Petrogenesis and Crustal Structure of Metamorphic Rocks in the Central Transantarctic Mountains: An Integrated Petrologic, Structural and Geochronologic Study

本研究将集中于南极横贯北极山脉中部前寒武纪基岩的区域变质和变形。这些岩石意义重大，因为它们包含了横跨北极山脉中唯一暴露的高级地下室地形，这些山脉代表了古老的东南极克拉通的一部分。因此，它们的岩石成因和构造演化对于更好地了解古南极克拉通是如何演化和超大陆冈瓦那是如何形成的具有重要意义。这些岩石位于西南极克拉通边缘附近，为研究太古宙和元古界的构造元素与沿汇聚的南极板块边界形成的年轻地壳元素之间的关系提供了独特的机会。这项变形前寒武纪变质地体的综合研究将包括：1)详细的野外地质填图和取样；2)构造、微构造、运动学和组构分析；3)变质岩石学和定量地温压测量，包括主要元素交换和氧同位素技术；4)同位素测年。拟议项目的期限为三年，包括头两年的田间季节。

This study will focus on the regional metamorphism and deformation of Precambrian basement rocks in the central Transantarctic Mountains of Antarctica. These rocks are significant because they comprise some of the only high-grade basement terrains exposed in the Transantarctic Mountains which represent a part of the ancient East Antarctic craton. As such, their petrogenesis and tectonic evolution are important for a better understanding of how the paleo-Antarctic craton evolved and how the supercontinent Gondwana formed. The position of these rocks near the edge of cratonal West Antarctica provides a unique opportunity to study the relation between the tectonic elements of the Archaen and Proterozoic shield, and younger crustal elements formed along a convergent Antarctic plate boundary. This integrated study of deformed Precambrian metamorphic terrains will involve: 1) detailed field geologic mapping and sampling; 2) structural, microstructural, kinematic and fabric analysis; 3) metamorphic petrology and quantitative geothermobarometry involving both major element exchange and oxygen isotope techniques; and 4) isotopic geochronometry. The duration of the proposed project is three years, including field seasons during the first two years.