As Seattle Seahawks running back Marshawn Lynch slipped out of the grasp of the New Orleans Saints last week to make a 67-yard touchdown run, the 66,336 fans in the stadium made their own impressive 100-yard play though they didn't know it at the time. Their cheering and jumping shook the ground enough to register as a small seismic event on a nearby seismometer, part of the Pacific Northwest Seismic Network.
The stadium is listed in the top 10 for providing a home-team advantage. Seahawks fans are known for their game-disrupting audio track, making it difficult for the opposing team to hear the quarterback call the play. But this is the first caught recording of Seahawks causing quake-like disturbances.
Network Director John Vidale caught the action on a seismometer mounted 100 yards from the stadium. Part of the near real-time network of seismometers tracking earthquakes, tectonic, and seismic activity across the Pacific Northwest - the seismometer is strategically placed to monitor the vulnerable Alaskan Way Viaduct. The two-level overpass highway was built in 1953, before earthquake regulations in Seattle were in place. The 6.8 magnitude 2001 Nisqually earthquake damaged the viaduct, and struck during the time the stadium was under construction.