Collaborative Research: Using a weather model and geologic data to test tectonic mechanisms in an intercontinental setting: The Altai Mountains of Central Asia

合作研究：利用天气模型和地质数据测试洲际环境中的构造机制：中亚阿尔泰山脉

• 批准号: 2316735
• 负责人: Rene Paul Acosta
• 金额: $ 3.5万
• 依托单位: George Mason University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2316735&HistoricalAwards=false
• 关键词: Collaborative; Research; Using; weather; model

The height and shape of mountain ranges exert a profound influence on the world around us. Mountains host a variety of ecological habitats, provide much of the water and nutrients necessary for life, the critical minerals needed for society, and influence climate and weather patterns. The size and shape of mountains reflect the underlying solid Earth processes responsible for how the crust deforms, for earthquakes, and for related natural hazards. Despite their importance, it remains exceptionally difficult to recover the history of mountains including how changes in their height and shape interact with the atmosphere to drive climate and weather. This project seeks to apply new advances in the atmospheric and geosciences to a natural experiment in central Asia where the height and shape of the Altai Mountains over the past 50 million years are thought to have precipitated a major change in atmospheric circulation and in climate. The Altai are one of the major ranges in Asia that substantially modify regional climate and ecosystems and spawn some of the largest intracontinental earthquakes ever recorded. This research will use a novel weather model to predict changes in atmospheric circulation and climate in response to the size, height, and growth history of the Altai. These model predictions will be measured against field and laboratory data gleaned from the sediments shed from the Altai. Using rock magnetic data preserved in the sediments, and the steepness of river channels carved into the mountains, the principal investigators will be able to construct an age model consistent with the onset and growth history of the Altai range. This interdisciplinary approach will be pursued by a multi-university, diverse team in the U.S. that includes early-career professors, graduate students and undergraduates in collaboration with Mongolian colleagues at the Institute for Astronomy and Geophysics. The project will train three PhD students, three early-career scientists, and one undergraduate in inter-disciplinary geosciences and build international exchange opportunities. The results of this research will improve understanding of the coupling among solid Earth and atmospheric processes and contribute to addressing societal challenges, such as building resistance to climate change and to earthquake-related natural hazards. Mountain topography reflects complex couplings among tectonic, dynamic, and surficial processes and influences climatic evolution, marine and terrestrial biogeochemistry, and even the development of biodiversity. Unfortunately, the climatic proxies which are so often used to reconstruct past topography are themselves dependent upon a variety of other factors. Consequently, constraining the tectonic and/or dynamic processes that are responsible for the height of mountains remains exceptionally difficult. This project will leverage novel advances in the atmospheric sciences to understand topographic growth beyond the simple upslope model of orographic rainout. The project focuses on the Altai Mountains of northern Central Asia, a poorly understood Cenozoic rejuvenation of the Central Asia Orogenic Belt that rises more than 4 kilometers, casts a substantial rain shadow, and is associated with some of the largest intracontinental earthquakes on record. Altai uplift has been variously attributed to far-field stress propagation from the collision of India and Eurasia or to dynamic support from a mantle plume, a subducting slab, or lithospheric delamination. Each of these uplift mechanisms predict a unique spatial and temporal pattern of rock uplift and of regional climate change, based upon how and when these uplift mechanisms modified the height, shape, and orientation of the Altai. Existing data are contradictory; sedimentary, geomorphic, and thermochronologic data indicate that tectonic uplift began in the Paleogene, whereas paleoclimate data from both windward and leeward basins suggest no clear climatic change until the late Miocene, when there appears to be substantial aridification in western Mongolia. The project focuses on collecting new spatially-resolved rock uplift data using inversions of fluvial topography and new stable and clumped isotope records of paleoclimate from leeside basins. The age model for both rock uplift and of climatic change across western Mongolia will be constrained by magneto- and cyclostratigraphic-based age models of adjacent, syn-deformational basin sediments. The Weather Research and Forecasting model will be used to predict the climate impact of distinct Altai topographic histories. Combined, these data sets permit tests of the theories that seek to explain Cenozoic Altai uplift.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.

山区的身高和形状对我们周围的世界产生了深远的影响。山脉拥有各种生态栖息地，提供了生命所需的许多水和营养，社会所需的关键矿物质以及影响气候和天气模式。山的大小和形状反映了构成地壳，地震和相关自然危害的基础固体过程。尽管它们的重要性，但仍难以恢复山脉历史，包括其身高和形状的变化如何与大气相互作用以驱动气候和天气。该项目旨在将大气和地球科学的新进展应用于中亚的自然实验，在过去的5000万年中，阿尔泰山脉的身高和形状被认为促成了大气循环和气候下的重大变化。阿尔泰（Altai）是亚洲的主要范围之一，该范围实质上改变了区域气候和生态系统，并产生了有史以来最大的肠内地震。这项研究将使用一种新型的天气模型来预测大气循环和气候的变化，以响应Altai的大小，身高和生长历史。这些模型预测将根据从阿尔泰（Altai）脱落的沉积物收集的现场和实验室数据来衡量。使用保存在沉积物中的岩石磁数据，以及雕刻到山脉的河道的陡度，主要研究人员将能够构建与Altai范围的发作和生长历史一致的年龄模型。这种跨学科的方法将由美国的多元大学，包括早期职业教授，研究生和本科生在内的多元化团队与蒙古同事在天文学和地球物理学研究所合作。该项目将培训三名博士生，三名早期职业科学家和一名本科生跨学科地球科学的本科生，并建立国际交流机会。这项研究的结果将改善对固体地球和大气过程之间的耦合的理解，并有助于应对社会挑战，例如建立对气候变化和地震相关的自然危害的抵抗力。 山地形反映了构造，动态和表面过程之间的复杂耦合，并影响了气候进化，海洋和陆地生物地球化学，甚至是生物多样性的发展。不幸的是，经常用于重建过去地形的气候代理本身取决于其他各种因素。因此，限制负责山区高度的构造和/或动态过程仍然非常困难。该项目将利用大气科学的新进展来了解超出简单的地形雨模型之外的地形增长。该项目着重于中亚北部的阿尔泰山脉，在中亚造山带中，人们对中亚亚造山带的新生代恢复活力鲜明，它升高了4公里以上，造成了实质性的雨阴影，并且与有史以来最大的洪流局内地震有关。 Altai的隆起归因于印度和欧亚大陆碰撞或地幔羽，俯冲板或岩石圈分层的动态支撑的远场应力传播。这些隆升机制中的每一个都预测了岩石隆升和区域气候变化的独特空间和时间模式，这些机制基于这些隆起机制如何以及何时改变了阿尔泰的高度，形状和方向。现有数据是矛盾的；沉积，地貌和热量编量数据表明，构造隆起始于古纪开始，而来自风向和背风盆地的古气候数据都没有明显的气候变化，直到中新世晚期，西蒙古里亚（Western Mongolia）似乎有实质性的干旱化。该项目着重于使用河边盆地的新稳定和结块的同位素记录来收集新的空间分辨岩石提升数据。整个蒙古西部的岩石隆起和气候变化的年龄模型将受到基于磁和环形学的基于邻近的，具有同步的盆地沉积物的年龄模型。天气研究和预测模型将用于预测不同Altai地形历史的气候影响。这些数据集结合在一起，允许对试图解释新生代阿尔泰提升的理论进行测试。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响评估标准，被认为值得通过评估来提供支持。