In hilly terrain, the slope or inclination plays the dominant role
in land-use planning. The lower-slope sites are optimal for the
station location. The slope facing the sun is more suitable as the
seismic station can be best powered by a solar-panel. The aspect
(the slope direction) was used to model the orientation of the
topography relative to the direction of the sun. The raster slope
layer was generated using the GRID module in ArcInfo using the
slope command. This command fits an inclined plane at each cell
center to represent the maximum rate of change of elevation
among the surrounding 3 3 cell block. The slope value of this
plane was calculated using the average maximum technique
(Burrough and McDonell, 1998). The direction the plane faces is
the aspect for the processing cell. The slope map (Fig. 4b) presents
this information by displaying the distribution of the numerical
value of the varying slope degrees of the land surface within the
study area. The value of the output raster is the compass direction
of the aspect (Burrough and McDonell, 1998). Fig. 5a illustrates the
spatial distribution of the aspect grid in the study area. It is worth
noting that the slope and aspect were considered important
parameters through which the geological conditions suitable for
the seismic stations are reached.