Published On: Tue, Oct 15th, 2019

California earthquake: Why does Bay Area get so many earthquakes? | World | News

The San Francisco Bay Area is a region in North California, encompassing the city of San Francisco and its surrounding areas. While San Francisco is a tourism spot, known for its iconic Golden Gate Bridge and its cable cars, the city is also a well known earthquake hotspot.

On Monday at 10.33pm local time this week, an earthquake shook the San Francisco Bay Area. 

The epicentre was located at the Pleasant Hill and Walnut Creek areas.

Why does the Bay Area get so many earthquakes?

The San Andreas Fault is a continental transform fault, or plate boundary, which runs some 750 miles through California. 

READ MORE: Typhoon Hagibis and Japan earthquake: Can storms trigger earthquakes?

The San Andreas Fault is the tectonic boundary between the Pacific Plate and the North American Plate.

The fault divides into three segments, the most significant being the southern segment which passes within about 35 miles of Los Angeles.

Monday’s earthquake occurred along the Calaveras Fault, which is one major branch of the San Andreas Fault System.

California is also located on the Ring of Fire, a horseshoe-shaped area in the Pacific Ocean – where the majority of the world’s earthquakes and volcanic eruptions occur. 

The U.S. Geological Survey currently state on their website: “Based on models taking into account the long-term rate of slip on the San Andreas fault and the amount of offset that occurred on the fault in 1906, the best guess is that 1906-type earthquakes occur at intervals of about 200 years.

“Because of the time needed to accumulate slip equal to a 20 ft offset, there is only a small chance (about 2 percent) that such an earthquake could occur in the next 30 years, according to the report of the Working Group on California Earthquake Probabilities.

“The real threat to the San Francisco Bay region over the next 30 years comes not from a 1906-type earthquake, but from smaller (magnitude about 7) earthquakes occurring on the Hayward fault, the Peninsula segment of the San Andreas fault, or the Rodgers Creek fault.”

Source link