| Sr. No. | Velocity (m/sec) | Resistivity (Ohmm) |
| 1 | 100 - 1000 | 0 - 99 |
| 2 | 1000 - 2000 | 150 - 300 |
| 3 | 2000 - 2500 | 100 - 150 |
| 4 | 2500 - 3000 | 50 - 60 |
| 5 | 3000 - 4000 | 20 - 40 |
| 6 | 4000 - 5000 | 5 - 10 |
| 7 | >5000 | 800 - 1000 |