示斜长石稳定性领域以外的PT条件。该项目的初步工作表明，这些岩石在中型高压颗粒相的等级上进行了倒流，但目前尚不清楚这些岩石被挖掘出来。与丹麦和格陵兰（GEU）的地质调查局合作，该研究将结合从伪选择建模和矿物质的U-PB年代获得的压力 - 温度时间路径，例如氧化锆，金红石和钛铁矿等详细的运动区域的剪切区域，该运动区域的剪切区域北部和南部的高点南部和南部。这些数据不仅将提供有关Nagssugtoqidian骨基因中高压岩石的构造演化和挖掘历史的新见解，而且还将在形成期间对中元中元中的超大通NUNA的地球动力学过程提供约束。