The School of Geography, Earth and Environmental Sciences organises a regular series of research seminars throughout the academic year to which everyone is welcome to attend. Speakers - both external and internal to the University - will talk on topics related to all aspects of Earth Sciences.
Today's speaker is Dr Daniel Hobley from Cardiff University.
The rates, magnitudes, and timing of erosion in mountain rivers are important in a variety of geological disciplines, including geomorphology, sedimentology, and tectonics. Eroding landscapes also record evidence of past changes in Earth’s climatic and tectonic regimes, that may be difficult to access by other means. Traditionally, this kind of erosion has been described by simple models describing the work done by the river. However, an increasing body of evidence from theory, experiment, and targeted case studies indicates that the story cannot be this simple, and that the amount of sediment in the river is a key additional factor in controlling erosion rates.
In this talk, Daniel will illustrate the ways these sediment-flux-dependent responses differ from the simpler descriptions, then use these responses to argue that this style of erosion is in fact ubiquitous in mountain rivers. With this in mind, Daniel will then illustrate the kinds of trouble we can get ourselves into if we blithely assume that we can ignore these effects and deploy the simpler models. To conclude, Daniel will discuss how the ubiquity of sediment-flux-dependent erosion impacts our ability to 'read' both landscapes and the sedimentary rock record.