Medium | Vp/(m·s−1) | Vs/(m·s−1) | ρ/(kg·m−3) |
Surrounding rock | 4100 | 2369 | 2365 |
Coal seam | 1800 | 1050 | 1300 |
Air roadway | 340 | 0 | 1.29 |
Collapse column | 2700 | 1560 | 2200 |