TikTok Sparks ‘Big One’ Fears After Japan Quake — What Scientists Say

After a 7.5-magnitude earthquake off Japan this week — which generated a small tsunami — social media filled with doomsday claims linking the event and a strong geomagnetic storm to an imminent West Coast megathrust quake known as the “Big One.” Experts and emergency officials say those connections are unfounded.

What Happened

On Tuesday, a 7.5-magnitude earthquake struck near the Japan Trench subduction zone, the same type of plate boundary that produced the 9.0-magnitude 2011 Tohoku (Fukushima) quake. The U.S. and Japanese agencies reported a modest tsunami along affected coasts.

Viral Claims On Social Media

Several TikTok creators hypothesized that a recent geomagnetic storm or a solar flare triggered a "non-tectonic" quake in Japan and warned that the Cascadia Subduction Zone off the U.S. Pacific Northwest would be next. One widely shared clip amassed roughly 13,000 likes and hundreds of comments. Other posts referenced a viral video of a child purportedly predicting the event — though the meaning and timing attributed to that video are disputed in comment threads.

What Scientists And Officials Say

Seismologists and emergency managers emphasize there is no credible evidence that solar storms or geomagnetic activity can directly trigger earthquakes. Geologist Bryan Castillo, who posts on TikTok as earthquakedude, addressed the rumors directly:

"No. [Cascadia] is not next. No one can tell you that."

The Oregon Office of Emergency Management (OEM) provides the following description of the Cascadia Subduction Zone:

"The Cascadia Subduction Zone is a 600-mile fault that runs from northern California up to British Columbia and is about 70–100 miles off the Pacific coast shoreline. There have been 43 earthquakes in the last 10,000 years within this fault. The last earthquake that occurred in this fault was on January 26, 1700, with an estimated 9.0 magnitude."

Experts note the date of the 1700 event is preserved in Indigenous oral histories and corroborated by tsunami damage records in Japan. On average, similar subduction events off the Oregon coast recur on roughly 500-year timescales, and OEM estimates about a 37% chance of a megathrust magnitude 7.1+ earthquake in Cascadia within the next 50 years.

Geomagnetic Storms: Real But Different

Geomagnetic storms and solar flares are real phenomena that can damage electronic systems and infrastructure — for example, by disrupting satellites, radio communications, and power grids — but they are not known to physically trigger tectonic earthquakes or directly harm people. Meteorologists and science communicators, including ABC News’ Ginger Zee, have posted explainer videos clarifying that distinction.

Other Recurring App Panics

TikTok periodically circulates similar apocalyptic content — from viral Rapture predictions to annual fears about a Yellowstone supereruption. The U.S. Geological Survey notes the Yellowstone caldera’s massive eruption occurred about 2.1 million years ago and that another comparable supereruption is not expected.

Bottom Line

Short version: a 7.5 earthquake near the Japan Trench and a concurrent geomagnetic storm sparked alarm on social media, but scientists say there is no causal link between solar activity and tectonic earthquakes. Cascadia remains a real seismic risk that officials monitor and prepare for, but claims of an imminent "Big One" triggered by this week’s events are unsupported by current science.