Catastrophic emplacement and depositional processes during large asteroid impacts: lithofacies analysis and applied volcanology, Manicouagan (Canada)

大型小行星撞击期间的灾难性侵位和沉积过程：岩相分析和应用火山学，马尼瓜根（加拿大）

• 批准号: 2609781
• 金额: --
• 依托单位: University of Leicester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2609781
• 关键词: Catastrophic; emplacement; depositional; processes; during

When asteroids or comets collide with Earth they cause catastrophic shock, vaporisation, melting, fragmentation and ejection, significantly modifying the crust and devastating environments and biota. Such 'hypervelocity collisions' are a fundamental process of planetary evolution and arguably the greatest natural hazard. Significant advances in shock metamorphism, petrology and modelling have been made, but several geological aspects of what happens remain poorly understood. We need to better understand the processes of molten ejecta emplacement in order to account for the wider effects. A principle source of information lies in Earth's geological record, but accessible, well-preserved large impact craters filled with clastic and melted products are rare.This project will help decipher the fragmentation and emplacement processes of crater-fill material in very large impact craters on Earth, focussing on Manicouagan (Canada) and Chicxulub (Mexico). Both impacted continental crust, one on land the other at sea, and both have been drilled. The investigation will document, analyse and interpret the crater fills to shed new light on the physical processes of their formation. The student will draw upon state-of-the-art geological and physical volcanological techniques and understanding about how hot magma is fragmented, emplaced, and then deposited and agglutinated back together to form thick rock bodies that subsequently cool, and variously devitrify and crystallise. An objective is to develop a new facies scheme for large impact crater fills in order to help reconstruct the events by which they form.

当小行星或彗星与地球碰撞时，它们会引起灾难性的休克，蒸发，融化，碎片化和射血，显着改变了外壳和毁灭性的环境和生物群。这种“高速碰撞”是行星进化的基本过程，可以说是最大的自然危害。冲击变质，岩石学和建模的重大进展，但发生的事情的几个地质方面仍然很少理解。我们需要更好地理解熔融射出的进程的过程，以说明更广泛的影响。信息的主要来源在于地球的地质记录，但很少见，可访问，保存完好的大型影响坑，充满了碎屑和融化的产品。该项目将有助于解释地球上非常大的地球壁corter的火山口材料的碎片化和埋入过程，专注于Manicouagan（Canada）和PiChulub（Canada）和Chicxulub（Canada）和Chicxulub（Mexculub（Mexculub）。两者都影响了大陆地壳，一个在海上的另一个土地上，都钻了钻。该调查将记录，分析和解释火山口填充，以解散其形成的物理过程。该学生将利用最先进的地质和物理火山技术技术，并了解热岩浆的碎片碎片，扩散，然后沉积和凝聚在一起，形成厚的岩石体，随后冷却，并变化，并变化并结晶。一个目标是为大型影响火山口填充制定新的相计划，以帮助重建它们形成的事件。