Oregon, Klamath County, near Cresent
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The pumice deposits you are now standing on are the product of Mt. Mazama, an explosive volcano that collapsed to form the Crater Lake caldera. Mazama stood about 6 miles (9.7 km) south of here (to your left).
About 7,700 years ago Mt. Mazama erupted torrents of seething, red-hot pumice and other volcanic rocks. These glowing avalanches raced down the slopes and flooded the valley that lay here with deposits over 100 feet (30 m) deep.
Even after thousands of years, few trees have become established on the Pumice Desert. There is ample water under the surface, but deficiencies in the soil limit plant growth. Many more years will pass before the surrounding lodgepole pines transform the desert to a forest.
(Inscription within the drawing of Mt.Mazama)
Avalanches of heated rocks ejected by Mt. Mazama flooded downhill. Mostly pumice and scoria, the porous rocks discharged gasses that buoyed up the flow. Some rocks travelled up to 25 miles (40 km) beyond this point.
(Environment • Natural Features) Includes location, directions, 3 photos, GPS coordinates, map.
The pumice deposits you are now standing on are the product of Mt. Mazama, an explosive volcano that collapsed to form the Crater Lake caldera. Mazama stood about 6 miles (9.7 km) south of here (to your left).About 7,700 years ago Mt. Mazama erupted torrents of seething, red-hot pumice and other volcanic rocks. These glowing avalanches raced down the slopes and flooded the valley that lay here with deposits over 100 feet (30 m) deep.
Even after thousands of years, few trees have become established on the Pumice Desert. There is ample water under the surface, but deficiencies in the soil limit plant growth. Many more years will pass before the surrounding lodgepole pines transform the desert to a forest.
(Inscription within the drawing of Mt.Mazama)
Avalanches of heated rocks ejected by Mt. Mazama flooded downhill. Mostly pumice and scoria, the porous rocks discharged gasses that buoyed up the flow. Some rocks travelled up to 25 miles (40 km) beyond this point.
(Environment • Natural Features) Includes location, directions, 3 photos, GPS coordinates, map.