Seismologists Monitor Crowd Vibrations at Mariners’ ALDS Game

On October 6, 2025, the Pacific Northwest Seismic Network installed seismic monitoring equipment at T-Mobile Park in Seattle. This initiative aims to measure ground vibrations generated by the crowd during the Seattle Mariners’ critical American League Division Series (ALDS) Game 5 against the Detroit Tigers. This playoff matchup marks the first winner-take-all game at the stadium in 24 years.

The scientists accessed the ballpark early to position a seismometer at field level, allowing for precise measurements of potential crowd-induced vibrations. Mariners player Cal Raleigh previously noted that he felt the ground shake while rounding third base during a pivotal moment in Game 2, when Julio Rodríguez hit a go-ahead double. The installation of the seismometer is expected to provide valuable data on the extent of crowd-generated vibrations.

Historical Context of Crowd Noise in Seattle Sports

Seattle’s sports venues have a history of notable crowd noise that has been documented through seismic monitoring. In 2011, Lumen Field fans created a phenomenon known as the “Beast Quake,” registering a 2.0 magnitude reading on the Richter scale during a playoff touchdown run by Marshawn Lynch against the New Orleans Saints. Additionally, Husky Stadium recorded an astonishing 133.6 decibels during a college football game between Washington and Nebraska in 1992, a national record that lasted until 2023.

Both Lumen Field and Husky Stadium feature architectural designs that enhance and amplify crowd noise, contributing to these remarkable acoustic phenomena. The upcoming Game 5 is expected to add to this legacy.

Game Conditions and Expectations

Weather forecasts indicate rain for Game 5, requiring the roof of T-Mobile Park to remain closed. This contrasts with Games 1 and 2 of the series, where the roof was open. According to Major League Baseball regulations, if a game begins with the roof closed, it must remain so throughout the match. This enclosed environment is likely to intensify sound levels within the ballpark, creating an even more electrifying atmosphere for fans.

The Mariners aim to secure a victory against Tigers starter Tarik Skubal, who has proven challenging for them this season. The Mariners have yet to defeat Skubal in their previous three encounters. Notably, no team has managed to defeat the reigning AL Cy Young Award winner four times in a single season throughout his career.

The combination of seismic monitoring, historical crowd noise, and the competitive stakes of Game 5 promises to create an unforgettable atmosphere at T-Mobile Park. As the Mariners strive for victory, the insights gained from this unique scientific endeavor may provide a new understanding of the impact of sports crowds on their environment.