Abstract
A one-dimensional model that is able to store the stratigraphy emplaced by a
prograding delta is validated against experimental results. The laboratory
experiment describes the migration of a Gilbert delta on a sloping basement
into standing water, i.e., a condition in which the stratigraphy emplaced by
the delta front is entirely stored in the deposit. The migration of the
delta front and the deposition on the delta top are modeled with total and
grain-size-based mass conservation models. The vertical sorting on the delta
front is modeled with a lee-face-sorting model as a function of the grain
size distribution of the sediment deposited at the brinkpoint, i.e., at the
downstream end of the delta top. Notwithstanding the errors associated with
the grain-size-specific bedload transport formulation, the comparison
between numerical and experimental results shows that the model is able to
reasonably describe the progradation of the delta front, the frictional
resistances on the delta top, and the overall grain size distribution of the
delta top and delta front deposits. Further validation of the model in
the case of variable base level is currently in progress to allow for future
studies, at field and laboratory scale, on how the delta stratigraphy is
affected by different changes of relative base level.
Citation
ID:
240103
Ref Key:
viparelli2014earthcomparison