1. Define and contrast plane stress and plane strain, using both words and equations for the appropriate conditions. Draw diagrams illustrating the differences in physical interpretation. Give an example from structural geology or tectonics of a process or phenomenon explainable under the plane stress assumption, and an example explainable under the plane strain assumption.

2. Discuss the conditions under which a rock may respond elastically to stress. (Note: simply stating ``high strain rates or cold temperatures'' is not enough although aspects of these may appear in a correct answer.)

3. Write two simple equations that express stress as some function of strain; a) for linearly elastic materials; and b) for linearly viscous materials. Your equations should contain nothing more than sigma for stress, epsilon for strain, a time derivative, and two material constants.

4. Use your equation for the linearly viscous material to derive the units of viscosity in the MKS system. Show your entire dimensional analysis.

5. Discuss the conditions under which a rock may respond plastically to stress. Identify what parts of the stress-strain curve are plastic.

6. Discuss the conditions under which a rock may respond in a viscous manner to stress. Identify what parts of the stress-strain curve are viscous or frictional.

7. Define Young's modulus and describe how it can be estimated. For what geologic situations might you want to use this parameter?

8. Sketch and describe the modes of failure of a concrete building support column where a) it has little or no lateral steel reinforcement; and b) it has substantial steel reinforcement (but still fails). Which failure has Mode I fractures, and which has Mode II fractures?

9. Consider the 1857 San Andreas fault rupture, which extended from the Carrizo Plain in central Calif. to Cajon Pass in southern Calif., and to 15 km depth. Was it a strike-slip or dip-slip earthquake? Sketch a rough map, and show where you would find a) the Mode II parts of the rupture; and b) the Mode III parts of the rupture.

10. Consider the Genoa fault zone, which extends from southwestern Carson Valley to downtown Reno. Assuming it dips 45 degrees east and ruptures in a magnitude 7.2 purely normal-slip earthquake, describe where you would find a) the Mode II parts of the rupture; and b) the Mode III parts of the rupture.

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