Sounding out the River: Seismic monitoring of bedload transport inmountain rivers

发展和利用地震监测系统，监测山区河流河床的调动和搬运，以了解对洪水危险和河流侵蚀率的影响。项目背景：流经山区集水区的河流携带着砾石、鹅卵石和巨石组成的河床，在低流量条件下会暴露出来（图1B）。这些沉积物的侵蚀和再沉积在洪水的可能性和分布中起着重要作用，并可能影响桥梁和水坝等关键基础设施以及农业。测量调动沉积物层载所需的阈值流动条件在后勤上具有挑战性，因此研究相对不足。爱丁堡的研究已经确定了苏格兰和尼泊尔的河流，在这些河流中，测量河床搬运的临界流量条件将对了解洪水的影响作出重大贡献。最近发展起来的环境地震学领域为实现这一目标提供了基础：地震传感器可以在安全距离内记录由水和物质通量引起的信号，物理模型可以反演水力条件和层载通量的数据。在本博士课程中，您将使用低成本的地震传感器，由最先进的基准地震台站支持，结合流计数据和沉积物粒度测量，监测山地河流中河床的动员，并考虑其在洪水模型中的应用。研究问题：1；我们应该如何最好地设计一个低成本的地震监测系统来量化床质的动员和运输？冬季风暴期间，Feshie上的床质动员和搬运的时空模式是什么？它们与流量模式有何关系？如何根据你的实地调查结果来改进河床动员和搬运的时空格局的理论模型？在苏格兰的费希河（River Feshie）上吸取的经验教训如何适用于尼泊尔的活跃山区？

Develop and utilise a seismic monitoring system to monitor the mobilisation and transport of bedload in mountain rivers to understand impacts on flood hazard and fluvial erosion rates. Project Background: Rivers that drain mountain catchments carry a bedload comprised of gravel, cobbles and boulders, which are exposed during low flow conditions (Fig. 1B). The erosion and re-deposition of this sediment plays an important role in the likelihood and distribution of flooding and can impact critical infrastructure such as bridges and dams, and agriculture. Measurement of the threshold flow conditions required to mobilise sediment bedload is logistically challenging, and hence relatively understudied. Research in Edinburgh has identified rivers across Scotland, and in Nepal where measurement of the critical flow conditions for bedload transport would contribute significantly to understanding flood impact. The recently developed field of environmental seismology has delivered the foundations for tackling this goal: seismic sensors can record signals due to water and material flux at safe distance and physical models allow to invert the data for hydraulic conditions and bedload flux. In this PhD you will use low cost seismic sensors, backed up by state-of-the-art benchmark seismic stations, in conjunction with stream gauge data and sediment grainsize measurements, to monitor the mobilisation of bedload in mountain rivers and consider its application in flood models. Research Questions: 1. How should we best design a low-cost seismic monitoring system to quantify the mobilisation and transport of bedload?2. What are the spatial-temporal patterns of bedload mobilisation and transport on the Feshie during winter storms and how do they relate to patterns of discharge?3. How can theoretical models of the spatial-temporal patterns of bedload mobilisation and transport be improved based on the results of your fieldwork?4. How well do the lessons learned on the River Feshie in Scotland scale to an active mountain setting in Nepal?