Iliamna Volcano, or Mount Iliamna ( Dena'ina: ''Ch’naqał’in'';

Sugpiaq The Alutiiq (pronounced in English; from Promyshlenniki Russian Алеутъ, "Aleut"; plural often "Alutiit"), also called by their ancestral name ( or ; plural often "Sugpiat"), as well as Pacific Eskimo or Pacific Yupik, are a Yupik ...

: ''Puyulek''), is a

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

-covered

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 ...

in the largely volcanic

Aleutian Range The Aleutian Range is a major mountain range located in southwest Alaska. It extends from Chakachamna Lake (80 miles/130 km southwest of Anchorage) to Unimak Island, which is at the tip of the Alaska Peninsula. It includes all of the mountain ...

in southwest Alaska. Located in the Chigmit Mountain subrange in

Lake Clark National Park and Preserve Lake Clark National Park and Preserve is a List of national parks of the United States, United States national park and National preserve, preserve in southwest Alaska, about southwest of Anchorage, Alaska, Anchorage. The park was first proclai ...

, the volcano lies approximately southwest of

Anchorage Anchorage, officially the Municipality of Anchorage, is the most populous city in the U.S. state of Alaska. With a population of 291,247 at the 2020 census, it contains nearly 40 percent of the state's population. The Anchorage metropolita ...

on the west side of lower

Cook Inlet Cook Inlet (; Sugpiaq language, Sugpiaq: ''Cungaaciq'') stretches from the Gulf of Alaska to Anchorage, Alaska, Anchorage in south-central Alaska. Cook Inlet branches into the Knik Arm and Turnagain Arm at its northern end, almost surrounding ...

. It is the 25th most prominent peak in the United States.Alaska Volcano Observatory, Volcano Information - Iliamna
Retrieved Dec. 16, 2022. The volcano's glaciers have extensively altered its profile, cutting, deep and creating steep cliffs and cirques. A ridge extends south from the main body of the mountain, with North Twin and South Twin peaks along its length. There is no summit crater, only a zone of fumaroles just south of the summit at the top of large collapse zone at the head of Red Glacier, which exposes a cross section of the mountain.

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

eruptive activity from Iliamna is little known, but

radiocarbon dating Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for Chronological dating, determining the age of an object containing organic material by using the properties of carbon-14, radiocarbon, a radioactive Isotop ...

seems to indicate at least a few eruptions, all before the

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

an settlement of Alaska. Prehistoric eruptions have been dated to 5050 and 2050 BCE ( VEI-4), 450 BCE and 1650. Historically observed eruptions took place in 1867 (VEI-2) and 1876 (VEI-3), with unconfirmed eruptions in 1933, 1947, 1952 and 1953. Fumaroles located at about elevation on the eastern flank produce nearly constant plumes of steam and minor amounts of

sulfur Sulfur ( American spelling and the preferred IUPAC name) or sulphur ( Commonwealth spelling) is a chemical element; it has symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur atoms ...

ous gases. These plumes are quite vigorous and have resulted in numerous

pilot An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its Aircraft flight control system, directional flight controls. Some other aircrew, aircrew members, such as navigators or flight engineers, are al ...

reports and early historical accounts of "eruptions" at Iliamna Volcano. Earthquake swarms and elevated seismicity and gas emissions were reported in 1996-97 and 2011–13. Iliamna was ranked as a high-threat volcano by the U.S. Geological Survey in 2005 and 2018. The 2018 assessment ranked Iliamna as the 20th most hazardous volcano in the United States, up from 22nd, with an aviation threat score of 34 and an overall score of 115, the second highest of the "high threat" category. Major glaciers radiate from the summit of Iliamna, including Red Glacier, Tuxedni Glacier, Lateral Glacier and Umbrella Glacier. Iliamna was first ascended in 1959. It was designated a

National Natural Landmark The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best e ...

in 1976.

Gallery

Mount Iliamna in July 2015.jpg, Mount Iliamna of the Aleutian Range, July 2015 Iliamna Volcano.jpg, Iliamna Volcano Iliamna Volcano geologic map.png,

Geological map A geological map or geologic map is a special-purpose map made to show various geological features. Rock (geology), Rock units or stratum, geologic strata are shown by color or symbols. Bed (geology), Bedding planes and structural features such ...

References

External links

Iliamna Volcano
at the National Park Service {{DEFAULTSORT:Iliamna, Mount Volcanoes of Kenai Peninsula Borough, Alaska Stratovolcanoes of Alaska Lake Clark National Park and Preserve Aleutian Range Mountains of Alaska Mountains of Kenai Peninsula Borough, Alaska Three-thousanders of the United States National Natural Landmarks in Alaska Holocene stratovolcanoes

Gallery

See also

References

External links