Hordes of party-minded hipsters headed out to Black Rock City this weekend for the annual Burning Man festival — possibly as many as 70,000, if past growth trends hold. And according to British seismologist Paul Denton, that's enough frenzied dancing feet to generate a small earthquake measuring about 0.5 on the Richter scale.
That conclusion is based on an experiment Denton conducted a few years ago for a BBC documentary, measuring the seismic spikes within the live concert footage of a Madness concert at the Reading music festival in southern England. It was a good choice of band, because Madness has a bit of a rep for causing so much seismic shaking at their concerts — a consequence of a style of ska-inspired dance called "skanking" — nearby residents think there must be an earthquake happening.
As some 40,000 fans danced feverishly to the up-tempo chorus of "Our House," Denton tracked the seismic readings and found they captured the ebb and flow of the dancers' activity quite nicely. Heck, you could even see the crowd's energy dwindle during subsequent choruses as they got tired. Denton pointed out in a paper last year for Astronomy and Geophysics that "Our House" came out in 1982, so "many of the band's keenest followers are now well into their forties and can no longer sustain high-energy dancing for the full two minutes of the song." Ouch. Madness fans, time to work on your cardio!
Prior to that experiment, seismologists had debated whether the noticeable increase of seismic noise near large music festivals was caused by the vibrations of the powerful sound systems, or by thousand of stomping, dancing feet. It seems to be the latter. "The amount of energy generated by people dancing is orders of magnitude larger than the amount generated by the concert's PA system," Denton told the Washington Post.
Extending those findings to Burning Man, Denton estimates that if 70,000 enthusiastic "burners" were all jumping around to the music at the same time, you'd get a pronounced spike in the seismic data equivalent to a 0.5 earthquake. It might even be helped along by the dry terrain, which is resonant enough to amplify the signal.
So, while it's not technically an earthquake per the scientific definition, those are still some good vibrations.
Image: Aerial photo of Burning Man Festival, September 2010. Credit: Kyle Harmon Reference: Paul Denton. (2014) "One Step Beyond: Festival-Induced Seismicity," Astronomy and Geophysics, Vol. 55.