pg 10
Seismic Velocities of Earth Materials
The P and S wave velocities of various earth materials are shown below:
| Material | P wave Velocity (m/s) | S wave Velocity (m/s) |
|---|---|---|
| Air | 332 | |
| Water | 1400-1500 | |
| Petroleum | 1300-1400 | |
| Steel | 6100 | 3500 |
| Concrete | 3600 | 2000 |
| Granite | 5500-5900 | 2800-3000 |
| Basalt | 6400 | 3200 |
| Sandstone | 1400-4300 | 700-2800 |
| Limestone | 5900-6100 | 2800-3000 |
| Sand (Unsaturated) | 200-1000 | 80-400 |
| Sand (Saturated) | 800-2200 | 320-880 |
| Clay | 1000-2500 | 400-1000 |
| Glacial Till (Saturated) | 1500-2500 | 600-1000 |
Unlike density, there can be a large variation in seismic velocity between different rock types and between saturated and unsaturated soils. Even with this variation, however, there is still considerable overlap in the measured velocities. Hence, a knowledge of seismic velocity alone is not sufficient to determine rock type.
Seismology
- Simple Earth Model: Low-Velocity Layer Over a Halfspacepg 11
- Head Wavespg 12
- Records of Ground Motionpg 13
- Travel-time Curves for a Simple Earth Modelpg 14
- First Arrivalspg 15
- Determining Earth Structure from Travel Timespg 16
- Derivation of Travel Time Equationspg 17
- High-Velocity Layer Over a Halfspace: Reprisepg 18
- Picking Times of Arrivalspg 25
- Wave Propagation with Multiple Horizontal Layerspg 26
- Travel Time Curves from Multiple Horizontalpg 27
- Hidden Layerspg 28
- Head Waves from a Dipping Layer: Shooting Down Dippg 29
- Head Waves from a Dipping Layer: Shooting Up Dippg 30
- A Field Procedure for Recognizing Dipping Bedspg 31
- Estimating Dips and Depths from Travelpg 32