In Los Angeles, Taylor Swift’s fans made such a powerful impact last year, it’s as if they literally moved the earth beneath them.
During a concert at SoFi Stadium, around 70,000 fans got so into the song “Shake It Off” that their collective jumping and dancing created tremors. These tremors were so significant, they measured a magnitude of 0.85, similar to an earthquake.
The intensity of these vibrations didn’t just flicker and fade; they sustained for several minutes. This prolonged activity showcased the force equivalent to a much stronger earthquake.
Gabrielle Tepp, who leads the research team at Caltech, explained the phenomenon. She noted that the energy from the fans was released over a few minutes. This is unlike a typical earthquake of similar magnitude, which releases its energy in just a second. The peak of the tremors reached what would be considered a magnitude-2 earthquake.
Interestingly, each song performed at the concert had its own unique seismic signature. This wasn’t due to the loudness of the music or the bass from the speakers, but rather the fans’ enthusiastic jumping and dancing. The researchers were able to match 43 out of the 45 songs played that day to specific patterns on their spectrograms.
This study came about after the California Office of Emergency Services requested it. Their interest was piqued following a Taylor Swift concert in Seattle. That event reportedly generated tremors equivalent to a 2.3 magnitude earthquake in July 2023.
To gather their data, the Caltech team set up sensors at SoFi Stadium. They then paired this data with information from the state’s existing regional seismic network.
The team also looked at how a Metallica concert at SoFi, which occurred a few weeks after Swift’s, compared in terms of ground shaking. Despite having a higher attendance, with almost 78,000 fans due to additional standing-room sections, the Metallica concert generated less ground shaking.
Gabrielle Tepp pointed out that this difference isn’t about the loudness of the concerts or the enthusiasm of the fans. It seems that the specific movements of head-banging by Metallica fans don’t create as much ground movement as the dancing and jumping by Swift’s fans.
This unique study highlights the unexpected ways in which music and fan enthusiasm can interact with our physical world.