Nightly News | January 14, 2014
>>> dennis olson of fond du lac county , wisconsin thought his garage had blown up, he called the sheriff's department in the middle of the night , they were getting a lot of similar complaints of a ground shaking boom. next day dennis got his stick and found a 100 foot crack in his drive way. geologists believe it was caused by an ice kweik. it happens when water seeps into a very frozen ground. they are most common in polar regions , they've been active, loud and forceful this year in wisconsin.