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

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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?