Subglacial volcano

A subglacial volcano is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava. Today they are most common in Iceland and Antarctica; older formations of this type are found also in British Columbia and Yukon Territory, Canada.

During the eruption, the heat of the lava from the subglacial volcano melts the overlying ice. The water quickly cools the lava, resulting in pillow lava shapes similar to those of underwater volcanoes. When the pillow lavas break off and roll down the volcano slopes, pillow breccia, tuff breccia, and hyaloclastite form. The melted water may be released from below the ice as happened in Iceland in 1996 when the Grimsvötn caldera erupted, melted 3 cubic km ice and gave rise to a large glacial lake outburst flood.

The shape of subglacial volcanoes tends to be quite characteristic and unusual, with a flattened top and steep sides supported against collapse by the pressure of the surrounding ice and meltwater. If the volcano eventually melts completely through the ice layer, then horizontal lava flows are deposited, and the top of the volcano assumes a nearly-level form. However, if significant amounts of lava are later erupted subaerially, then the volcano may assume a more conventional shape. The more distinctly flat-topped, steep-sided subglacial volcanoes are called tuyas, named after Tuya Butte in northern British Columbia by Canadian geologist Bill Mathews in 1947. In Iceland, such volcanoes are also known as table mountains.

Antarctica eruption

On January, 2008, the British Antarctic Survey (Bas) scientists led by Hugh Corr and David Vaughan, reported (in the journal Nature Geoscience) that 2,200 years ago, a volcano erupted under Antarctica ice sheet (based on airborne survey with radar images). The biggest eruption in the last 10,000 years, the volcanic ash was found deposited on the ice surface under the Hudson Mountains, close to Pine Island Glacier. [ [ BBC NEWS, Ancient Antarctic eruption noted] ]


* [ Volcanoes of Canada: Types of volcanoes] Accessed Jan. 8, 2006

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Volcano — This article is about the geological feature. For other uses, see Volcano (disambiguation) …   Wikipedia

  • Subglacial mound — A subglacial mound (SUGM) is a rounded subglacial volcano. These kinds of volcanoes form when lava erupts beneath a thick glacier or ice sheet.cite web | title = Types of volcanoes | work = Volcanoes of Canada | publisher = Geological Survey of… …   Wikipedia

  • Subglacial eruption — A subglacial eruption is a volcanic eruption that has occurred under ice, or under a glacier. Subglacial eruptions can cause dangerous floods, lahars and create hyaloclastite and pillow lava. Only five of these types of eruptions have been… …   Wikipedia

  • volcano — /vol kay noh/, n., pl. volcanoes, volcanos. 1. a vent in the earth s crust through which lava, steam, ashes, etc., are expelled, either continuously or at irregular intervals. 2. a mountain or hill, usually having a cuplike crater at the summit,… …   Universalium

  • Viedma (volcano) — Infobox Mountain Name= Viedma Photo= Caption= Elevation= Convert|1500|m|ft| 3|abbr=on Location=Argentina Range=Andes Prominence = Coordinates = coord|49.358|S|73.28|W|type:mountain Topographic Type=Subglacial volcano Age= Last eruption=1988 First …   Wikipedia

  • Villarrica (volcano) — View of Villarrica Lake and the eponymous volcano Elevation 2,847 m (9,341 ft) …   Wikipedia

  • Pyramid Mountain (volcano) — Infobox Mountain Name=Pyramid Mountain Photo= Pyramid Mountain.jpg Caption= Pyramid Mountain Elevation=1,103 metres (3,619 feet) Location=British Columbia, Canada Range=Shuswap Highland Prominence =240 m Coordinates =… …   Wikipedia

  • Maitland Volcano — Elevation 2,514 m (8,248 ft) Listing List of volcanoes in Canada …   Wikipedia

  • Cone Glacier Volcano — is a cinder cone in the Boundary Ranges of the Coast Mountains in northwestern British Columbia, Canada. It is part of the Iskut Unuk River Cones group and last erupted during the Holocene period.[1] Cone Glacier contains two arms that surround… …   Wikipedia

  • Mount Cayley volcanic field — Coordinates: 50°07′13″N 123°17′26″W / 50.12028°N 123.29056°W / 50.12028; 123.29056 …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.