"Magmatism, metallogeny and tectonics of the Paleoproterozoic core of Canada"

“加拿大古元古代核心的岩浆作用、成矿和构造”

• 批准号: 155085-2012
• 负责人: Ansdell, Kevin
• 金额: $ 1.97万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=522553
• 关键词: Magmatism; metallogeny; tectonics; Paleoproterozoic; core

The Earth's continental crust consists of fragments of ancient igneous and sedimentary rocks that record a complex geological history of crustal growth and reworking over the last 4 billion years. The Precambrian Shield makes up a significant portion of the crust in Canada, and many of the Archean (>2.5 billion years old) components were joined together about 1.8 billion years ago during a cataclysmic collision, called the Trans-Hudson orogeny, that is preserved in a linear belt that extends from Saskatchewan to Baffin Island. The collision, which was related to the motion of lithospheric plates, formed a mountain range that was probably of the same scale as the present-day Himalayas. In the lead up to the collision, there were complex interactions between different crustal elements which generated magmas, sediments, and structures. The aim of part of this research, which involves mapping and sampling in the field by a number of graduate and undergraduate students, and the application of modern analytical techniques for the analysis of trace elements and isotopes is to unravel the interaction between different crustal blocks prior to the major collision 1.8 billion years ago. It will be necessary to define the composition of different parts of the crust and mantle in order to understand how they interacted.

地球的大陆地壳由古老的火成岩和沉积岩碎片组成，记录了过去 40 亿年来地壳生长和改造的复杂地质历史。前寒武纪地盾构成了加拿大地壳的重要组成部分，许多太古代（>25亿年）的组成部分在大约18亿年前的一次灾难性碰撞中连接在一起，称为跨哈德逊造山运动，该运动保存在从萨斯喀彻温省延伸到巴芬岛的线性带中。这次碰撞与岩石圈板块的运动有关，形成了一座山脉，其规模可能与今天的喜马拉雅山相当。在碰撞之前，不同地壳元素之间存在复杂的相互作用，产生了岩浆、沉积物和结构。这项研究的部分内容包括由一些研究生和本科生在现场进行绘图和采样，以及应用现代分析技术进行微量元素和同位素分析，其目的是揭示 18 亿年前大碰撞之前不同地壳块之间的相互作用。有必要定义地壳和地幔不同部分的组成，以便了解它们如何相互作用。