Instructions: Choose the phrase that best answers each question.
1. Examine Figures 1 and 2. Most of the earthquakes in California occur at depths of
A) 0-33 km
B) 33-71 km
C) 71-151 km
D) 151-301 km
E) 301-501 km
2. Examine Figure 1. Which of the following best describes the distribution of deep earthquakes (>151 km, blue, magenta, and red colors)
A) they never occur near earthquakes with shallow depths
B) most are located along the mid-ocean ridge system
C) they occur in linear bands around the edges of oceans
D) they have a random, not a linear, distribution
3. Examine Figure 2. Which statement best describes the distribution of earthquakes in California?
A) they are all located near the coast
B) they form several linear bands that are mostly parallel to the coast
C) they have a random rather than a linear distribution
D) they are all located near the Nevada border
4. The highest intensity of earthquake shaking in the Bay Area (Figure 3) is expected to occur
A) along the coast of the Pacific Ocean north of San Francisco
B) along the coast of the Pacific Ocean south of San Francisco
C) in the mountain ranges between the coast and San Francisco Bay
D) along the edges of San Francisco Bay
5. The youngest seafloor (red color in Figure 5) occurs
A) in patches along the edges of continents
B) in linear bands in the centers of oceans
C) in the northwest part of the Pacific Ocean
D) in the Arctic Ocean
Instructions: Write short answers for the following questions. Answers will be graded credit / no credit; results will be available several days after the exercise due date.
1. In class we have been examining features that are found on the seafloor. Near which feature are the deep earthquakes found (see Figure 1 and you could also look at pg 52 in the textbook).
2. Look at distributions of earthquakes in Figure 2. Why do you think they are arranged in linear bands, as shown in this figure?
3. (A) What is the location of the earthquake you selected at the USGS-NEIC web site? (B) Look at the seafloor map distributed to you in class to see if the earthquake corresponds with a seafloor feature.
4. As well as you can, find the location where you live on Figure 4 or on another map you get through the ABAG site. Where do you live and what is the expected intensity of shaking where you live?
5. What pattern do you observe in the distribution of seafloor ages (Figure 5)?