Theory for the curvature dependence of delta front progradation
Journal
Geophysical Research Letters
Journal Volume
42
Journal Issue
24
Pages
10680-10688
Date Issued
2015
Author(s)
Abstract
Abstract When Gilbert‐type deltas respond to uneven sediment supply or advance over irregular basin bathymetry, they develop curved, creased fronts prograding at speeds that vary with location along the shoreline. Relations governing the progradation rate, however, have so far been proposed only for simple special cases. In this paper, we exploit the special properties of solutions to the eikonal equation to derive a general progradation relation, applicable to delta fronts of finite angle of repose and arbitrary shoreline planform. In these circumstances, the theory explicitly relates the progradation rate to the local shoreline curvature. We illustrate the resulting morphodynamics with numerical and analytical solutions for a sinuous delta front. The proposed relation can be used to model deltaic evolution or deduce spanwise distributions of sediment supply rates from observations of foreset evolution.
SDGs
Type
journal article