It's official: Metallica fans outbounced - as well as outnumbering - Iron Maiden concertgoers in last month's heavy metal duel in the Olympic Stadium in Athens.
The National Observatory's Institute of Geodynamics said in a statement Tuesday that earthquake-monitoring equipment it installed registered micro-quakes at both concerts, but Metallica's were considerably stronger.
Seismologists also found that the May 24 Euroleague basketball final next to the Olympic Stadium registered micro-quakes from crowd movements, but smaller than Iron Maiden's.
"The results highlight how seismology can record not only natural phenomena but also the effect of human activity on the environment," the statement said.
"The two concerts served as a large-scale natural laboratory where ... the Geodynamic Institute was able to study how the collective movement, rhythm and enthusiasm of tens of thousands of fans can be converted into measurable seismic waves."
