Mexico’s victory over Germany in an early World Cup game on Sunday caused quite the stir in Mexico City. At 11:35 am, when Hirving Lozano scored the game-winning goal at a match in Russia, seismometers in Mexico City picked up a spike in seismic activity. Mexico’s Institute of Geological and Atmospheric Research claims these tremors were caused by thousands of soccer fans jumping up and down in celebration, but some scientists are not so sure.
“It was probably a person, or people, jumping up and down next to the [seismology] station,” says Xyoli Pérez Campos, who heads Servicio Sismológico Nacional (SSN), Mexico’s national seismological service. Campos says the vibrations picked up by the seismometers do not resemble an earthquake, man-made or otherwise.
“It wouldn’t look like a single peak.”
When sections of the Earth’s crust slip beneath or past one another, energy is released in the form of seismic waves. Seismologists use sensitive instruments called seismometers to detect these waves as they travel through the Earth’s interior. Scientists can determine the source of a quake by examining its seismic wave pattern.
“People [jumping] can generate vibrations, but they look very different on the record than an earthquake,” says Campos.
Seismometers have picked up sounds and vibrations from boisterous crowds before, but no synchronized celebration has ever been able to trigger a true seismic event, according to William Yeck, a geophysicist with the U.S Geological Survey.
The term “man-made earthquake” is typically used to describe quakes catalyzed by human activity such as fracking, drilling, and nuclear testing.
“It is possible for humans to cause earthquakes, there’s no question about that; it’s just in this case with people cheering, it doesn’t look like that’s what happened,” says Yeck.
Tens of thousands of earthquakes, natural and man-made, shake the surface of our planet every year, most of which are low on the Richter scale (and thus small). But more than a dozen quakes above magnitude 4.0 have devastated communities across the globe this year, including the 6.1 magnitude earthquake that struck the Japanese city of Osaka this morning, killing four and injuring more than 300.