Tuesday, 27 May 2014

Three feared dead after Colorado landslide.

Three men are feared to have died after a massive landslide in Messa County, Colorado, on Sunday 25 May 2014. Clancy Nichols (51), his son Danny Nichols (24) and Wes Hawkins (46) set out in a four-wheel drive vehicle to discover the cause of a disrupted irrigation system on a ranch in the Collbran-Mesa area and have not been seen since. Firefighters from the Plateau Valley Fire Department sent to investigate after witnesses reported hearing a sound 'like a freight train' discovered a 4-5 km section of hillside on Grand Mesa, had collapsed in the area where the men went missing. It is thought that the hillside may have been moving for much of the day, disrupting the irrigation system, but underwent a sudden collapse while the men were on the hillside. The resultant mudslide is 6-10 m deep at its edges and feared to be as much as 60 m deep in the middle.

The 25 May 2014 Messa County landslide. Solomon Banda/Associated Press.

The landslide is believed to have been triggered by runoff from Grand Mesa following two days of strong rain. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. Levels of rainfall recorded in communities near the area were not exceptionally high this weekend, but higher levels of rainfall may have occurred on the mountain itself. 

Grand Mesa is the world's largest flat-topped mountain, covering an area of 1300 km² between the Colorado and Gunnison Rivers in western Colorado. The Mesa rises about 1800 m above the surrounding plains and averages 3400 m above sea-level. Much of its top is covered by forests and lakes.

The approximate location of the 25 May 2014 Grand Mesa landslide. Google Maps.

See also...

Five hikers have been killed and a teenage girl suffered a broken leg after a rockfall hit a viewing station overlooking Agnes Vaille Falls in Chalk Creek Canyon in Chaffee County, Colorado, on Monday 30 September 2013. Around 100 tonnes of rocks, some described as...

At least two major oil spill have occurred in the Wattenberg Oil Field in Colorado following extensive flooding in the state this week. On...

Five people have been confirmed dead flooding in Colorado, four in...

Follow Sciency Thoughts on Facebook.

No comments:

Post a Comment