A rapid and sudden shift in a slow-moving landslide in Jackson, Wyo., has residents rattled and experts looking for answers.
The down-falling movement Friday created a fracture several feet deep in the ground beneath a house in the northwest Wyoming town in, causing it to split in two.
Workers who had been striving to stabilize the 100-feet-high hillside since early April, when town officials first noticed movement, were forced to suspend their efforts. Several other homes and businesses were also threatened by the abrupt land movement.
Officials began to notice significant land changes on April 4, and by the time the ground started shifting an inch a day by April 9, authorities were forced to evacuate 42 houses and apartments in the area.
On Friday, land shift had increased to a foot a day, with flutters of rocks and dirt continuing to stream steadily down the hill.
The lurch also created surging ruptures in a road and the paved Walgreens parking lot at the foot of the hill, as well as pushing a small town water pump building about 15 feet from where it formerly stood.
Landslide specialist George Machan said at a town meeting Friday that despite the damage already caused, it is unlikely the sudden movement will cause a landslide akin to the devastation wreaked by the Oso, Wash., landslide on March 22, which killed 39 people.
Machan said geologists were still examining the cause of the ground movement and that in the meantime it is likely the earth could continue to fall, creating an ongoing threat, especially to the four homes, two apartment buildings and four businesses that lie directly below the hill in the high risk zone.
"Is it weeks, is it longer? I really don't know," Machan said. "I think it's really unpredictable how long it might take. I don't expect it to end in a day."
The AP contributed to this report.