RT Journal Article T1 Mathematical Analysis of a Model of River Channel Formation A1 Díaz Díaz, Jesús Ildefonso A1 Fowler, A.C. A1 Muñoz, Ana Isabel A1 Schiavi, Emanuele AB The study of overland flow of water over an erodible sediment leads to a coupled model describing the evolution of the topographic elevation and the depth of the overland water film. The spatially uniform solution of this model is unstable, and this instability corresponds to the formation of rills, which in reality then grow and coalesce to form large-scale river channels. In this paper we consider the deduction and mathematical analysis of a deterministic model describing river channel formation and the evolution of its depth. The model involves a degenerate nonlinear parabolic equation (satisfied on the interior of the support of the solution) with a super-linear source term and a prescribed constant mass. We propose here a global formulation of the problem (formulated in the whole space, beyond the support of the solution) which allows us to show the existence of a solution and leads to a suitable numerical scheme for its approximation. A particular novelty of the model is that the evolving channel self-determines its own width, without the need to pose any extra conditions at the channel margin. PB Birkhäuser SN 0033-4553 YR 2008 FD 2008-10-29 LK https://hdl.handle.net/20.500.14352/49915 UL https://hdl.handle.net/20.500.14352/49915 LA eng NO DGISGPI (Spain) NO Mathematics Applications Consortium for Science and Industry NO DGUIC DS Docta Complutense RD 6 abr 2025