A magnitude 4.0 earthquake shook up San Francisco Bay Area early Monday morning at 6:49 local time, just a kilometer from Piedmont, which also experienced a magnitude 4.0 earthquake just a day ago. So far, no injuries have been reported, but the quake did jolt up a number of people from their sleep and gave those who are already on the road quite a scare.
BART is okay
Meanwhile, the Bay Area Rapid Transit (BART) has said that there was no damage round along the tracks or yards following the quake. Just the same, they held the trains for inspections before letting them move again. At the same time, there were some “major delays” following the quake as well as a medical emergency and a couple more issues.
The Hayward Fault
According to the U.S. Geological Survey, the recent quake actually originated from The Hayward Fault. It runs from San Pablo Bay in the north all the way to Fremont in the south while passing a number of cities including Berkely, Oakland, Hayward and Fremont.
The Hayward Fault is said to be a mostly right lateral, strike slip fault with a creep of about 1/5 of an inch each year. Meanwhile, the 2003 Working Group of California Earthquake Probability had given the Hayward Fault a slip rate of about 9mm/year or 1/3 of an inch. This means that the said fault takes on stick-slip movement of about 4 mm/year, which leads to earthquakes.
The last deadly earthquake in San Francisco was brought about by the San Andreas Fault back in April 1906. The said earthquake had a magnitude of 7.9.