Abstract:
The Russian River Landslide Potential Model was derived from two grids, a geology grid and a slope grid. The geology grid was originally in a shapefile format and converted to a grid using a 10m (meter) cell size. The slope grid was generated from a 10-meter DEM (Digital Elevation Model) and also has a 10m cell size.
The GIS analysis that was performed in this model was taking the geology & slope grids and overlaying the two datasets. A predeteremined set of values were then applied in each instance where a geologic unit covered a particular slope percentage and a new grid was created. The predetermined set of values are contained in a matrix, which is created by the geologist and based upon the data and their knowledge of the watershed. See report for matrix of values.
( A matrix is a set of rows & columns. Each row represents a geologic unit and each column represents a slope category. Each cell is given a value (1-6) which represents the potential for a landslide to occur in that area. The higher the value the higher the potential for a landslide to occur in that area. )