On Tuesday morning, an earthquake measuring 4.0 struck two miles northeast of Fremont.
The earthquake, which occurred at 2:41 a.m., struck on the border of Fremont and Union City on the Hayward Fault five miles deep; the epicenter was just north of the intersection of Niles Canyon Road and Mission Boulevard.
No significant damage was reported as a result of the earthquake.
According to ABC7News, scientists cautioned residents that a more severe earthquake is expected to strike the Hayward Fault. The area stretches from San Pablo Bay to Fremont, covering considerably densely populated areas like Berkeley, Oakland, Hayward and Fremont.
At least 13 smaller earthquakes in the area followed in the subsequent hours. Measuring between 1.0 and 2.7, these tremors struck Fremont – two of the biggest ones measuring 2.7 and 2.6 struck at 2:56 a.m. and 3:07 respectively, while the small earthquake occurred at about 6:40 a.m., as reported by U.S. Geological Survey (USGS).
— USGS (@USGS) July 21, 2015
No earthquakes measuring 3.0 or more have been reported in or around the area.
According to NBC Bay Area, An estimated 2 million people live on the Hayward Fault, which is the most heavily populated faults in California. Dr. David Schwartz, a USGS senior research geologist said that Tuesday’s tremors are “an indication the stress level is high and the plates are getting tweaked.”
The fault has been active for the last 15 years, scientists say.
Almost a year ago, a 6.0 magnitude earthquake in Napa caused considerably sever damage to life and property. One casualty was reported in the incident.
— Fremont Police Dept (@FremontPD) July 21, 2015
In 1868, an earthquake measuring 6.8 had struck the Hayward Fault. The earthquake caused widespread damage, killing 30 people and affecting property in the Bay Area, particularly the city of Hayward. It was called the Great San Francisco Earthquake until a greater earthquake swept the area in 1906.
Scientists forecast that another major earthquake is expected to strike the area – with 31 percent chance of it happening – in the next 30 years.
“It could happen in the next 30, 40 or 50 years, but we know sometime soon the Hayward Fault is going to pop,” Schwartz said.
Tom Brocher, a research geophysicist with the USGS, said, “The population is now 100 times bigger in the East Bay, so we have many more people that will be impacted.”
“We keep a close eye on the Hayward Fault because it does sit in the heart of the Bay Area and when we do get a big earthquake on it, it’s going to have a big impact on the entire Bay Area,” he said.
@abc7newsBayArea My Farmers Ins Office is on Niles Blvd. EQ knocked security cameras out of whack! The shaking knocked stuff off the counter
— Jennifers Insurance (@jennifersins) July 21, 2015
@abc7newsBayArea felt it in south San Jose. My dog woke me up and then I felt a quick jolt. My dog is probably the best warning system yet!
— Lorral_thebluecoat (@LorralWhaley) July 21, 2015
@abc7newsBayArea felt it in Oakland
— Talent (@Talentiest) July 21, 2015
According to San Jose Mercury News, inspection for track damage resulted in 30-minute delays to BART trains at 4:30 a.m. The trains were cleared around 5:30 a.m., though some delays still persisted.
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