# Describe (facts) how P and S-wave velocities change

Pick the best bold answer for numbers 1-12.

1. The Earth is a/an open or closedsystem as far as energy is concerned and a/an open or closed as far as “rocky” material (10 points).
2. Divergent boundaries experience tensional, compressional, or shearing forces creating normal, reverse, or strike-slip faults (10 points).
3. Convergent experience tensional, compressional, or shearing forces creating normal, reverse, or strike-slip faults (10 points).
4. Transform boundaries experience tensional, compressional, or shearing forces creating normal, reverse, or strike-slip faults (10 points).
5. Are The Himalayas an example of a convergent, divergent, or transform boundary (5 points)?
6. Is the Mid-Atlantic Ridge an example of a convergent, divergent, or transform boundary (5 points)?
7. Is the San Andreas Fault an example of a convergent, divergent, or transform boundary (5 points)?
8. Is Mount St. Helens (The Cascade Range) an example of a convergent, divergent, or transform boundary (5 points)?
9. Is the Marianas Trench an example of a convergent, divergent, or transformboundary (5 points)?
10. Is the East African Rift Zone (The Red Sea) an example of a convergent, divergent, or transform boundary (5 points)?
11. The San Andreas Fault is a right or left-lateral strike-slip fault (5 points).
12. The North Anatolian Fault is a right or left-lateral strike-slip fault (5 points).

Write out the following short answer questions in complete sentences.A.

A. Describe (facts) how P and S-wave velocities change as they travel through the interior of the Earth from about 0 to 3,000 km, at approximately 3,000 km, and then afterwards (at least 3 sentences, 5 points).

B. Interpret (the why) the P and S-wave velocities change as they travel through the interior of the Earth from about 0 to 3,000 km, at approximately 3,000 km, and then afterwards (at least 3 sentences, 5 points)).

C. Describe and interpret the P and S-wave shadow zones (At least 3 sentences, 5 points).

D. If a sample contains 12.5% Parent, how many half-lives have passed? If the radioactive pair is K-40 and Ar-40, what is the actual age of the sample? (5 points)