The Terraces at Mammoth.

In Explore August 19, 2011, #448.

At the north end of Yellowstone National Park is the area known as Mammoth Hot Springs. The famous terraces are there and when we visited a few weeks ago were becoming active once again after showing very little activity for decades. We had been there in the late seventies when they were active but found them gray and inactive in the mid-eighties and again in 2008. This photo was taken at the top of the terraces looking north. In this picture the mistiness around the tree is steam rising from the hot water which, seeping up through the ground, forms these terraces from calcium carbonate dissolved in the water.