Research: Erosion

The dynamics of plate boundaries are controlled not only by the properties and deformation of the lithosphere, but also by climate-driven erosion of the deforming material. In turn, climate may be moderated by the topographic interference with atmospheric circulation patterns, and the erosional control on weathering of the silicate crust. Thus, erosion provides a powerful, two-way link between lithospheric and atmospheric processes. This link is most effective in active, compressional orogens that source most of the clastic sediment eroded from the present-day continents. In this context, the emphasis of my work is on processes, patterns and rates of erosion. I am motivated by the following questions:

  1. What are the mechanisms of the principal geomorphic processes?
  2. How do these processes interact?
  3. What determines their timing, location, and magnitude?
  4. What is the relation between geomorphic process and form?
  5. How does the landscape evolve due to changing tectonics, climate and substrate?

In natural laboratories such as Taiwan, New Zealand, Papua New Guinea and Iran I study fluvial bedrock incision, landsliding, and turbidity flow. Using hydrometric data, cosmogenic nuclides and thermochronometry I estimate current and past erosion rates. I characterise topography using digital elevation data and satellite imagery, and develop analogue and numerical models of evolving landscapes and orogens.

Recent work includes:

  • The first real time study of fluvial bedrock wear in natural channels has allowed us to validate theoretical models of river erosion, and evaluate the relative importance of floods of different magnitudes.
  • Analysis of a uniquely detailed river gauging record has shown that decadal erosion of the Taiwan orogen is controlled by seismicity and typhoon impact.
  • We have shown how a very large earthquake resonates in landsliding, sediment transfer and hyperpycnal river discharge, and calculated that the erosional impact of such earthquakes may outweigh coseismic construction of topography.
  • Bathymetric data has revealed that submarine and subaerial channelization share physics and that submarine, erosion is dominated by saturated slope failure.
  • We have developed the estimation of paleo-erosion rates using cosmogenic nuclides in dated sediments, and used this approach to study the erosional response to Quaternary climate change in Europe

Older Publications by Dr Niels Hovius


Publications: 2006-Present

Last updated on 22-Jun-10 10:22