SEATTLE — What if the Big One happens during the Big Game?

Seattle has been bracing for a major earthquake for as far back as anyone can remember. More recently, it has been gearing up for Saturday night’s playoff between the Seahawks and the Carolina Panthers, a game that could put this sports-crazed city in contention for a second consecutive N.F.L. Super Bowl championship. Already, Seattle is awash in a blue-and-green tide of face paint, bumper stickers, pennants and earmuffs.

Now, geophysicists are connecting the dots. This week, they installed three earthquake monitors inside the Seahawks’ stadium, in what scientists say will be the first attempt to capture, almost in real time, the seismic effects of a rowdy, stomping, screaming, jumping, dancing crowd of 67,000-odd people.

The monitors are connected to the Pacific Northwest Seismic Network, which went live on Thursday with a website called QuickShake that will provide a different kind of color commentary to Saturday’s game as the sensors feed back the ground-shaking physical evidence of every big play, and big crowd emotion.