From Surf Wiki (app.surf) — the open knowledge base

Bogoslof Island

Volcanic island in the U.S. state of Alaska

Field	Value
name	Bogoslof Island
photo	BogoslofIsland.jpg
photo_caption	Aerial view, looking south (1994)
map	USA Alaska
map_caption	Alaska
map_width	240
label_position	none
elevation_ft	492
elevation_ref	{{cite web
title	Bogoslof Description and Statistics
work	Alaska Volcano Observatory
publisher	United States Geological Survey
url	http://www.avo.alaska.edu/volcanoes/volcinfo.php?volcname=Bogoslof
access-date	2009-09-01}}
location	Aleutian Islands, Alaska
coordinates
coords_ref
formed_by	Subduction zone volcanism
type	Submarine volcano
volcanic_arc	Aleutian Arc
last_eruption	December 20, 2016–August 30, 2017
embedded	{{designation list	embed = yes
designation1	NNL
designation1_date	1967

| access-date = 2009-09-01}}

Bogoslof Island or Agasagook Island () is the summit of a submarine stratovolcano at the south edge of the Bering Sea, 35 mi northwest of Unalaska Island of the Aleutian Islands chain. It has a land area of 319.3 acre and is uninhabited. It is 1040 m long and 1512 m wide, with a peak elevation of 490 ft. The stratovolcano rises about 6000 ft 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.

History

The first known emergence of the island above sea level was recorded during an underwater eruption in 1796. Since then, parts of the island have been successively added and eroded. About 2000 ft northwest of Bogoslof, a small volcanic dome emerged in 1883 from the same stratovolcano and has become a stack rock formation known as Fire Island. On the southwest side of Bogoslof, another dome erupted in 1796; it is now called Castle Rock. Other eruptions have occurred in 1796–1804, 1806–1823, 1883–1895, 1906, 1907, 1909–1910, 1926–1928, 1992, and 2016–2017. The island is a breeding site for seabirds, seals, and sea lions. An estimated 90,000 tufted puffins, guillemots, red-legged kittiwakes and gulls nest here.

In 1909, President Theodore Roosevelt designated Bogoslof Island and Fire Island a sanctuary for sea lions and nesting marine birds. Together, as the Bogoslof Wilderness, they are currently part of the Aleutian Islands unit of the Alaska Maritime National Wildlife Refuge. In November 1967, Bogoslof Island was designated a National Natural Landmark by the National Park Service. The Bogoslof Island group was added to the National Wilderness Preservation System in 1970.

Eruption year	Lava dome
1796–1804	Castle Rock
1806–1823	none?
1883–1895	Fire Island
1906–1910	none
1926–1928	unnamed
1992	unnamed
2016–2017	none

2016–2017 Eruptions

20 December 2016: A series of short nearly-daily volcanic eruptions started, producing towering volcanic ash clouds and volcanic lightning, changing the geography of the island. As there are no cameras or monitoring stations on the island and the area is usually overcast, details were uncertain. However, when the weather became favorable, it was seen that a small vent slightly offshore of Bogoslof's northeast beach had erupted explosively, fracturing the original island in two, and forming a new, smaller island to the northeast.
25 December 2016: Satellite images of the island showed that the island had fractured into three smaller islands centered on what was thought to be the active vent of the eruption, gaining a net 1.2 acre, compared to its previous area of 71.2 acre. Bogoslof continued to grow in the following weeks, reaching a size of 108.0 acre on January 11, 2017, and merging again into a single island.
02:08 UTC on 20 February (17:08 AKST on 19 February): A significant explosive eruption began at Bogoslof volcano. Seismic and infrasound data showed a series of short-lived explosive pulses through 02:45 UTC; seismicity decreased slightly since then. Recent satellite images show a cloud as high as 25,000 ft asl.
11 March 2017: Bogoslof was 242 acre in size, having more than tripled in size, and forming into a large circular island around the central vent, and would likely continue to grow.
10 May 2017: Bogoslof was estimated to have an area of about 319 acres or 1.3 square kilometers.
17 May 2017: An eruption sent ash 34,000 feet into the atmosphere.
28 May 2017: Another eruption sent ash as high as 35,000 feet and raised Aviation Color Code to red, its highest level. Ash that rises above 20,000 feet is a threat to airliners in the area The National Weather Service Alaska Aviation Weather Unit also issued an alert that the ash cloud may climb as high as 50,000 feet.
30 August 2017: An eruption occurred, with slight volcanic activity continuing into early December, after which the volcano appeared to return to relative inactivity.

Gallery

File:Tufted Puffin Bogoslof Island.jpg|A tufted puffin on Bogoslof Island File:Bogoslof Island fur seal colony.jpg|A fur seal colony on Bogoslof Island File:Bogoslof surface 2009.jpg|Surface of the island in August 2009, showing the 1926–1928 lava dome (left) and 1992 lava dome (right) File:Orca feeding at Bogoslof Island.jpg|Orca feeding on a fur seal at Bogoslof Island File:Bogoslof 2015 map.png|Satellite image of Bogoslof in 2015, before the 2016–2017 eruptions which significantly altered the island's appearance. File:Bogoslof April 20 2018.jpg|Bogoslof Island on April 20, 2018, showing the significant post-eruption terrain change.

References

{{cite gvp
"AVO Bogoslof - Activity Page". Avo.alaska.edu.
Bergsland, K.. (1994). "Aleut Dictionary". Alaska Native Language Center.
Nunn, Patrick D.. (2009). "Vanished Islands and Hidden Continents of the Pacific". University of Hawaii Press.
"Bogoslof Wilderness".
"National Natural Landmarks". U.S. National Park Service.
"Bogoslof Updates". USGS.
(2016-02-09). "USGS: Volcano Hazards Program". Volcanoes.usgs.gov.
"Alaska Volcano Erupts 36 Times in 4 Months, Triples in Size".
Don Crothers. (2017-05-28). "Alaska Volcano Erupts, Flights May Be Disrupted". Inquisitr.com.
(2017-05-28). "Alaska Volcano Erupts Again; Aviation Alert Raised to Red". Bloomberg.

Info: Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

active-volcanoes islands-of-the-aleutian-islands islands-of-aleutians-west-census-area,-alaska national-natural-landmarks-in-alaska submarine-volcanoes volcanoes-of-the-aleutian-islands uninhabited-islands-of-alaska volcanoes-of-unorganized-borough,-alaska stratovolcanoes-of-alaska islands-of-alaska islands-of-unorganized-borough,-alaska quaternary-alaska

Want to explore this topic further?

Ask Mako anything about Bogoslof Island — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report