Mount Cleveland (also known as Cleveland Volcano) is a nearly symmetrical
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 ...
on the western end of
Chuginadak Island, which is part of the
Islands of Four Mountains
The Islands of Four Mountains () is an island grouping of the Aleutian Islands in Alaska, United States. The chain includes, from west to east, Amukta Island, Amukta, Chagulak Island, Chagulak, Yunaska Island, Yunaska, Herbert Island, Herbert, C ...
just west of
Umnak Island
Umnak (; ) is one of the Fox Islands of the Aleutian Islands. With of land area, it is the third largest island in the Aleutian archipelago and the 19th largest island in the United States. The island is home to a large volcanic caldera on Moun ...
in the
Fox Islands of the
Aleutian Islands
The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi language, Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before Alaska Purchase, 1867, the Catherine Archipelago—are a chain ...
of
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
. Mount Cleveland is high, and one of the most active of the 75 or more volcanoes in the larger
Aleutian Arc
The Aleutian Arc is a large volcanic arc of islands extending from the Southwest tip of the U.S. state of Alaska to the Kamchatka Peninsula of the Russian Federation.
It consists of a number of active and dormant volcanoes that have formed as a ...
. Aleutian natives named the island after their fire goddess, Chuginadak, who they believed inhabited the volcano. In 1894 a team from the
United States Coast and Geodetic Survey
The United States Coast and Geodetic Survey ( USC&GS; known as the Survey of the Coast from 1807 to 1836, and as the United States Coast Survey from 1836 until 1878) was the first scientific agency of the Federal government of the United State ...
visited the island and gave Mount Cleveland its current name, after then-president
Grover Cleveland
Stephen Grover Cleveland (March 18, 1837June 24, 1908) was the 22nd and 24th president of the United States, serving from 1885 to 1889 and from 1893 to 1897. He was the first U.S. president to serve nonconsecutive terms and the first Hist ...
.
One of the most active volcanoes in the Aleutian Arc, Cleveland has erupted at least 22 times in the last 230 years. A
VEI 3 eruption in 1944 produced the arc's only known volcanic fatality. Most recently Mount Cleveland has erupted three times in 2009, twice in 2010, once in 2011 and in 2016 and 2017.
The volcano's remoteness limits opportunities for its study, and the
Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surv ...
relies heavily on satellites for monitoring. The volcano is primarily hazardous to aircraft; many of the flights over the north Pacific approach the vicinity of the volcano, and
volcanic ash
Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, produced during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used to r ...
released from eruptions can
damage
Damage is any change in a thing, often a physical object, that degrades it away from its initial state. It can broadly be defined as "changes introduced into a system that adversely affect its current or future performance".Farrar, C.R., Sohn, H., ...
sensitive electronic equipment and sensors.
Geological setting
Mount Cleveland is located from the western end of the
Aleutian Arc
The Aleutian Arc is a large volcanic arc of islands extending from the Southwest tip of the U.S. state of Alaska to the Kamchatka Peninsula of the Russian Federation.
It consists of a number of active and dormant volcanoes that have formed as a ...
,
a long volcanic chain extending off the coast of Alaska. Containing over 75 volcanoes, this
volcanic arc
A volcanic arc (also known as a magmatic arc) is a belt of volcanoes formed above a subducting oceanic tectonic plate, with the belt arranged in an arc shape as seen from above. Volcanic arcs typically parallel an oceanic trench, with the arc ...
occurs above the
subduction zone
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second p ...
where the
Pacific Plate plunges under the
North American Plate. As the plate moves deeper into the earth, the increasing pressure results in the loss of
volatiles
Volatility or volatile may refer to:
Chemistry
* Volatility (chemistry), a measuring tendency of a substance or liquid to vaporize easily
** Volatile organic compounds, organic or carbon compounds that can evaporate at normal temperature and pre ...
, certain elements and compounds with low
boiling points
The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.
The boiling point of a liquid varies depending upon the surrounding envi ...
, from various
hydrous
In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...
mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2011): Mi ...
s. One of these compounds is water; its addition to the
mantle wedge
A mantle wedge is a triangular shaped piece of mantle that lies above a subducting tectonic plate and below the overriding plate. This piece of mantle can be identified using seismic velocity imaging as well as earthquake maps. Subducting oceanic ...
formed between the subducting and overriding plates lowers the melting point enough to allow magma to form. The melted material then rises to the surface and forms a volcano—in this case, the Aleutian Arc.
Etymology
The native
Aleut
Aleuts ( ; (west) or (east) ) are the Indigenous people of the Aleutian Islands, which are located between the North Pacific Ocean and the Bering Sea. Both the Aleuts and the islands are politically divided between the US state of Alaska ...
name for Mount Cleveland is ''Chuginadak'' (the name currently given to the island as a whole), referring to the
Aleut
Aleuts ( ; (west) or (east) ) are the Indigenous people of the Aleutian Islands, which are located between the North Pacific Ocean and the Bering Sea. Both the Aleuts and the islands are politically divided between the US state of Alaska ...
fire god
This is a list of deities in fire worship.
African mythology
Bantu mythology
* Nyambe, god of the sun, fire and change
* Nzambia, NZambi, Zambia a Kikongo Mpungu, Nzambi Mpungu, 1st half or other side of God, considered the Chief Creation D ...
dess, thought to reside in the volcano. The volcano's name is a reference to its constant activity, and shows that it was likely highly active even in the distant past.
Aleut oral tradition states that, at one time, the western and eastern halves of Chuginadak were separate islands, and that the isthmus joining them was created by volcanic activity sometime in prehistory.
The "Islands of Four Mountains" name, the geographic group name for Cleveland and its neighbors, was given to the islands by Russian cartographers in the 19th century.
Its current name, Mount Cleveland, was given to it by a
United States Coast and Geodetic Survey
The United States Coast and Geodetic Survey ( USC&GS; known as the Survey of the Coast from 1807 to 1836, and as the United States Coast Survey from 1836 until 1878) was the first scientific agency of the Federal government of the United State ...
expedition in 1894, when it was originally observed by the
USS ''Concord''. Like the other volcanoes in the Four Islands group, which were named after prominent American politicians at the time, Mount Cleveland was named after then-president
Grover Cleveland
Stephen Grover Cleveland (March 18, 1837June 24, 1908) was the 22nd and 24th president of the United States, serving from 1885 to 1889 and from 1893 to 1897. He was the first U.S. president to serve nonconsecutive terms and the first Hist ...
.
Geography and structure
Mount Cleveland is an almost symmetrical
andesite
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...
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
Islands of Four Mountains
The Islands of Four Mountains () is an island grouping of the Aleutian Islands in Alaska, United States. The chain includes, from west to east, Amukta Island, Amukta, Chagulak Island, Chagulak, Yunaska Island, Yunaska, Herbert Island, Herbert, C ...
, a volcanic group in the
Aleutian Arc
The Aleutian Arc is a large volcanic arc of islands extending from the Southwest tip of the U.S. state of Alaska to the Kamchatka Peninsula of the Russian Federation.
It consists of a number of active and dormant volcanoes that have formed as a ...
.
Like all stratovolcanoes, Mount Cleveland grew as
explosive eruption
In volcanology, an explosive eruption is a volcanic eruption of the most violent type. A notable example is the 1980 eruption of Mount St. Helens. Such eruptions result when sufficient gas has dissolved under pressure within a Viscosity, viscous ...
s,
effusive eruption
An effusive eruption is a type of volcanic eruption in which lava steadily flows out of a volcano onto the ground.
Overview
There are two major groupings of eruptions: effusive and explosive. Effusive eruption differs from explosive eruption ...
s, and
lahar
A lahar (, from ) is a violent type of mudflow or debris flow composed of a slurry of Pyroclastic rock, pyroclastic material, rocky debris and water. The material flows down from a volcano, typically along a valley, river valley.
Lahars are o ...
s built it layer by layer into a convex shape. It lies southeast of
Mount Carlisle
Mount Carlisle is a stratovolcano in Alaska which forms part of the 5 mile (8 km) wide Carlisle Island, one of the Islands of Four Mountains which, in turn, form part of the central Aleutian Islands.
Despite its modest summit elevation, a sma ...
and northeast of
Herbert Island
Herbert Island (; ) is an island in the Islands of Four Mountains subgroup of the Aleutian archipelago. It is from Chuginadak Island, separated by the Chuginadak Pass. Yunaska Island is west southwest of Herbert Island.
Measuring across ...
. Mount Cleveland forms the western half of
Chuginadak Island, a broad and uneven bell-shaped landmass, and is the highest of the four volcanic islands.
The island is completely uninhabited; the nearest settlement is
Nikolski on
Umnak Island
Umnak (; ) is one of the Fox Islands of the Aleutian Islands. With of land area, it is the third largest island in the Aleutian archipelago and the 19th largest island in the United States. The island is home to a large volcanic caldera on Moun ...
, about eastward.
Mount Cleveland is wide at its base
and roughly in volume.
The volcano's slope increases markedly with height, from 19° at its lower flanks to 35° near its summit.
Like many other Aleutian volcanoes, Cleveland's flanks are especially rough up to , covered by multiple overlapping lava flows and debris fans that form an apron around the mountain. Lava flows are always built on top of debris flows as a result of the snow melt caused by the emission of heat just before an eruption.
The flows are generally short, under , and thin, less than thick, and are somewhat vegetated.
Although Mount Cleveland is the tallest mountain in the group, it is rarely completely snowed in because of its constant activity disrupts snowfall.
A lack of extant erosion shows that Mount Cleveland is likely a
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 ...
volcano, forming within the last 10,000 years.
All known events have occurred at Mount Cleveland's summit vent,
but there are at least five small
andesite
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...
to
dacite
Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. ...
volcanic domes on the lower flanks.
At times Cleveland has had a summit lava dome. The volcano has no
caldera
A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcanic eruption. An eruption that ejects large volumes of magma over a short period of time can cause significant detriment to the str ...
.
The eastern half of Chuginadak, to which Mount Cleveland is connected by a narrow
isthmus
An isthmus (; : isthmuses or isthmi) is a narrow piece of land connecting two larger areas across an expanse of water by which they are otherwise separated. A tombolo is an isthmus that consists of a spit or bar, and a strait is the sea count ...
, consists of several low-lying
volcanic cone
Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...
s
and two prominent peaks
that have been heavily eroded, partly by glaciers.
Known as the Tana volcanic complex, the two features measure and in elevation. A sample of
rhyolite
Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...
has been recovered from Concord Point,
the easternmost point on the island.
Eruptive history

Eruptions from Mount Cleveland are generally
vulcanian and
strombolian
In volcanology, a Strombolian eruption is a type of volcanic eruption with relatively mild blasts, typically having a Volcanic Explosivity Index of 1 or 2. Strombolian eruptions consist of ejection of incandescent cinders, lapilli, and volcanic b ...
in nature, characterized by short
explosive
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An ex ...
ash clouds sometimes accompanied by
a'a
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or unde ...
flows,
lava fountain
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or unde ...
s,
pyroclastic flow
A pyroclastic flow (also known as a pyroclastic density current or a pyroclastic cloud) is a fast-moving current of hot gas and volcanic matter (collectively known as tephra) that flows along the ground away from a volcano at average speeds of b ...
s,
ash and
steam
Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is inv ...
emissions,
lava dome
In volcanology, a lava dome is a circular, mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions ...
growth,
and the ejection of
breadcrust bombs.
Hot springs were reportedly found on the volcano in the 1800s,
and persistent
fumarolic activity was observed in the 1980s and 1990s.
Mount Cleveland is a site of persistent steam emissions and thermal anomalies that represent constant background activity.
During 2011, a summit lava dome formed, by continuous intrusion of magma at the summit. Late in 2011, nearly 6 explosions demolished the dome. In June 2012, another small dome was observed.
Little is known about Cleveland's early eruptive history as its remoteness makes it a difficult area to investigate, and discrepancies in names have caused confusion between events there and those on nearby
Carlisle
Carlisle ( , ; from ) is a city in the Cumberland district of Cumbria, England.
Carlisle's early history is marked by the establishment of a settlement called Luguvalium to serve forts along Hadrian's Wall in Roman Britain. Due to its pro ...
. Even today, not all possible events are confirmed as eruptions by the
Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surv ...
, and many are listed as "possible." In observed history, Mount Cleveland may have first erupted in 1744; the first confirmed eruption occurred in 1828. The volcano erupted again in 1836 (possibly), 1893, 1897 (possibly), 1929 (possibly), 1932, and 1938 (possibly).
The first notable eruption from Mount Cleveland was a
Volcanic Explosivity Index
The volcanic explosivity index (VEI) is a scale used to measure the size of explosive volcanic eruptions. It was devised by Christopher G. Newhall of the United States Geological Survey and Stephen Self in 1982.
Volume of products, eruption c ...
(VEI) 3
Vulcanian eruption
A Vulcanian eruption is a type of volcanic eruption characterized by a dense cloud of ash-laden gas exploding from the crater and rising high above the peak. They usually commence with phreatomagmatic eruptions which can be extremely noisy due t ...
that occurred between June 10 and June 13, 1944.
Lava flow
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...
s extended from the summit, and an ash plume high was produced. Large boulders were reportedly ejected and carried out to sea by eruptive force. The eruption had the distinction of being the only confirmed direct volcanic fatality in Alaska; a small detachment from the
Eleventh Air Force
The Eleventh Air Force (11 AF) is a Numbered Air Force of the United States Air Force Pacific Air Forces (PACAF). It is headquartered at Joint Base Elmendorf–Richardson, Alaska.This unit is not related to the Eleventh Air Force headquart ...
was stationed on the volcano at the time, and one Sergeant Fred W. Purchase left his post early in the eruption to take a walk and never returned, probably killed by
mudslide
A mudflow, also known as mudslide or mud flow, is a form of mass wasting involving fast-moving flow of debris and dirt that has become liquified by the addition of water. Such flows can move at speeds ranging from 3 meters/minute to 5 meters/ ...
s. At approximately 10:20, a boat sent to search for Purchase witnessed the end of the eruption. The island was abandoned for the remainder of the war.
Mount Cleveland erupted more recently in 1951, 1953, 1954 (possibly), 1975 (possibly), 1984 through 1987, 1989, 1994, and 1997. The volcano has received more focused attention in recent times due to its increased activity: it erupted in 2001, 2005, three times in 2006, 2007, three times in 2009, and twice in 2010. Of these, the most significant eruption was the 2001 eruption, which produced a high ash plume. This plume dispersed across Alaska, an unusual distance that allowed detailed satellite observations to be made.
Nikolski and the surrounding region was the site of several hours of ashfall, represented in satellite imagery as areas of discolored snow.
This eruption significantly disrupted air traffic in the area.
On June 19, 2012, a pilot reported an ash-producing explosion on Mount Cleveland. Due to continuing seismic activity, the volcano was placed on the USGS Volcano Watch List in the orange or "watch" category the following day. AVO continues to keep Cleveland on the watch because of a persistent anomaly at the summit. AVO suspects it could be dome growth. Other minor ash producing explosions occurred on June 26, July 12, and August 19.
On May 4, 2013, the volcano began a low-level eruption, with a plume of ash observed at .
The volcano erupted several times in 2014 and 2015, and a single explosion was detected by the AVO on April 16, 2016.
In total the volcano has erupted at least 22 times in the last 230 years.
Monitoring

Today, the
Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surv ...
monitors activity at Mount Cleveland using satellite imagery. Cloud cover often obscures the volcano, which makes many events difficult to follow.
In addition, the low resolution of the satellite imagery allows minor events, which do not make an impression on the satellite picture, to pass unnoticed.
There are no seismic or geophysical instruments on the mountain
(the nearest are in Nikolski), and some eruptions are first observed by pilots flying over the volcano.
A field study was conducted in late 2001,
and an automatic system based on thermal anomalies was implemented following eruptive events in 2005.
In recent years the Alaska Volcano Observatory has made an effort to expand volcanic coverage westward along the Aleutian Arc.
The biggest threat posed by an eruption from Mount Cleveland is its
ash plume, which can damage sensitive electronic equipment on overflying planes. Many aircraft traveling over the North Pacific and over the Arctic come within the vicinity of such a plume; the only way to avoid damage is to reroute the flight, which delays arrival time and adds $5,500 to $6,000 in extra fuel costs.
Cleveland has therefore been assessed by the
United States Geological Survey
The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...
as "a volcano with a high aviation threat score and no real-time ground based monitoring at the present time".
See also
*
List of mountain peaks of Alaska
This article comprises three sortable tables of major mountain peaks of the U.S. State of Alaska.
The summit of a mountain or hill may be measured in three principal ways:
#The topographic elevation of a summit measures the height of the summi ...
*
List of volcanoes in the United States
This article contains a list of volcanoes in the United States and its territories.
Alaska
American Samoa
Arizona
California
Colorado
Hawaii
Idaho
Illinois
Louisiana
Michigan
Mississippi
Missouri
Nevada
Ne ...
References
External links
Cleveland eruption updates Alaska Volcano Observatory
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey (USGS), the Geophysical Institute of the University of Alaska Fairbanks (UAFGI), and the State of Alaska Division of Geological and Geophysical Surv ...
.
{{DEFAULTSORT:Cleveland, Mount
Active volcanoes
Stratovolcanoes of Alaska
Volcanoes of the Aleutian Islands
Landforms of Aleutians West Census Area, Alaska
Islands of Four Mountains
21st-century volcanic events
Volcanoes of Unorganized Borough, Alaska
Holocene stratovolcanoes
Grover Cleveland