Shaking It Off: The seismic impact of Taylor Swift concerts and the science behind Swiftquakes

We don't wish to be known as nothing but a news source for Swifties, but some stories are just too good to pass up: In Los Angeles last year, the fervent energy of Taylor Swift enthusiasts at SoFi Stadium sent seismic ripples through the earth's crust, prompting seismologists to take notice. Approximately 70,000 fans fervently jumped and danced to the beat of "Shake It Off," unleashing vibrations so intense that they registered as seismic activity, measuring a magnitude of 0.85. It sure makes it sound like "girl power" is really a factor, right?

Remarkably, this rhythmic upheaval persisted for several minutes, resembling the prolonged impact of a more significant earthquake. Gabrielle Tepp, leading the research team from Caltech, highlighted the prolonged duration of the trigger event shaking, emphasizing that the cumulative effect over minutes paralleled the force of a magnitude-2 earthquake. Each song performed during the concert left a distinct seismic imprint (what might be called a "concert tremor"), not dictated by the show's amplification but by the kinetic energy of the fans' movements. One supposes it adds a twist to the term "distinct harmonic tremors."

Commissioned by the California Office of Emergency Services after a similar seismic event at a Swift concert in Seattle, the study deployed sensors at SoFi Stadium, integrating the data with the state's seismic network. Out of the 45 songs performed on August 5, 2023, 43 were correlated with identifiable patterns on spectrograms.

How unique are such seismic crowds?

Not to burst Swifty bubbles too much, but this isn't quite as unique as some might think. For example, some sudies have revealed seismic activity triggered by crowd response during football games (for example). Nevertheless, it's fair to say that the "Swiftquakes" are still fairly unique. In comparison to a Metallica concert held at SoFi Stadium a few weeks later, which drew a larger crowd of nearly 78,000 attendees, the seismic impact was notably lower.

This discrepancy, Tepp explains, likely stems from the difference in audience behavior — swift, energetic dancing by Swifties proving more ground-shaking than the head-banging antics of metal enthusiasts. In other words, if metalheads want to try duplicating the effects of the Swiftquake, they'll have to try jumping more. Perhaps pogoing around in a mosh pits isn't the best idea safety-wise, but we're just objectively talking science here, people!