The Utah Geologic Survey has released a "Landslide Susceptibility Map of Utah". They apparently relied quite heavily on GIS based thresholding of existing slope angles but only after they had statistically analyzed failure angles for particular geologic units. So it sounds like they throw the known landslides, the geologic map of Utah and a DEM into the GIS a blend it all up. Perhaps a slight oversimplification!
The people living on the eastern bank of the Traunsee (map on following page) in Austria are able to observe geology in motion these days. About one million tons of soil and rock are moving in a slow landslide toward the lake, throwing over trees (picture at left) and threatening to take parts of a village with them. Moreâ€¦