A collegue here has a problem I cannot help with. She has the surface (as raster) of a landslide release area (from AFTER the slide) and wants to calculate the calculate the theoretical/approximate volume of the release surface. Is there a funtion in ArcGIS or GRASS GIS 7 that fills the slide relesease area? The problem is that we do not have the pre-release surface, so cut/fill does not work here.
Do the cell values of the raster represent release volume or is the raster simply imagery (e.g. aerial/satellite)? Do you have a polygon (vector) representing the slide region?
If the raster does represent volume, and you have a polygon for the slide region, then you should be able to run zonal statistics tool from ArcGIS Spatial Analyst and get the descriptive statistics for the area.