1. Why is it often necessary to employ more than one geophysical technique or other geologic information (well logs) in order to characterize the subsurface? Give an example.

2. What are the approximate P-wave velocities for air and water. Give a physically meaningful explanation for the difference.

3. For a P-wave in the slow medium with a 30° angle of incidence, sketch all waves generated at a horizontal interface. Clearly indicate whether the angle of generated waves is larger, smaller or the same as the incident wave.

4. Sketch/describe analog and digital recording of seismic data. What are the advantages/disadvantages of each method?

5. For a single horizontal interface sketch/describe why head wave arrivals should plot as a straight line (hint: use ray paths from source to 2 or more geophones). How can velocity be determined from this information?

6. Give two examples of when a seismic refraction survey might miss a layer?

7. Give the definition for Normal Move Out. Sketch/describe how Normal Move Out appears on reflected arrivals (geophone traces).

8. Sketch/describe how the dip of an interface can be determined from a reflection survey. Clearly indicate what observations are required to determine dip. Note there are 3 separate methods for determining dip. Choose just ONE!
 
 

When using equations please define all terms (e.g., E = Young's Modulus)