Why the Bears-Packers crowd made Soldier Field feel like it was shaking on Saturday

CHICAGO - Some fans at Soldier Field said the Bears-Packers playoff game on Saturday night was so loud the stadium appeared to shake.

What we know:

Several attendees and broadcasters reported feeling vibrations during the game, a sensation that has been experienced at other sporting events and concerts when large crowds cheer and jump simultaneously.

"I've done 31 games in this stadium. It's the first time I feel it shaking like this," said sports commentator Al Michaels. 

ESPN reporter Courtney Cronin said she could feel the press box shake while appearing on Chicago Sports Tonight. FOX Chicago reporter Cassie Carlson called it the best Soldier Field crowd she has experienced in four years covering the Bears.

Kevin Butler, not the former Bears' kicker, but an engineer with Henderson Engineers who specializes in acoustics and designs professional sports facilities, said crowd noise can cause structural vibrations.

"Sound is a pressure wave where it can cause materials to vibrate, so when you get 60,000 plus fans yelling, cheering, stomping, jumping around, that can add a lot of energy into the stadium and into the structure and cause vibration and feel that sensation," Butler said. 

What's next:

FOX Chicago checked with the U.S. Geological Survey and found no reports of seismic activity during the game. Seismic readings have been recorded at major events in the past, including the Marshawn Lynch "Beast Quake" game in 2011 and a Taylor Swift concert in 2023, both at the same venue.

FOX 32 has contacted the Chicago Bears for information on decibel levels at the game and is awaiting a response.