gis-model, erosion, simulation

Hi folks,

I would like to create a simulation model for erosion. The data I use come
from a laser relief micrometer. The aim is to describe the surface roughness
at this microscale.
Is there anybody who has experience in building such a model?
What components (rain, soil-type???) should I take up?
Does anybody know an algorithm to create an artificial soil surface (ASCII,
GIF, TIFF ...)?

Thanks in advance

Harry Sommer
                                                
Lehreinheit fuer Mathematik, Statistik und
Datenverarbeitung
Hohenbachernstrasse 2
85350 Freising
Germany
________________________________________________
e-mail: harry@castor.edv.agrar.tu-muenchen.de