Constraining the Nature and Formation Age of the Shyok Suture Zone in Ladakh, NE India

限制印度东北部拉达克什约克缝合带的性质和形成时代

• 批准号: 1902179
• 负责人: Oliver Jagoutz
• 金额: $ 40.99万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-15 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1902179&HistoricalAwards=false
• 关键词: Constraining; Nature; Formation; Age; Shyok

The spectacular height and length of the Himalayan Mountain Belt has inspired generations of people across the world. The mountain chain was formed during the collision of the Indian and Eurasian continents approximately 40-50 million years ago. Before this collision occurred, an ocean called the Neotethys separated the two continents and the timing of its disappearance remains an open question. This project will better constrain the timing of the collision between the two continents by age dating and paleomagnetic measurements in the Kohistan-Ladakh region of northern India. A better constraint on the timing of the collision and disappearance of the Neotethys ocean is essential not only for our understanding of the Himalayas, but also for addressing other big questions such as the how tectonic plates reorganize during major collisional events and the influence of tectonic forces on global climate.The principal goals of this project are to better constrain the nature and age of the Shyok suture zone, and to test alternative models for the Kohistan-Ladakh-Eurasia collision. If the Shyok suture is younger than the Indus suture, then the Shyok-Tsangpo suture zone, not the Indus-Tsangpo suture zone, records the final collision of India and Asia, and two subduction systems were present in the Neotethys ocean until approximately 50 Ma. We will conduct a detailed study combining field geologic mapping, petrology/geochemistry, U-Pb zircon geochronology, and paleomagnetic measurements. This work will constrain the currently unknown age and provenance of multiple sedimentary sequences in the suture zone as well as provide new information on the geochemical characteristics and ages of plutonic rocks within the suture and in neighboring terranes. Additionally, the proposed paleomagnetic work will determine the unknown paleolatitudes of both the Kohistan-Ladakh arc and Eurasian margins during the crucial time of the India-Eurasia collision and thus allow us to evaluate the different collision scenarios. The work related to this project constitutes a comprehensive and multifaceted documentation of a pivotal yet unconstrained suture zone in the Himalaya and offers the opportunity to capitalize on the recently increased access to crucial exposures in Ladakh, India.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

喜马拉雅山带的壮观高度和长度激发了世界各地的几代人。 这座山脉是在大约400至5000万年前在印度和欧亚大陆碰撞期间形成的。 在发生这次碰撞之前，一个称为Neotethys的海洋将两大洲分开，消失的时机仍然是一个悬而未决的问题。该项目将更好地限制印度北部Kohistan-Ladakh地区的年龄约会和古磁测量的两大洲碰撞的时机。 更好地限制了Neotthys海洋碰撞和消失的时间的限制，这不仅对我们对喜马拉雅山脉的理解至关重要，还可以解决其他大问题，例如在重大碰撞事件中如何重新组织构造构成构造力量以及构造力量对全球气候的影响。 Kohistan-Ladakh-Eurasia碰撞。如果Shyok缝合线比印度缝线年轻，那么Shyok-Tsangpo缝合区（而不是Indus-Tsangpo缝合区）记录了印度和亚洲的最终碰撞，并且在Neotethys海洋中存在两个俯冲系统，直到大约50 mA。 我们将进行一项详细的研究，结合了田间地质图，岩石学/地球化学，U-PB锆石地质学和古磁测量。这项工作将限制当前未知的缝合区沉积序列的年龄和出处，并提供有关缝合线和邻近地形内岩化岩石的地球化学特征和年龄的新信息。此外，提出的古磁性工作将确定在印度 - 欧洲裔碰撞的关键时期，Kohistan-Ladakh-Ladakh弧和欧亚边缘的未知古素会，因此使我们能够评估不同的碰撞场景。与该项目相关的工作构成了喜马拉雅山中关键但不受限制的缝合区的全面且多方面的文档，并提供了机会，可以利用印度拉达克的最近增加至关重要的暴露范围。该奖项反映了NSF的法定任务，并通过评估了基金会的范围，并通过评估了基金会的范围。