Rockiness | Density Kg/m3 | Bulk modulus GPa | Shear modulus GPa | Internal Cohesion MPa | Angle of internal friction ˚ |
Medium-grained sandstone | 2580 | 3.3 | 2.5 | 4 | 37 |
Coal | 1410 | 2.5 | 1.1 | 1 | 25 |
Sandy mudstone | 2400 | 5.6 | 3.8 | 2 | 36 |
Mudstone | 2400 | 5.6 | 3.8 | 1.2 | 36 |