Список вулканов Аляски, штата США, составлен на основе базы данных программы Global Volcanism Program Смитсоновского института. В штате находятся и материковые вулканы, и островные.
Извержение вулкана Редаут в 1990 году
При высоте в 2857 м вулкан Шишалдина является третьим по величине среди островных вулканов Северной Америки. Кроме того, он является одним из самых активных на Алеутских островах.
Вулкан Шишалдина национальная природная достопримечательност США.
- An image of the volcano at sunset from 2005
- An overhead view of the volcano from November 24, 2013
The first recorded ascent of Shishaldin was in 1932, by G. Peterson and two companions. Given the straightforward nature of the climbing (Alaska Grade 1, snow up to 40 degree slope), it is possible that an earlier ascent occurred, either by native Aleuts, Russians, or other visitors. Shishaldin is a popular ski descent (6,000 ft (1,829 m) vertical) for local climbers (of whom there are few). Due to its remoteness, Shishaldin is not often climbed by outsiders.
The upper 6,600 ft (2,012 m) is almost entirely covered by glacial snow and ice. In all, Shishaldin’s glacial shield covers about 35 square miles (91 km2). It is flanked to the northwest by 24 monogenetic parasitic cones, an area blanketed by massive lava flows. The Shishaldin cone is less than 10,000 years old and is constructed on a glacially eroded remnant of an ancestral somma and shield. Remnants of the older ancestral volcano are exposed on the west and northeast sides at 4,900 to 5,900 ft (1,494 to 1,798 m) elevation. The Shishaldin edifice contains about 300 cubic kilometers (72 cubic miles) of material. A very steady steam plume rises from its small summit crater which is about 500 ft (152 m) across and slightly breached along the north rim.
This volcano has had many recorded eruptions during the 19th and 20th centuries, and a couple of reports of volcanic activity in the area during the 18th century may have referred to Shishaldin as well. Therefore, the volcano’s entire recorded history is spotted with reports of activity. A VO has 24 confirmed eruptions at Shishaldin, making it the volcano with the third most confirmed eruptions (after Akutan and Pavlof). However, Shishaldin has the most eruptions (this means confirmed and possible eruptions) in Alaska, but half of the eruptions are unconfirmed. Recent, well-documented eruptions were in 1995–96 and 1999. Since the 1999 eruption, it has maintained seismic activity, typically having very low-magnitude volcanic earthquakes (most are below magnitude 1) every 1–2 minutes. During this period of non-eruptive seismic activity, it has been puffing steam, with puffs also occurring about every 1–2 minutes. There were reports in 2004 of small quantities of ash being emitted with the steam.
A new period of activity started in July 2019 with incandescence observed in the summit crater during a time of increased seismic activity. On July 23, an active lava lake and minor spattering within the summit crater was observed. A new lava effusion event began on October 13 advancing over the next several weeks. The summit cone partially collapsed on November 25, producing a pyroclastic flow down the northwest side of the volcano and a new lava flow. On December 12, a short-lived explosion from Shishaldin expelled an ash cloud to 20,000–25,000 feet (6,100–7,600 m). During late December, eruptive activity continued with lava flows and low-level explosive activity at the summit. On January 3, 2020, seismicity led to an ash cloud eruption that reached as high as 27,000 feet (8,200 m). Another large ash cloud was emitted on January 19, 2020. The lava flows emitted during the eruptive events have cut deep channels in the snow and ice mantle of the volcano’s north slope. After more than two years of dormancy, on 14 July 2023, the volcano emitted ash plumes up to 40,000 feet high after several explosions at the summit. During the next several days, more ash clouds as well as lava were erupted from the summit crater.
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Список проблемных ссылок
Первое подтверждённое восхождение на вулкан Шишалдина было совершено в 1932 году Дж. Петерсоном и двумя его компаньонами. Учитывая характер восхождения (пологий склон под углом до 40 градусов, покрытый снегом), вполне возможно, что до этого вершину покоряли жители Алеутских островов, русские или кто-либо ещё. Вулкан Шишалдина является популярным у местных жителей склоном для спуска на горных лыжах (вертикальный спуск составляет 1830 м).
Этот вулкан имеет множество зарегистрированных извержений в течение XIX и XX веков, а также несколько сообщений о вулканической деятельности в этом районе в течение XVIII века. Последнее извержение произошло в 2004 году.