Mammoth and Mastodon cache in the Colorado Mountains

4 Nov 2010

The mountains of Colorado are not recognised as a haunt of mammoth or mastodon - but they are digging them up at a reservoir near a ski resort (see www.aspendaily.com/print/143477 ). The reservoir had been drained and the bottom was being dug out by bulldozers when the bones were found - and the search is being expanded. Mastodons are usually found in eastern North America. In addition, a complete juvenile mammoth was found intact buried in silt. The reservoir was built in 1965 from what had been a wet depression in the mountains. All that was required was a small earth dam. However, the village has grown as the ski resort has prospered and now the reservoir is being udated - enlarged and a proper dam built. After draining the water they first came across a layer of muck and below this was a thick layer of red clay. This acted like a seal and protected what was below. This began with a deposit of peat that was rock free, light and dry. It wasn't wet peat. Under the peat, which was about three feet thick, they found a deposit of gooey black silt, also free of rocks and boulders, and it is in this that the bones are being found. Beneath this deposit there was another layer of reddish soil but it contained rock debris and resembles the constructs of glacial moraines. The red clay seal has preserved not just mammoth and mastodon bones but woody material and plant remains that it is hoped will help to reconstruct the palaeo-environment in which the animals lived. C14 dates will be obtained from the wood.