C.1 TYPICAL VALUES
The earth resistivity is commonly assumed to be 100 Ohm-meters as an average of large number of determinations. However, the earth resistivity is known to vary widely for different soil types. See Table 3.
Table 1. Typical values of earth resistivity.
|
Soil Condition |
Resistivity (Ohm-m) |
|
Sea water Swampy ground Dry earth Pure slate Sandstone |
0.1 - 1.0 10 - 100 1000 107 108 |