Mount Griggs, formerly known as Knife Peak Volcano, is a

stratovolcano A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with ...

, which lies 10 km behind the volcanic arc defined by other Katmai group volcanoes. Although no historic eruptions have been reported from Mount Griggs, vigorously active

fumarole A fumarole (or fumerole) is a vent in the surface of the Earth or another rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...

s persist in a summit crater and along the upper southwest flank. The fumaroles on the southwest flank are the hottest, and some of the flank fumaroles can roar so loudly that they can be heard from the valley floor. The slopes of Mount Griggs are heavily mantled by fallout from the 1912 eruption of

Novarupta Novarupta is a volcano located on the Alaska Peninsula on a slope of Trident Volcano in Katmai National Park and Preserve, about southwest of Anchorage. Novarupta was formed in 1912, during the largest volcanic eruption of the 20th century, in ...

volcano. The summit consists of three concentric craters, the lowest and largest of which contains a recent summit cone topped by two craters. The volume of the volcanic edifice is estimated at . Isotopic analysis indicates that the source of Griggs' magma is distinct from the other Katmai volcanoes. The mountain was named for Dr. Robert Fiske Griggs (1881–1962), botanist, whose explorations of the area, after the eruption of Mount Katmai in 1912, led to the creation of Katmai National Monument by President

Woodrow Wilson Thomas Woodrow Wilson (December 28, 1856February 3, 1924) was the 28th president of the United States, serving from 1913 to 1921. He was the only History of the Democratic Party (United States), Democrat to serve as president during the Prog ...

in 1918. __NOTOC__

References

External links

Volcanoes of the Alaska Peninsula and Aleutian Islands-Selected Photographs

Mount Griggs
at the Alaska Volcano Observatory
Mount Griggs
at the Smithsonian Global Volcanism Project {{DEFAULTSORT:Griggs, Mount Volcanoes of Lake and Peninsula Borough, Alaska Stratovolcanoes of Alaska Two-thousanders of the United States Katmai National Park and Preserve Aleutian Range Mountains of Lake and Peninsula Borough, Alaska Highest points of United States national parks Pleistocene stratovolcanoes Holocene stratovolcanoes Dormant volcanoes

See also

References

External links