On Tuesday night, the Foo Fighters were playing at Western Springs Stadium in Auckland NZ, and something quite unexpected occurred. According to the GeoNet blog post, two seismic stations in the Aukland GeoNet seismic network, respectively located at 1.5 and 2 km from the stadium, recorded a strong low frequency signal around 7:30 pm, and a strongest one at 8:20 pm, exactly when the Foo Fighters took the stage.
Until the concert ends at 11 pm, ‘vibrations were recorded as a semi continuous harmonic signal with a peak osculation of 3Hz, ie the ground was shaking 3 times per second in a nice rhythmic motion’.
Geologists think that the cause of all this shaking was the weight of the 50,000 fans dancing during the songs when the signals peaked. That’s pretty incredible, but apparently 50,000 New Zealanders jumping at the same time, represents a huge amount of weight, powerful enough to shake the earth.
They said that the signal was similar to a volcanic tremor, but the synchronization with the Foo Fighters’ gig, doesn’t leave a doubt, it was indeed due to the fans attending the concert.
Not bad, but I thought that New Zealand had already enough natural earthquakes without having to bear those induced by Dave Grohl and his band!