Answer Key - Assignment 12 Earthquakes

1.  How does the fault structure in Southern California and Northern California differ from one another?

In Southern California, all of the plate movement is on one structure. In the Bay Area, there are many faults, like the branches of a tree.

2.  What is considered to be the most dangerous fault in the Bay Area?

The Hayward Fault

3.  What do scientists believe is the average time between earthquakes on the Hayward Fault?

The average period between earthquakes on the Hayward Fault is 130 years.

4.  How many road closures are expected to occur on the Hayward fault after a large earthquake?

1700 road closures are expected

5.  How fast is the Calaveras fault creeping each year?

The Calaveras fault creeps 14 or 15 mm per year or more than 1/2 inch

6.  What type of fault is the San Andreas?

The San Andreas is a strike-slip sometimes called a transform or a transcurrent fault.

7. How does the construction of new concrete buildings differ from old concrete buildings when it comes to earthquakes?

New concrete buildings flex with earth movement. Old buildings are brittle and tend to break.

8. Where does the San Andreas fault originate (in the south?

The San Andreas fault originates in the Salton Sea

9.  What was the location of the largest earthquake in California history?

The largest earthquake in California history was in Fort Tejon

10. Where was the location of the rupture that caused the Loma Prieta earthquake?

The Loma Prieta rupture occurred in the Santa Cruz mountains near Summit Road

11. What major sporting event was taking place as the Loma Prieta earthquake occurred?

The World Series

12. How many fires did the Loma Prieta earthquake trigger in San Francisco?

27 fires were triggered

13.Why did one section of the freeway in Oakland collapse during the Loma Prieta earthquake while another section remained standing?

All of the sections of the freeway built on fill collapsed. Those  built on natural terrain did not.

14. How much bigger than the Loma Prieta earthquake is the next large earthquake closer to S.F. expected to be?

The next quake in SF is expected to be 50 times  bigger than the Loma Prieta.

15. What street does the video focus on at the end?

California Street