Topography of inland deltas: Observations, modeling, and experiments

H. J. Seybold, P. Molnar, D. Akca, M. Doumi, M. Cavalcanti Tavares, T. Shinbrot, J. S. Andrade Jr., W. Kinzelbach, H. J. Herrmann
  • Geophysical Research Letters, April 2010, Wiley
  • DOI: 10.1029/2009gl041605

A REDUCED COMPLEXITY MODEL APPLIED TO SIMULATE INLAND DELTA FORMATION. Topography of inland deltas.

What is it about?

In this paper we have applied a reduced complexity model which was originally developed for coastal deltas to an inland delta, using the Okavango as reference. Elevation and slope based metrics have been used to describe the delta shape and change. Furthermore we have set up a small‐scale laboratory experiment to verify the modeling results and elucidate the time evolution of the delta system.

Why is it important?

The simple topographic measure presented, highlights the difference between inland and coastal deltas insofar as topographic slope in the latter case increases dramatically at the land‐ocean interface.

Perspectives

Dr Devrim AKCA (Author)
Isik University

A reduced complexity model is applied to simulate inland delta formation, and results are compared with the Okavango Delta, Botswana and with a laboratory experiment. We show that water loss in inland deltas produces fundamentally different dynamics of water and sediment transport than coastal deltas, especially deposition associated with expansion‐contraction dynamics at the channel head. These dynamics lead to a systematic decrease in the mean topographic slope of the inland delta with distance from the apex following a power law with exponent Alpha = −0.69 ± 0.02 where the data for both simulation and experiment can be collapsed onto a single curve. In coastal deltas, on the contrary, the slope increases toward the end of the deposition zone.

The following have contributed to this page: Dr Devrim AKCA