Anne Elliott's photos with the keyword: tuff

Another view from further down the Grand Canyon of the Yellowstone, Yellowstone National Park, Wyoming, US, showing the pink slopes that are seen in some places, dotted with the occasional tree. You can also see a pinnacle above the centre that is red. One of the pinnacles in this canyon had an enormous Osprey nest on the top of it and luckily, when we were there, one of the birds was standing on top of the nest. Taken from Inspiration Point on the North Rim, on 14 September 2012, the 4th day of our week's trip. "The Grand Canyon of the Yellowstone River slices through an ancient hydrothermal basin. The basin developed in rhyolitic lava and ash that flowed into the Yellowstone Caldera about 500,000 years ago. The river carved this spectacular canyon through the hardened lava (rhyolitic rock) and welded ash (tuff). Hot areas and steam vents still exist in the canyon. They allow heat, gases and hot water to escape from the underground Yellowstone Volcano. The canyon is about 20 miles (32 kms) long and parts of the canyon are nearly 1,200 feet (366 m) deep." Taken from a sign at the Canyon. Today in Calgary, it's 1C and has been snowing most of the day.