Katmai, Alaska (#2)
Katmai National Park, Alaska. View looking up the "Valley of Ten Thousand Smokes" from Overlook Cabin in Katmai National Park. This valley was filled by 10 km3 of pyroclastic flow from the 1912 eruption of Novarupta Volcano, near the head of the valley. When the area was first explored in 1916, thousands of fumaroles were still steaming on top of this pyroclastic flow. The fumaroles have cooled and stopped steaming, but the pryroclastic flow (the pink area) is still largely barren of vegetation. The peaks on the horizon are in part the rim of the caldera of Mount Katmai which formed by collapse as Novarupta ejected 20 km3 of air-fall ash and the pyroclastic flow.
Photo copyright R. W. Decker, 1963.