Type | Resistivity (Ohm metre) |
Sea water | 0.1 - 1 |
Garden soil/alluvial clay | 5 - 50 |
Clay | 5 - 100 |
Clay, sand and gravel | 40 - 250 |
Porous chalk | 30 - 100 |
Quartzite/crystalline limestone | 300+ |
Rock | 1000 - 10,000 |
Gneiss/igneous rock | 2000+ |
Dry concrete | 2000 - 10,000 |
Wet concrete | 30 - 100 |
Ice | 10,000 - 100,000 |