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| Titel |
The role of lithology in controlling the rate of landscape response to perturbations |
| VerfasserIn |
Emma Graf, Mikael Attal, Simon Mudd, Brian Yanites |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250143188
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| Publikation (Nr.) |
 EGU/EGU2017-6890.pdf |
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| Zusammenfassung |
| Rivers form the primary link between external climatic or tectonic forcings and the
rest of the landscape as any perturbation is communicated to the entire landscape
through upstream propagation of transient signals along the fluvial network. The
transmission rate of these signals determines the response time of the landscape to a given
climatic or tectonic forcing. Understanding the controls on the propagation rate of
transient signals is therefore key to predicting the sensitivity of landscapes to future
tectonic or climatic change.While lithological characteristics, drainage area and
amplitude of the forcing have all been identified as controls on transient landscape
behaviour, the relative influence of each factor remains unclear. The influence of
lithology is particularly poorly quantified, as isolating relevant rock characteristics and
formulating them as quantifiable parameters is challenging. The Sorbas basin (SE Spain)
represents an ideal site for studying the extent to which the propagation rate of
transient signals is affected by lithology: A large-scale river capture event in the late
Pleistocene is thought to have been facilitated by a difference in lithology between the
two catchments concerned, allowing for more rapid headward erosion along the
aggressor stream. This study aims to quantify the extent to which lithology affects
transient landscape behaviour through a combination of topographic analysis of the
Sorbas basin and numerical modelling experiments using the recently developed
LithoCHILD model. Detailed topographic and stream profile analysis will be employed to
quantify the expression of the Pleistocene capture event in both catchments, and to
calibrate numerical modelling experiments simulating the evolution of the Sorbas basin
throughout the Quaternary. The study will test whether the Sorbas capture event
was facilitated by the difference in lithology between the two catchments alone,
thereby providing better constraints on the extent of lithological control on the
propagation rate of transient signals and the evolution of the drainage network. |
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