It turns out Swifties really know how to “Shake It Off.”
In July, a Western Washington University geology professor and seismologist found the singer’s shows in Seattle were on par with a 2.3 magnitude earthquake.
But that wouldn’t be the last time.
A group of scientists at Caltech and UCLA researched the seismic activity at the “Karma” singer’s Aug. 5 show at Inglewood’s SoFi Stadium for their article “Shake to the Beat: Exploring the Seismic Signals and Stadium Response of Concerts and Music Fans.”
On that evening, Swift performed in front of about 70,000 people.
“Signals were recorded on regional seismic network stations located within 9 km (about 5.59 miles) of the stadium, as well as on strong‐motion sensors placed near and inside the stadium prior to the concert series,” the publication stated.
From there, they tied the signals with individual songs and checked out the “nature of the seismic source.”
The team used spectrograms, graphs that display the “strength of various signal frequencies over time.”
“For earthquakes, most of the time they’re pretty sharp and easy to identify with waveforms, but when you have something like volcanoes where you have such a wide variety of signals, spectrograms can be really handy in helping to identify the different types of signals,” Gabrielle Tepp of Caltech explained.
The research of the SoFi show showed that each Swift song “had a distinctive tremor signal.”
“Researchers were able to identify 43 of the 45 songs played within the recorded spectrograms.”
From there, they calculated the “radiated energy of each song” and then converted it into “the local magnitude of an earthquake that would have radiated that same energy.”
The song with the largest local magnitude was Swift’s hit “Shake It Off,” which clocked in at 0.851.
“Keep in mind this energy was released over a few minutes compared to a second for an earthquake of that size. Based on the maximum strength of shaking, the strongest tremor was equivalent to a magnitude -2 earthquake,” Tepp said.
After some debate, the team concluded that it was the “dancing and jumping motions of the audience at SoFi Stadium—not the musical beats or reverberations of the sound system—that generated the concert’s distinct harmonic tremors.”
Researchers then compared Swift’s show to that of Metallica’s at SoFi. The heavy metal band performed on Aug. 25 and Aug. 27 at the stadium.
The band “had the weakest signals in terms of the strongest magnitude from each concert,” Tepp said.
“Metal fans like to headbang a lot, so they’re not necessarily bouncing,” Tepp added. “It might just be that the ways in which they move don’t create as strong of a signal.”
This study was published March 13, 2024.