| Stepovak Bay | |
|---|---|
  Stepovak Bay | |
| Coordinates | 55°43′N159°50′W / 55.717°N 159.833°W Coordinates: 55°43′N159°50′W / 55.717°N 159.833°W |
| Ocean/sea sources | Pacific Ocean |
| Basin countries | U.S. |
Stepovak Bay is a bay located on the Alaska Peninsula, Alaska, on the Gulf of Alaska. It was named Stepovakho Bay or Stepof's Bay by the United States Coast and Geodetic Survey in 1888 for Stepanof, a Russian captain. [1]
Stepovak Bay is framed by the Stepovak Bay group of volcanoes, a chain of 5 cinder cone volcanoes in the Aleutian Arc. The volcanoes include Mount Kupreanof [2] and four numbered volcanoes (Stepovak Bay 1, 2, 3, & 4). Mount Kupreanof and Stepovak Bay 2 and 4 erupted within the last 10,000 years, while Stepovak Bay 1 and 3 erupted before this, sometime in the Late Pleistocene. [3] Mount Kupreanof's most recent eruption was possibly in March 1987. [2]
Mount Katmai is a large stratovolcano on the Alaska Peninsula in southern Alaska, located within Katmai National Park and Preserve. It is about 6.3 miles (10 km) in diameter with a central lake-filled caldera about two by three miles in size, formed during the Novarupta eruption of 1912. The caldera rim reaches a maximum elevation of 6,716 feet (2,047 m). In 1975 the surface of the crater lake was at an elevation of about 4,220 feet (1,286 m), and the estimated elevation of the caldera floor is about 3,400 ft (1,040 m). The mountain is located in Kodiak Island Borough, very close to its border with Lake and Peninsula Borough.
Mount Spurr (Dena'ina: K'idazq'eni) is a stratovolcano in the Aleutian Arc of Alaska, named after United States Geological Survey geologist and explorer Josiah Edward Spurr, who led an expedition to the area in 1898. The Alaska Volcano Observatory (AVO) currently rates Mount Spurr as Level of Concern Color Code Green. The mountain is known aboriginally by the Dena'ina Athabascan name K'idazq'eni, literally 'that which is burning inside'.
Redoubt Volcano, or Mount Redoubt, is an active stratovolcano in the largely volcanic Aleutian Range of the U.S. state of Alaska. Located at the head of the Chigmit Mountains subrange in Lake Clark National Park and Preserve, the mountain is just west of Cook Inlet, in the Kenai Peninsula Borough about 110 miles (180 km) southwest of Anchorage. At 10,197 feet (3,108 m), in just over 5 miles (8 km) Mount Redoubt attains 9,150 feet (2,700 m) of prominence over its surrounding terrain. It is the highest summit in the Aleutian Range. In 1976, Redoubt Volcano was designated as a National Natural Landmark by the National Park Service.
Mount Veniaminof is an active stratovolcano on the Alaska Peninsula. The mountain was named after Ioann Veniaminov (1797–1879), a Russian Orthodox missionary priest whose writings on the Aleut language and ethnology are still standard references. He is a saint of the Orthodox Church, known as Saint Innocent for the monastic name he used in later life.
Pavlof Volcano is a stratovolcano of the Aleutian Range on the Alaska Peninsula. It has been one of the most active volcanoes in the United States since 1980, with eruptions recorded in 1980, 1981, 1983, 1986–1988, 1996–1997, 2007, 2013, twice in 2014, 2016, and is currently erupting as of August 2021. Basaltic andesite with SiO2 around 53% is the most common lava type. The volcano is monitored by the Alaska Volcano Observatory- 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 Surveys (ADGGS). With a threat score of 95, the threat from future eruptions is considered to be high; much of this threat comes from the possibility of disruption of nearby air routes by large releases of ash. The mountain currently has basic real-time monitoring, but the USGS would like to improve instrumentation at the site. The mountain shares a name with the nearby Pavlof Sister, which last erupted in 1786.
Mount Akutan, officially Akutan Peak, is a stratovolcano in the Aleutian Islands of Alaska. Akutan Peak, at 4,275 feet (1,303 m), is the highest point on the caldera of the Akutan stratovolcano. Akutan contains a 2 km-wide caldera formed during a major explosive eruption about 1600 years ago. Recent eruptive activity has originated from a large cinder cone on the NE part of the caldera. It has been the source of frequent explosive eruptions with occasional lava effusion that blankets the caldera floor. A lava flow in 1978 traveled through a narrow breach in the north caldera rim to within 2 km of the coast. A small lake occupies part of the caldera floor. Two volcanic centers are located on the NW flank: Lava Peak is of Pleistocene age; and, a cinder cone lower on the flank which produced a lava flow in 1852 that extended the shoreline of the island and forms Lava Point. An older, mostly buried caldera seems to have formed in Pleistocene or Holocene time, while the current caldera formed in a VEI-5 eruption c. 340 AD. AVO has recorded 33 confirmed eruptions at Akutan, making it the volcano with the most eruptions in Alaska.
Bogoslof Island or Agasagook Island is the summit of a submarine stratovolcano at the south edge of the Bering Sea, 35 miles (56 km) northwest of Unalaska Island of the Aleutian Island chain. It has a land area of 319.3 acres (1.292 km2) and is uninhabited. The peak elevation of the island is 490 feet (150 m). It is 1,040 meters (3,410 ft) long and 1,512 m (4,961 ft) wide. The stratovolcano rises about 6,000 ft (1,800 m) from the seabed, but the summit is the only part that projects above sea level. The island is believed to be relatively new, with the volcano being entirely below sea level before 1796, and most of the presently 300 acre island being formed by eruptions since 1900.
Mount Okmok is the highest point on the rim of Okmok Caldera on the northeastern part of Umnak Island in the eastern Aleutian Islands of Alaska. This 9.3 kilometers (5.8 mi) wide circular caldera truncates the top of a large shield volcano. The volcano is currently rated by the Alaska Volcano Observatory as Aviation Alert Level Green and Volcanic-alert Level Normal.
Mount Cleveland is a nearly symmetrical stratovolcano on the western end of Chuginadak Island, which is part of the Islands of Four Mountains just west of Umnak Island in the Fox Islands of the Aleutian Islands of Alaska. Mt. Cleveland is 5,675 ft (1,730 m) high, and one of the most active of the 75 or more volcanoes in the larger Aleutian Arc. Aleutian natives named the island after their fire goddess, Chuginadak, who they believed inhabited the volcano. In 1894 a team from the U.S. Coast and Geodetic Survey visited the island and gave Mount Cleveland its current name, after then-president Grover Cleveland.
Frosty Peak Volcano, also known as Mt. Frosty, Frosty Volcano, or Cold Bay Volcano, is a 6,299 ft (1,920 m) stratovolcano at the southwest end of the Alaska Peninsula in the U.S. state of Alaska.
Mount Adagdak is a Pleistocene age stratovolcano on the northernmost extremity of Adak Island in the Aleutian Islands, Alaska. Located about 1,180 miles (1,900 km) from Anchorage, the mountain is located about 1.4 kilometers (0.9 mi) south of Cape Adagdak, for which it was named in 1948 by the United States Geological Survey.
Mount Edgecumbe, until May 2022 considered to be a "dormant volcano" but since reclassified by the Alaska Volcano Observatory (AVO) as "historically active", is located at the southern end of Kruzof Island, Alaska, about 15 miles (24 km) west of Sitka. The volcano is about 9.9 miles (16 km) east of the Queen Charlotte Fault that separates the North American and Pacific Plates, and is the highest point in the Mount Edgecumbe volcanic field, an area of about 100 square miles (260 km2) on Kruzof Island that also includes Crater Ridge and Shell Mountain.
Tanaga is a 5,924-foot (1,806 m) stratovolcano in the Aleutian Range of the U.S. state of Alaska. There have been three known eruptions since 1763. The most recent was in 1914 and produced lava flows. It sits west of another stratovolcano known as Mount Takawangha, which last erupted in 1550.
The Alaska Volcano Observatory (AVO) is a joint program of the United States Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the State of Alaska Division of Geological and Geophysical Surveys (ADGGS). AVO was formed in 1988, and uses federal, state, and university resources to monitor and study Alaska's volcanology, hazardous volcanoes, to predict and record eruptive activity, and to mitigate volcanic hazards to life and property. The Observatory website allows users to monitor active volcanoes, with seismographs and webcameras that update regularly. AVO now monitors more than 20 volcanoes in Cook Inlet, which is close to Alaskan population centers, and the Aleutian Arc due to the hazard that plumes of ash pose to aviation.
Prindle Volcano is an isolated basaltic cinder cone located in eastern Alaska, United States, in the headwaters of the East Fork of the Fortymile River. The cone is fresh-looking and has a base approximately 900 metres wide. It is the northwesternmost expression of the Northern Cordilleran Volcanic Province. The cinder cone, and an approximately 11-kilometre (6.8-mile) long lava flow which breached the margin of the cone, erupted in the Pleistocene approximately 176,000 years ago. Rocks forming the Prindle Volcano occur within, and penetrated through, the Yukon–Tanana upland which is a large region of mostly Paleozoic-Mesozoic metamorphosed and deformed sedimentary, volcanic, and intrusive rocks that are intruded by younger Cretaceous and Cenozoic granitic rocks. Xenoliths in the volcano's ejecta provide a sample of lower crust material.
Mount Kupreanof is a stratovolcano on the Alaska Peninsula, United States. It is the largest and the northeasternmost in a group of five volcanoes opposite from Stepovak Bay. Mount Kupreanof displays extremely strong fumarole activity and its latest eruption in 1987 produced minor steam and ash emission. This is the only known historical eruption from Mount Kupreanof.
Alaska's Mount Redoubt volcano began erupting on March 22, 2009, and activity continued for several months.
The Aleutian Arc is a large volcanic arc in the U.S. state of Alaska. It consists of a number of active and dormant volcanoes that have formed as a result of subduction along the Aleutian Trench. Although taking its name from the Aleutian Islands, this term is a geologic grouping rather than a geographic one, and the Aleutian Arc extends through the Alaska Peninsula following the Aleutian Range to the Aleutian Islands.
Mount Takawangha is a stratovolcano located in Tanaga Island, Alaska. It sits in close proximity with another volcano known as Mount Tanaga, which shares the same name as the island itself. Older and more eroded volcanoes can also be found east of Takawangha. Its elevation is 4,754 ft, making it the second-highest peak on the island.
 | This article about a location in the Aleutians East Borough, Alaska is a stub. You can help Wikipedia by expanding it. |