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Heimaey of Iceland. An Icelandic tale of fire, flows, and Vestmann ingenuity T. Saylor IV. The Basics. 6 km off the mainland Last erupted January 23, 1973 – Eldfell (Mountain of Fire) Eruption ended late February of the same year
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Heimaey of Iceland An Icelandic tale of fire, flows, and Vestmann ingenuity T. Saylor IV
The Basics • 6 km off the mainland • Last erupted January 23, 1973 – Eldfell (Mountain of Fire) • Eruption ended late February of the same year • Island was originally fueled by Submarine volcanism and created by Helgafell • Fishing City • Population of ~ 4,100 (2011) Fig 1A
Vestmannaeyjar • Along the Mid-Atlantic Ridge • Youngest volcanic system in the Eastern zone of Icelandic volcanism (Subaerial vents of Holocene age) • Named after original Irish slave settlers • Vestmenn (West men), Aeyjar (Islands) • Most Famous Island, Heimaey • Also home to Surtsey (20 km to the SW) Fig 2A Fig 2B
Early History • Iceland first settled by the Norse Gaells (Ostmann, or East men) who brought Irish slaves in 874 (recognized as first settlers) • Hjörleifur, murdered by these slaves in his first year • Ingolfur (3A), Hjörleifur’s blood brother tracked them down to Heimaey, and enacted revenge • Later, in 1627, the islands were captured by Barbary Pirates from Algiers • Gained modern fame through Surtseys eruption in 1963(3B) Fig 3A Fig 3B
IcelandsVolcanic History • ~ 125 volcanic eruptions documented since 874 A.D. (USGS, 1973) • 14 offshore eruptions, centered mainly off of the Reykjanes Ridge (USGS, 1973 Fig 4A
Eldfell • 1:55 AM January 23, 1973, 10 years after Surtsey • A 2 km long fissure opened in the ground in what was originally a peaceful field • A vent centralized to the NE and Eldfell was born Fig 4A Fig 4B
The Fissure/Cone • Dormant for approximately 5,000 years • 20 million cubic meters of tephra ejected • Built the cone in 2 days • Eventually became 183m tall (February of 1973) Fig 7B Fig 7A
Lava! • 230 million cubic meters of lava • Alkali basalt (Murgearite to Hawaiite) • Flow rate of 3-9 meters a day, moving towards the town and harbor, so low effusion rate • Submarine volcanism (Surtseyan), later moved to Hawaaiin • Initial Eruptive rate:100 m3/sec • Seawater to the rescue! Fig 8A
Fig 9A Simmer down now! • Large scale cooling effort • Pumping equipment borrowed from the U.S. • 1.5 billion gallons of water • 30 kmof pipe • 43 pumps • Began in early July, 1973 • Used bulldozers to move tephra over the flows in order to lay pipe Fig 9B
More on cooling • Workers laying pipes over actively moving flows (10A) • No casualties during this effort • A few cases of minor burns • The pipe supports quickly burned, but the pipes themselves were still cool due to the seawater moving through them that they survived. These pipes can still be seen today. • Mostly inhabitants who volunteered to stay and help fight the flames as well as a team of Icelandic scientists and engineers (USGS, 1973) • Most ambitious attempt by man to control a volcanic event Fig 10A
After the Eruption • ~350 buildings burnt to the ground • 70 homes nearly completely buried in tephra • ~ 15 million cubic meters of tephra needed to be removed from the town • Most of the towns original inhabitants returned for the cleanup efforts. Fig 11A
Geothermal power • Heat was extracted from the slowly cooling lava flows; Fig 12A shows latent subthermal heat after the 1973 eruption • Used as a heating system for the town of Vestmannaeyjar • System emplaced in 1979 and operated for ten years until the flows cooled. Fig 12A
Geothermal System Schematic • Fig 13A; a USGS schematic for the geothermal heating system used in Heimaey, Iceland.
Heimaey Today Fig 14B • Approximately 4,100 inhabitants (2011) • Still Icelands most important fishing harbor • For a sweet panorama showing the town today as well as Helgafell and Eldfell, follow this link: http://www.vestmannaeyjar.pano3d.eu/ • Þjóðhátíð, a festival celebrating Icelands independence from Denmark is now the main attraction Heimaey offers; 24 hours of fun and beer! • Also home to Puffins! (Fig 14B) Fig 14A
Heimaey Hazard Map • Lava and pyroclastics Hazard Map • Proximal hazard • Medial Hazard • Distal Hazard • Hazard Maps created by Tom Saylor IV using GoogleEarth, USGS, known weather patterns and other documents for reference Fig 15A
Hazard Map Cont. • Tephra and Ejecta Hazard Map • Proximal hazard • Medial Hazard • Distal Hazard • Hazard Maps created by Tom Saylor IV using GoogleEarth, USGS, known weather patterns and other documents for reference Fig 16A
A note on the previous Hazard Map • During the 1973 eruption, prevailing winds blew tephra to the North East rather than the South West. • The dominant wind pattern for Heimaey is a South Westerly wind, but depending on time of year as well as other weather conditions this can change (Weather Underground, 2012). • Fig 17A (USGS,1973) shows the plume rising from Heimaey during the 1973 eruption. Fig 17A
Volcanic (mostly) Videos • Follow this link for a video of the 1973 eruption and evacuation efforts: http://www.youtube.com/watch?v=VX9e9ei6v3s • Follow this link for an educational video on the 1963 Surtsey eruption and the 1973 eruption of Eldfell:http://www.youtube.com/watch?v=_sRw_e5RA34 • For nearly 30 minutes of uninterrupted Puffin action, follow this link: http://www.youtube.com/watch?v=yVrRJvZdZHg
Image References • 1A : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 2A : Gill, Victoria. "Could Another Icelandic Volcano Erupt Soon?" BBC News. BBC, 05 Oct. 2010. Web. 04 Nov. 2012. <http://news.bbc.co.uk/2/hi/8668604.stm>. • 2B : Google Earth Screen Capture • 3A: ÓVÁ. "IngólfurArnarson." Flickr. Yahoo!, 17 Feb. 2011. Web. 05 Nov. 2012. <http://www.flickr.com/photos/2odinn/5451743423/lightbox/>. • 3B : "Space Aliens Blamed For Electric Universe." Space Aliens Blamed For Electric Universe. N.p., n.d. Web. 04 Nov. 2012. <http://www.thunderbolts.info/tpod/2007/arch07/071105spacealiens.htm>. • 4A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>. • 5A : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 5B : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 6A : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 7A : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 7B : "Iceland in Pictures." Icelandpictures.tumblr.com. N.p., n.d. Web. 04 Nov. 2012. <http://icelandpictures.tumblr.com/post/17314265440/vestmannaeyjar>. • 8A : Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • 9A : http://ffden-2.phys.uaf.edu/212_spring2005.web.dir/philip_fitzgerald/tecniques.htm • 9B : Volcano.und.nodak.edu. N.p., n.d. Web. 4 Nov. 2012. <http://volcano.und.nodak.edu/vwdocs/volc_images/europe_west_asia/heimaey/heimaey.html>. • 10A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>. • 11A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>. • 12A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>. • 13A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>. • 14A : http://drinks.seriouseats.com/images/2011/09/20110901iceland-500.jpg • 14B : Col, Ela. Puffin. 2012. Photograph. Heimaey, Iceland. Flickr, 20 June 2012. Web. 4 Dec. 2012. <http://www.flickr.com/photos/elacol/7427598690/>. • 15A : Courtesy of Tom Saylor IV, 2012. • 16A : Courtesy of Tom Saylor IV, 2012. • 17A : "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. <http://pubs.usgs.gov/gip/heimaey/>.
Text References • Centrum. N.p., n.d. Web. <http://www.centrum.is/~edda/heimaey1.html>. • Einarsson, T., 1974, The Heimaey eruption in words and pictures: Heimskringla, Reykjavik, 56 p. • "Man Against Volcano: Heimaey, Iceland." Man Against Volcano: Heimaey, Iceland. N.p., n.d. Web. 04 Dec. 2012. • Morgan, A. V. "The Eldfell Eruption, Heimaey, Iceland: A 25-year Retrospective." Geoscience Canada 27.1 (2000): 11-18. Web. 13 Nov. 2012. • <http://pubs.usgs.gov/gip/heimaey/>. • Simkin, T., and Siebert, L., 1994, Volcanoes of the World: Geoscience Press, Tucson, Arizona, 349 p. • Williams, R.S., and Moore, J.G., 1983, Man against volcano: The eruption on Heimaey, Vestmannaeyjar, Iceland: U.S. Geological Survey General Interest Publication, 27 p