Sunday, September 28, 2025

San Francisco Rattled by 4.3-Magnitude Earthquake Overnight.

PULSE POINTS

❓WHAT HAPPENED: A magnitude 4.3 earthquake struck the San Francisco Bay Area early Monday morning, initially reported as a 4.6 by the United States Geological Survey (USGS) before being downgraded.

👤WHO WAS INVOLVED: The USGS, San Francisco Fire Department, UC Berkeley Seismology Lab, and the National Tsunami Center.

📍WHEN & WHERE: Early Monday morning, September 22, 2025, near the University of California campus in Berkeley, at a depth of 4.8 miles.

🎯IMPACT: The earthquake was widely felt across the Bay Area, but no injuries or significant damage were reported.

IN FULL

Residents of the San Francisco Bay Area were awakened by a magnitude 4.3 earthquake just before 3 AM Monday. The quake, initially reported as a magnitude 4.6 by the United States Geological Survey (USGS), was later downgraded to a 4.4 and then a 4.3. The tremor’s epicenter was near the University of California campus in Berkeley, at a depth of approximately 4.8 miles.

While the earthquake caused items to fall off counters and startled pets, the San Francisco Fire Department confirmed there were no reports of significant damage or injuries. The quake was widely felt across the Bay Area, but no significant structural impacts have been reported as of 5 AM local time.

According to the California Geological Survey, the earthquake occurred near the Hayward fault line, one of the most dangerous fault lines in the region. UC Berkeley’s Seismology Lab notes that the Hayward fault has a 33 percent chance of rupturing in a 6.7 magnitude or greater earthquake before 2043. The Bay Area as a whole faces a 72 percent likelihood of experiencing at least a magnitude 6.7 earthquake within the same time frame.

The National Tsunami Center confirmed via social media that there was no threat of a tsunami following the earthquake. The National Pulse reported in July that Southern California experienced a magnitude 4.4 earthquake in late July, with the epicenter recorded roughly four miles west of Muscoy, California, about 50 miles east of downtown Los Angeles.

Image by Lightandtruth.

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Mega Tsunami Threat Looms Over U.S.

PULSE POINTS

❓WHAT HAPPENED: The Cascadia Subduction Zone could be building toward a significant seismic event capable of producing a magnitude 9.0 earthquake and 100-foot-high tsunami along the Pacific Northwest coast of the United States and Canada.

👤WHO WAS INVOLVED: Residents of the Pacific Northwest, seismologists, and the Federal Emergency Management Agency (FEMA).

📍WHEN & WHERE: The U.S. National Seismic Hazard Model currently estimates there is a 15 percent chance of a magnitude 8.0 or higher earthquake in the Cascadia Subduction Zone in the next 50 years. The last major event occurred on January 26, 1700.

🎯IMPACT: A major earthquake in the zone could result in nearly 6,000 fatalities, with a subsequent tsunami claiming another 8,000. Additionally, the seismic event could leave well over 100,000 people injured and half a million buildings destroyed—with a total economic cost of over $100 billion.

IN FULL

The Pacific Northwest could be living on borrowed time, with the Cascadia Subduction Zone having remained geologically quiet for well over three centuries. However, the zone—which is actually an extensive fault line where the Pacific Ocean‘s Juan de Fuca Plate is being pushed under the North American Plate—has been building up pressure for decades as the oceanic tectonic plate grinds under the continental plate, and if that pressure is released, it could cause a catastrophic earthquake and subsequent tsunami.

Seismologists believe the  Cascadia Subduction Zone can, if enough pressure has built up, produce devastating earthquakes registering a magnitude of 9.0 or even higher. Geological evidence and historical accounts suggest these major seismic events only occur every 400 to 500 years—with the last major earthquake generated by the zone believed to have had a magnitude between 8.7 and 9.2 and occurring on January 26, 1700.

Despite being on the lower end of what is believed to be the historical intervals of severe earthquakes, the U.S. National Seismic Hazard Model currently estimates there is a 15 percent chance of a magnitude 8.0 or higher earthquake in the Cascadia Subduction Zone in the next 50 years. Such an event could produce a tsunami wave of over 100 feet in height, which would crash ashore from Northern California to Canada shortly after the earthquake.

The Federal Emergency Management Agency (FEMA) believes a major earthquake in the zone would result in nearly 6,000 fatalities, with a subsequent tsunami claiming another 8,000. Additionally, the seismic event could leave well over 100,000 people injured and half a million buildings destroyed—with a total economic cost of over $100 billion.

Meanwhile, the geography of the Pacific Northwest would likely be drastically altered as well, with large swaths of coastline sinking into the ocean and major estuaries flooding inland. However, despite the inevitable destruction, a major Cascadia Subduction Zone event happening sooner rather than later could be the lesser of two evils, as the longer the seismic pressure builds, the more destructive the earthquake and tsunami are likely to be.

Image by Niranjan Arminius.

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BREAKING: Tsunami Warning CANCELED After Earthquake Strikes Off West Coast.

An earthquake has struck 6.2 miles west of Ferndale, California. Initially estimated as a magnitude 6.6 earthquake, the United States Geological Survey (USGS) has since revised it to a magnitude 7. The U.S. National Tsunami Center issued a tsunami warning in response, but this has now been rescinded.

The canceled tsunami warning spanned a 400-mile stretch of the Western Seaboard, from the major Californian cities of San Francisco and San Jose all the way to Dunes City, Oregon.

Evacuation orders had been issued in multiple areas, and the San Francisco Bay Area Rapid Transit District, or BART, suspended traffic through the underwater tunnel connecting San Francisco and Oakland.

This story is developing…

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An earthquake has struck 6.2 miles west of Ferndale, California. Initially estimated as a magnitude 6.6 earthquake, the United States Geological Survey (USGS) has since revised it to a magnitude 7. The U.S. National Tsunami Center issued a tsunami warning in response, but this has now been rescinded. show more