The electrical resistivity of rock is a property which depends on lithology and fluid content. The resistivity of
coarse-grained, well-consolidated sandstone saturated with fresh water is higher than that of unconsolidated silt of
the same porosity, saturated with the same water. Also, the resistivities of identical porous rock samples vary
considerably according to the salinity of the saturating water. The higher the salinity of the water, the lower the
resistivity of the rock.