Thirty-five minutes into their 17 June 2018 World Cup debut, the Mexican national team scored a goal against the defending champion German national team, propelling the underdogs to a remarkable upset that shook — literally, some would say — Earth itself:
The Institute of Geological and Atmospheric Investigations said highly sensitive earthquake sensors registered tremors at two sites in Mexico City, seven seconds after the game’s 35th minute, when star player Hirving Lozano scored. It called the tremors an “artificial” quake.
Though the game occurred thousands of miles away in Russia, some of the celebrations that occurred in Mexico City reportedly triggered seismometers that are part of the Mexican Seismic Monitoring System:
The [earthquake] detected in Mexico City originated artificially. Possibly by massive jumps during the goal of the selection of #México in the World Cup. At least two sensors inside the city detected it at 11:32.
"Such events are not very large at all; only sensitive (and generally close) seismographic equipment can detect the effects of the crowds," the Institute of Geological and Atmospheric Investigations added in a blog post. The sensors in question were located in two different neighborhoods in Mexico City: Venustiano Carranza and Coyoacán.
This would be far from the first time seismic blips have been linked to sports jubilation. It turns out that if you place a remarkably sensitive instrument designed to detect vibrational movement directly adjacent to a large stadium (or other areas of likely jubilation), those instruments can sometimes pick up the rumblings of activity likely sourced from that area. (They can also pick up, in point of fact, the motion of cars, the movement of waves, and the passage of wind.)
Well-publicized "earthquakes" linked to activity within the Seattle Seahawks’ CenturyLink Field — for example — are likely the result of the stadium’s proximity to a seismological station, one of which is located "a block or so" away. An instrument there recorded activity during an 8 January 2011 game in which Marshawn "beast mode" Lynch’s game-winning touchdown versus the New Orleans Saints may have caused what the media (as well as some in the scientific community) dubbed a "beast quake."
A 2017 paper in Scientific Reports discussed other notable examples of "footquakes" caused by sport celebrations, and each of these examples necessarily included data from close-proximity stations:
Seismic recording of people moving to celebrate goals or relevant plays during sport events have been reported episodically, both in soccer and American football. A college American football game played in Louisiana on October 1988 was recorded seismically [on an on-campus seismograph in a building around 300 m away from the stadium] and is since then known as the “Earthquake Game”. [...]
In the case of soccer, the first reported example of seismic records of fans celebrations is the so-called “Gol del terremoto” (Earthquake’s Goal), recorded in 1992 by a seismometer of the Observatorio Astronómico La Plata (Argentina), located about 600 m away from the football stadium. [...]
Recent examples of seismic records [from a station 500 m from the stadium] of crowds celebrating soccer goals were presented last year by the University of Leicester and the British Geological Survey and had a significant impact in social networks, including a dedicated Twitter account (@Vardyquake). The ICTJA station regularly record this kind of “footquakes” generated by people shaking to celebrate goals at the FC Barcelona stadium, hosting up to 90000 persons during first level games.
The seismic activity recorded during Mexico v. Germany in the first round of the 2018 World Cup would also not be the first documented instance of seismic activity recorded by people celebrating remotely, as opposed to those celebrating at the actual event:
During a temporary broad-band [seismometer] deployment in Cameroon in 2006, tremor like signals recorded simultaneously all around the country surprised a research team carrying on a seismic exploration project in the country and were finally attributed to the lively celebrations of people watching television broadcasts of the National Football Team in the 2006 African Cup of Nations.
Not everyone is convinced that the Mexico seismicity records the effects of large-scale jubilation, however. Xyoli Pérez Campos, who heads Mexico’s Servicio Sismológico Nacional, told National Geographic that the signal did not appear similar to any kind of earthquake, natural or man-made. "It was probably a person, or people, jumping up and down next to the [seismology] station," he said.
Headlines linking seismic activity to sporting events, in general, are overblown because they necessarily require the definition of "earthquake" to be extremely broad and — also by necessity — rely on measurements taken directly near the event. In many cases, the stadiums reporting on the earth-shaking nature of their fan base —CenturyLink Field, for instance — have installed seismometers inside the stadium explicitly to test the influence of their cheering fans. Legitimate earthquakes, on the other hand, can be detected hundreds to thousands of miles away from their sources.
Seismologist Jordi Diaz, who authored the 2017 Scientific Reports paper and who works at the Institute of Earth Sciences Jaume Almera (ICTJA) in Barcelona, Spain, described calling such events earthquakes “language license” to Vice News following a reported soccer earthquake in Barcelona:
Diaz says that referring to all of these things as an "earthquake" is a "language license," although they are all caused by the same resulting seismic waves. Still, you can get the same effects by having a bunch of kids jump up and down, as he often does when visiting local schools.
This would be different than a true earthquake, whose vibrations could travel hundreds to thousands of miles through Earth before being registered by a seismometer. To make this point, Diaz tweeted a comparison of the profile of the vibrations caused by a March 2017 Barcelona soccer goal registered 500 meters away (red) to a 4.3 Mw earthquake (black) recorded by the same station but whose epicenter was 350 kilometers away:
While sporting events can — like many other things — trigger blips on a seismometer, not everything that blips is in the same league as a true earthquake.