Wind over rock: Quantifying the feedbacks among wind flow, bedrock erosion, and tectonic uplift

地球上基岩侵蚀率最高的地区通常被认为是受大河和冰川作用影响的陡峭地区。然而，在世界上的许多沙漠中，风和风沙是主要的侵蚀因素，在那里，即使是相对平坦的基岩地貌也会像地球上侵蚀速度最快的河流和冰川山谷一样被侵蚀。对于风和风沙是如何侵蚀基岩的，以及是什么变量控制了在这些地区形成的主要地貌——沙丘的形态，人们所知相对较少。风蚀还可以通过减少高侵蚀区（即在滑动断层或生长褶皱的迎风面）地形造成的应力，影响地壳断层和褶皱的行为。进一步的全球气候变化可能会导致更多的荒漠化，使风蚀及其对人类的影响（例如空气质量下降）变得更加重要，需要了解和预测。这个项目将提高我们量化风蚀的能力，这是一个影响人类健康和土地可持续性的过程。该项目包括南加州和青藏高原柴达木盆地的野外地区（与中国同事合作）。我们将结合野外工作、遥感、数值模拟和地质年代学来量化风和风沙在地形上的流动、地形的侵蚀以及地壳断层和褶皱的行为之间的相互作用。该项目由地貌与土地利用动力学项目、构造学项目和美国国家科学基金会OIIA国际科学与工程部共同支持。

The highest rates of erosion of bedrock on Earth are generally thought to occurin steep areas subject to the action of large rivers and glaciers. However, there are many deserts around the world where wind and wind-blown sand are the dominant agents of erosion and where even relatively flat bedrock landforms can be eroded as quickly as the fastest eroding rivers and glacial valleys on Earth. Relatively little is known about how wind and wind-blown sand erodes bedrock andwhat variables control the morphology of yardangs, the dominant landforms createdin such areas. Wind erosion can also influence the behavior of faults and folds in the Earth's crust by reducing the stress caused by topography in areas of high erosion (i.e. on the windward side of a slipping fault or growing fold). Further global climate changes will likely lead to more desertification, making wind erosion and its impacts on humans (e.g. reduced air quality) even more important to understand and predict. This project will improve our ability to quantify wind erosion, a process influencing human health and land sustainability. The project includes field areas in southern California and the Qaidam Basin of the Tibetan Plateau (in collaboration with Chinese colleagues). We will combine field work, remote sensing, numerical modeling, and geochronology to quantify the interaction between the flow of wind andwind-blown sand over topography, the erosion of that topography, and the behaviorof faults and folds in Earth's crust. This project is jointly supported by the Geomorphology and Land-use Dynamics Program, Tectonics Program, and NSF's OIIA International Science and Engineering Section.