To test my hypothesis, I took a total of 26 samples from both bays, and shook them on a shake table. I used a brick with a ruler to measure the depth that a #building# that size would sink, and used that to gauge the susceptibility (to liquefaction) of the soil. The one with the most sinkage would be the most susceptible. I also subjected my soils to a uniformity test, because fine, uniform soils tend to liquefy more easily.
Soils in San Francisco Bay consistently caused the brick to sink 4 to 5 cm when water was added to the soil, whereas, in Monterey Bay soils, the sinkage varied from 0 to 5 cm, coming to a lower average than San Francisco Bay soils.
I eventually figured out that my hypothesis was correct: soils from San Francisco Bay, particularly the Marina District, are the most susceptible to liquefaction, and generally fairly uniform. Past incidents have shown ample evidence for the danger of liquefaction, such as the 6 billion dollar property cost of the Loma Prieta quake in 1989, and various collapsing bridges around both bay areas. The data suggests that it is more dangerous to build in San Francisco, primarily in the San Francisco Marina.
This project compares the soils from San Francisco and Monterey Bays and tests them for liquefaction potential to determine which area is more dangerous during an earthquake.
Science Fair Project done By Adam G. Mussell