Taylor Swift has one of the most devoted fan bases in the world — to the point that they’re now capable of causing minor earthquakes.

According to seismologist Jackie Caplan-Auerbach, Swifties who attended the Eras Tour in Seattle earlier this month caused seismic activity equivalent to a 2.3 magnitude earthquake. “I grabbed 10 hours of data from when doors opened to well after I thought the audience had gone home and I just plotted them out,” Caplan-Auerbach, who is a geology professor at Western Washington University, explained in a Wednesday, July 26, interview with Seattle’s KING 5 News.

Caplan-Auerbach decided to investigate the situation after she saw a Facebook post comparing the concerts to a 2011 Seattle Seahawks game where fans famously went wild enough to shake the ground after a Marshawn Lynch touchdown. (This incident is known as the Beast Quake.)

“The shaking was twice as strong as Beast Quake. It absolutely doubled it,” Caplan-Auerbach explained to CNN, noting that the shaking could have been caused by both the sound system and tens of thousands of dancing fans. “The primary difference is the duration of shaking. Cheering after a touchdown lasts for a couple seconds, but eventually it dies down. It’s much more random than a concert.”

Taylor Swift's Fans Are So Powerful They Cause Literal Earthquakes 2

Taylor Swift performs during ‘The Eras Tour’ concert at Allegiant Stadium on March 24, 2023 in Las Vegas, Nevada.
Casey Flanigan/imageSPACE/Shutterstock

Another seismologist, Mouse Reusch, turned the data into a sonogram to figure out which songs got the loudest response from the audience. Not so surprisingly, one of her students determined that megahits “Shake It Off” and “Blank Space” caused the most noise.

Swift, 33, played at Seattle’s Lumen Field on Saturday, July 22, and Sunday, July 23. The Saturday show broke the record for largest concert crowd at the venue, with 72,171 fans in attendance, per Swift’s team. (The previous record holder was U2, who drew more than 70,000 fans in 2011.)

Days before the Swift Quake made headlines, Swift herself thanked her Seattle fans for their memorable energy. “Seattle that was genuinely one of my favorite weekends ever,” she wrote via Instagram on Monday, July 24. “Thank you for everything. All the cheering, screaming, jumping, dancing, singing at the top of your lungs.”

The Swift Quake is just the latest memorable incident to take place during the Eras Tour, which kicked off in Arizona in March. Last month, Swift swallowed a bug mid-performance.

She went on to joke that the accidental snack was “delicious” before asking the audience, “Is there any chance none of you saw that?” She continued: “It’s fine — I’ve swallowed it. OK, so I’m just gonna try not to do as many of those. This is gonna happen again tonight, there’s so many bugs. There’s a thousand of them. Anyway, this has been fun.”