September 22, 2025
2 min learn
San Francisco Rattled by Predawn Earthquake
The San Francisco Bay Space was rattled early this morning by a magnitude 4.3 earthquake alongside the Hayward fault line
USGS/CISN: Northern California Seismic System (UC Berkeley, USGS Menlo Park, and Companions)
Sleeping residents of California’s San Francisco Bay Space have been rattled awake by a magnitude 4.3 earthquake within the early morning hours of September 22.
The earthquake struck 1.25 miles east-southeast of Berkeley, Calif., with shaking felt as far-off as Salinas, Calif., about 100 miles to the south, and Chico, Calif., about 150 miles to the north. The temblor doesn’t pose any tsunami menace, in response to the Nationwide Tsunami Warning Heart.
The epicenter of the earthquake was about 4.7 miles deep, in response to a preliminary report from the U.S. Geological Survey. The company’s evaluation is constant, however specialists have tentatively linked the occasion with 10 different smaller quakes, principally too weak for folks to note, which have rattled the area throughout the previous month.
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The earthquake occurred close to the Hayward fault line, which runs from the north aspect of San Francisco Bay to southeast of San Jose. The biggest recognized earthquake on file within the space of this fault was a magnitude 6.8 occasion in 1868.
The earthquake scale is logarithmic, not linear, so the historic quake launched greater than 5,600 occasions extra vitality than this morning’s occasion. By comparability, San Francisco’s lethal 1906 earthquake, which occurred alongside the San Andreas fault, was no less than a magnitude 7.7 occasion.
Due to its historical past, the Hayward fault has been rigorously watched by scientists, who fear that the now densely populated area might see rather more severe injury the following time a really sturdy earthquake strikes.
Thus far, almost 26,000 folks have reported feeling Monday’s quake by means of USGS’s “Did You Really feel It?” reporting instrument, which gathers on-the-ground information in regards to the depth and results of earthquakes. In case you are within the Bay Space—whether or not you felt the temblor or not—you possibly can fill out the company’s kind to contribute to observations.
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