# Homework 1

- Due Jan 10, 2020 by 11:59pm
- Points 15
- Submitting on paper
- Available Jan 6, 2020 at 12am - Jan 20, 2020 at 11:59pm 15 days

From Introduction to Seismology,

- Read section 2.2
- Read Appendix B.2 and Appendix E

Do the following exercises:

- Section 2.4, p. 33: exercise 3., reproduced here because not available in the 1999 edition:

3. Figure 2.5 shows a vertical-component seismogram of the 1989 Loma Prieta earthquake recorded in Finland. (a) Estimate the dominant period, T, of the surface wave from its first 10 cycles. Then compute the frequency *f=1/T. (b) *Make an estimate of the maximum surface-wave strain recorded at this site. Hints: 1 micron = 10^{-6} m, assume the Rayleigh surface wave phase velocity at the dominant period is 3.9 km/s, remember that strain is du_{z}/dx, Table 3.1 may be helpful.

- Section 3.8, p. 60: exercises 1 and 2. (in the 1999 edition: exercise 1. is on p.34: 3.1). Reproduced exercise 2 here because it is missing from the 1999 edition:

2. Figure 3.7 plots a harmonic plane wave at t = 0, traveling in the *x* direction at 5 km/s. (a) Write down the sine function that describes displacement *u*, as a function of *x* and t. (b) Write the corresponding equation using the cosine function. (c) What is the displacement at 6 km and t = 30s? (d) What is the maximum strain for this wave?

Show your work. Hand your work in at the beginning of class on Friday January 10, 2020. Don't forget your name!