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

横贯南极中部山脉变质岩的岩石成因和地壳结构：综合岩石学、构造和年代学研究

• 批准号: 8816807
• 负责人: John Goodge
• 金额: $ 26.47万
• 依托单位: Southern Methodist University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-06-01 至 1993-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8816807&HistoricalAwards=false
• 关键词: Petrogenesis; Crustal; Structure; Metamorphic; Rocks

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.

本文对南极横贯山脉中部前寒武纪基底岩的区域变质与变形进行了研究。这些岩石意义重大，因为它们构成了横贯南极山脉中唯一暴露的高等级基底地形，而横贯南极山脉代表了古南极东部克拉通的一部分。因此，它们的岩石成因和构造演化对于更好地理解古南极克拉通是如何演化的以及冈瓦纳超大陆是如何形成的非常重要。这些岩石靠近西南极洲克拉通边缘的位置为研究太古宙和元古代盾构构造元素之间的关系提供了一个独特的机会，更年轻的地壳元素沿着南极板块边界汇聚形成。这项变形前寒武纪变质地形的综合研究将包括：1)详细的野外地质填图和采样；2)结构、微观结构、运动学和织物分析；3)变质岩石学和定量地温测量，包括主元素交换和氧同位素技术；4)同位素地球年代学。拟议项目的期限为三年，包括头两年的实地季节。