Fluvial bedrock abrasion by bedload: process and form

Abstract

Bedrock channels are a key component of the landscape. Fluvial bedrock incision sets the local base level, the boundary condition for hill slope processes, transmits tectonic and climatic signals throughout the landscape and transports sediments to sedimentary basins. Bedrock river networks are also responsible for the texture and relief of an unglaciated landscape, and in flexural landscapes bedrock channels significantly effect rates and patterns of erosional unloading and consequently long-term sediment fluxes to basins. This thesis investigates the mechanism and morphological expression of one of the key mechanisms of erosion in bedrock river incision: abrasion by bedload. Both long term landscape evolution and physical process based models of bedrock incision would benefit from a better understanding of the controls and behaviour of the abrasion process in natural substrates and settings.