Table 7 Resistivity characteristic of different rock types (after Roy and Elliot42).
From: Nature-inspired stochastic hybrid technique for joint and individual inversion of DC and MT data
Geological formation | Hydrogeological characteristics | Resistivity (Ω-m) |
|---|---|---|
Overburden (sandy soil and boulders) | Dry | 2000–12,000 |
Shale, siltstone, and clay | Aquiclude | 25–60 |
Sandy shales | Aquitard | 80–120 |
Shaly sandstones | Poor aquifer | 200–240 |
Sandstone (saturated) | Good aquifer | 280–400 |
Sandstone (unsaturated) | Dry | 750–1200 |
Sandstone (cemented) | Aquifer; probably of low yield | 600–900 |
Saltwater contaminated formations | No use or restricted use | Less than 120 |
