Taylor Swift is known to have an energetic fan base, but just how much energy can 70,000 Swifties generate? A group of scientists in California may have an answer based on earthquake-like signals from her Los Angeles Eras Tour concert at SoFi Stadium on Aug. 5, 2023.

After Swift’s concerts at Seattle’s Lumen Field in July caused seismic activity, a California Institute of Technology research team sought to better understand what causes “concert tremor.” The team recorded vibrations from motion sensors it set up near and inside SoFi Stadium as well as regional seismic network stations and was able to detect 43 of the 45 songs Swift performed during her concert. 

By calculating the energy radiated during each song at the Los Angeles concert, the Caltech researchers could interpret each as a local magnitude of an earthquake that would have radiated the same energy, according their research article, published in Seismological Research Letters on March 13.

With these calculations, the study found the most energetic signals during these songs:

• “Shake It Off” with a local magnitude of 0.851
• “You Belong with Me” with a local magnitude of 0.849
• “Love Story” with a local magnitude of 0.800
• “Cruel Summer” with a local magnitude of 0.741
• “22” with a local magnitude of 0.645

The energy released during each song is over a few minutes, rather than a second in the case of an earthquake, explained Gabrielle Tepp, a staff seismologist at the Caltech Seismological Laboratory who oversaw the study. “So the magnitude calculated from the maximum amplitude of shaking is much lower (about -2),” she told CBS News.

The researchers determined that crowd motion was the primary source of the concert tremor signals, not the speaker system and instruments.

They also analyzed three other concerts at SoFi in the summer of 2023: Morgan Wallen, Metallica and Beyoncé.

“Overall, the results from these concerts are similar to those from the Swift concerts and support the audience-source hypothesis,” the research article says. “The (local magnitude) of the songs was in the same range as the Swift concerts, although none matched or exceeded the strongest Swift signal.”

Swift’s Eras Tour has broken multiple records, including becoming the first to gross over $1 billion, according to Pollstar. Swift is currently on a brief break from shows, with the tour starting again on May 9 in Paris after the release of her eleventh studio album, The Tortured Poets Department, on April 19.