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The erosion on Mars is poorly understood, especially the fluvial erosion, which modified obviously the surface of the Red Planet. There are several erosion models for the terrestrial environment. These models are without climbing completeness: USLE, USPED and SIMWE [1]. All of the listed models use physical variables, but most physical variables are available on SIMWE (SImulated Water Erosion) model. These are: elevation model, first order derivative of the slope (E-W and N-S direction), runoff infiltration rate, Manning’s value, rain event duration (min) and unique value (mm/hr), detachment coefficient, transport coefficient, critical shear stress. These variables are divided in two different GRASS GIS scripts: r.sim.water [2] and r.sim.sediment [3]. A former simulation used the SIMWE model on a Martian valley system, which is near to Tinto Vallis, in this case it is called Tinto B (2°55’ S, 111°53’ E). The first type of SIMWE model used the erodibility parameter (K-factor, based on the TES dataset), 15 mm/hr rain event, which held 5 minutes and used the default given parameter for the detachment (Dc) and the transport (Tc) coefficiente and critical shear stress. With these settings the SIMWE model gives a detailed map, which shows the small drainages, which are non- or barely visible on the CTX images. The second version of the model modified parameters, which come from the THEMIS thermal-inertia dataset. The K-factor sand related variable was modified with the normalised value of the thermal-inertia (local maximum of thermal-interia = 1). The variables for the detachment and transport coefficients were calculated also from the thermal-inertia values, and are equivalent with the sediment diameter sizes [4]. These converted sizes re related to the Shields parameter and critical bed shear stress [5]. From these variables the the detachment and the transport coefficient can be determined with the following equations: Tc=A/( |
