Earthquake Risk in the Bay Area: The Hayward Fault Ellen Metzger BAESI March 23, 2013

Earthquakes in the Bay Area Can We Predict Them? Science vs. pseudoscience Short-term prediction vs. long-range forecasting. Prediction vs. prevention

Long-Range Forcasting Based on knowledge of when and where past earthquakes have occurred.  Paleoseismology – record of past offsets and recurrence interval  Seismic gaps

The Hayward Fault America’s Most Dangerous Fault? A tectonic “time bomb”

Source: USGS Forecasting (probability) vs. prediction Bay Area EQ Probabilities Hayward – Rodgers Creek Faults have the highest probabilities

Paleoseismology - the study of prehistoric earthquakes.

M Hayward earthquake 30 fatalities, 5 in San Francisco (12th most lethal US earthquake) $350,000 (>$5-100M in 2007 dollars) in damage in San Francisco alone Extensive damage in San Leandro, Hayward, and Fremont (total population less than 2000) Bay Area population was 260,000 (it is now 27 times larger) Source: USGS

1868 Hayward Earthquake ( “ The Great SF Earthquake ” ) Source: USGS 38° ° 37.5° -121°

Earthquake of M > 6.8 on the Hayward Fault ? A major earthquake today on the Hayward fault would impact more than 5 million people and Cause estimated total economic losses to residential and commercial properties would likely exceed $165 billion. Other factors, such as fire, damage to infrastructure and related disruption would substantially increase the loss

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