From The Denver Post (Jesse Paul):
“Our results revealed that the rock avalanche was a cascade of landslide events, rather than a single massive failure,” said the study led by Jeffrey Coe, a research geologist with the U.S. Geological Survey.
The 2.8-mile-long West Salt Creek landslide on the Grand Mesa on May 25, 2014, was the longest such slide in Colorado history.
The report found the sequence began with an early morning rockfall event that combined with a later earth failure.
The slide near the town of Collbran lasted about 3.5 minutes and sent a wall of debris rocketing down from the Grand Mesa…
Worries of another catastrophe have persisted in the slide’s wake, particularly in June, when heavy rains prompted warnings. The main risk, officials say, is in early spring as snowmelt travels down the slide area.
Water that has collected in a depression near the top of the slide has created a “sag pond,” which continues to prompt fears among geologists of another catastrophe.