Did Channel Flow Drive the Thermo-mechanical Evolution of the Eastern Himalaya? A Field-based Test in Northeast Bhutan

河道流驱动了喜马拉雅东部的热机械演化吗？

• 批准号: 1220300
• 负责人: Stacia Gordon
• 金额: $ 39.3万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1220300&HistoricalAwards=false
• 关键词: Did; Channel; Flow; Drive; Thermo

The Himalayan range and Tibetan Plateau represent the world?s tallest mountain range and largest area of elevated land, and are the type-example of a mountain belt that formed as a result of continent-continent collision. This system is still actively growing; therefore, study of these mountains provides a unique opportunity to understand how the crust evolves during this type of plate collision. Across much of the Himalayan range, rocks that have been buried to depths as much as approximately 35 km below Earth's surface and taken to temperatures hot enough to partially melt are observed at the surface today. These rocks have been studied in many parts of the Himalaya, and there is currently a vigorous debate over how these rocks were exhumed to the surface. The channel flow model predicts that these deeply buried rocks lost much of their strength after partially melting, and were then translated southward and towards the surface. In comparison, other proposed models argue that faults and shear zones were responsible for their exhumation, and are less focused on the driving force being the weakness of the rocks. In this project, we propose to test the applicability of these different models to rocks in the kingdom of Bhutan, which lies in the eastern part of the Himalayan range. We will do this by collecting rock samples during field expeditions, and determining the pressure, temperature, timing, and evolution of deformation that they experienced. In the past, Bhutan has been relatively isolated for geologic researchers so the majority of the rocks exposed in Bhutan have not been well studied.The results of this project will make a valuable contribution to the debate over how continental crust evolves during collisional mountain building. In addition, multiple graduate students will be trained in the field and laboratory, including one Bhutanese citizen and current employee of Bhutan's geologic survey. After he finishes his degree, he will return to Bhutan to take on a leadership role in the study of natural resources, natural hazards, and public policy. Undergraduate students will also be involved with laboratory analyses and will obtain training, education, and research experience. Finally, this study will support the research efforts of two early career researchers, as well as foster valuable international collaboration between UNR and scientists at Bhutan?s geological survey.

喜马拉雅山脉和青藏高原代表世界？它是中国最高的山脉和最大的高地，是大陆碰撞形成的山脉带的典型。 这个系统仍在活跃地增长;因此，对这些山脉的研究提供了一个独特的机会，以了解地壳在这种类型的板块碰撞过程中如何演变。 在喜马拉雅山脉的大部分地区，今天在地表观察到的岩石被埋在地表以下约35公里的深处，温度高到足以部分融化。 喜马拉雅山的许多地方都对这些岩石进行了研究，目前关于这些岩石是如何被挖掘到地表的争论激烈。 通道流动模型预测，这些深埋的岩石在部分熔融后失去了大部分强度，然后向南移动并朝向地表。 相比之下，其他提出的模型认为，断层和剪切带负责他们的折返，并不太注重的驱动力是岩石的弱点。 在这个项目中，我们建议测试这些不同的模型在不丹王国，位于喜马拉雅山脉东部的岩石的适用性。 我们将通过在野外考察期间收集岩石样本，并确定它们所经历的压力，温度，时间和变形的演变来做到这一点。 在过去，不丹一直是相对孤立的地质研究人员，使大多数的岩石暴露在不丹没有得到很好的研究。该项目的结果将作出宝贵的贡献，辩论大陆地壳如何演变在碰撞造山作用。 此外，多名研究生将接受实地和实验室培训，其中包括一名不丹公民和不丹地质调查局的现任雇员。 完成学位后，他将返回不丹，在自然资源，自然灾害和公共政策的研究中发挥领导作用。 本科生也将参与实验室分析，并将获得培训，教育和研究经验。 最后，这项研究将支持两个早期职业研究人员的研究工作，以及促进UNR和不丹科学家之间的宝贵的国际合作？的地质调查。