San Francisco Bay Area - Local Scale Hazardous Setting Flashcards
What are the physical and human vulnerabilities of the place?
Physical vulnerabilities:
• The Bay area is at risk of liquefaction due to soft sediments especially between the two main fault zones of the Hayward and the San Andreas faults.
• The southern area of the San Andreas has experienced the most major earthquakes over the last 40 years.
• This map suggests San Francisco city area is physically vulnerable to liquefaction, ground shaking due it proximity to the San Andreas fault and it is over due for a large earthquake.
Human vulnerabilities:
• The San Francisco city area is home to 870,000 people
• The density of population is 18,573/sq mi
• The Golden gate bridge and the Bay bridge are designed
to withstand earthquakes but these present a risk to evacuation routes in the event of a large earthquake in the city.
What are the physical nature of the hazards in the SF Bay Area.
5 very high magnitude earthquakes since 1830
High probability of another before 2050
More shaking around areas of softer rock - landslides and liquefaction
Large seismic gaps make events hard to predict
Economic character of sf bay population
Very high median household income
Less than 10% of insurance owners have earthquake insurnace
> high incomes and quality of life despite hazard
> risk taking / trusting in management strategies
> earthquakes have high economic impacts here
Social character of sf Bay Area?
High population density - 10x that of California
High educational attainment - 40% adults over 25 have a uni degree
Desirable location despite hazard
Educated population can design effective management starts to reduce impacts
Political character of sf Bay Area
Most liberal area of country
Political unrest
(Add more in future)
Nature of hazards in California ?
Most liberal area of country
Political unrest
(Add more in future)
