The stamping feet of 50,000 Foo Fighters fans literally shook the earth under Auckland, seismic tests show.
Geonet today said seismic stations set up in Herne Bay and Eden Park recorded ground movement similar to a volcanic tremor as the band played through their nearly three-hour set at Western Springs on Tuesday.
The first vibrations were recorded around 7:30pm, part way through the set of support band Tenacious D.
But the biggest shakes came after the Foo Fighters took to the stage at about 8:20pm.
Concert vibrations were recorded at 3Hz, with the ground shaking three times per second in a regular rhythm.