erta ale – the world’s most inconvenient volcano

11
Erta Ale Ethiopia’s “Smoking Mountain” and “Gateway to Hell”

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Erta Ale – The World’s Most Inconvenient Volcano. Geographic Setting. Latitude: 13°36′N. Longitude: 40°40′E. The Afar Desert region has one of the hottest and driest climates on earth. Tectonic Setting. Erta Ale lies on the Afar Triple Junction , where three plates are diverging: - PowerPoint PPT Presentation

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Page 1: Erta  Ale – The World’s Most  Inconvenient Volcano

Erta Ale Ethiopia’s “Smoking Mountain” and “Gateway to Hell”

Page 2: Erta  Ale – The World’s Most  Inconvenient Volcano

Sarah Shoer and Anahita Valakche

Department of Geology, Colby College

Page 3: Erta  Ale – The World’s Most  Inconvenient Volcano

Geographic Location • 13°36 N 40°40 E′ ′• Northeastern Ethiopia• Afar Triangle

(Depression)• Danakil Desert – “The most cruel

place on Earth” (National Geographic)

Page 4: Erta  Ale – The World’s Most  Inconvenient Volcano

Tectonic Setting

• Afar Triple Junction – Afro-Arabian Rift

System

• Part of East African Rift –Spreading axis

with mantle plume

Page 5: Erta  Ale – The World’s Most  Inconvenient Volcano

Form & Dimensions

• 613 meters tall• Continuously active basaltic shield volcano • Summit caldera (1.6 km x 0.7 km) with two

pit craters–named North and South Crater• Two lava lakes – One of only 6 volcanoes in the world with active

lava lakes • Why are they so rare?

– Both lakes have undergone fluctuation

Page 6: Erta  Ale – The World’s Most  Inconvenient Volcano
Page 7: Erta  Ale – The World’s Most  Inconvenient Volcano

Eruptive History

• 7 (possible) eruptions in last 125 years– 1873, 1903, 1940, 1960, 1967, 2005, & 2007• 2005: 250 livestock killed following a quake that

triggered eruption• 2007: eruption killed 5 people

• Evidence of explosive eruptions (VEI 2) – What are the factors that contribute to limited

data/records?• Hazards: fluid, fast moving lava

Page 8: Erta  Ale – The World’s Most  Inconvenient Volcano

Rocks & Deposits • Basalt and andesitic rocks • Mineralogy: plagioclase and olivine • Deposits:

Fumarolic deposit on North crater

Sulphur stalagtites in fumarole on N rim of

caldera

Pele’s hair near S crater due to frequent lava

fountains

Page 9: Erta  Ale – The World’s Most  Inconvenient Volcano

Other Interesting Information

• 1998-2001: Danakil Desert was off-limits to tourists and foreign researchers!

• Now: tourists can go within 4.3 miles of Erta Ale (despite conditions…)

• 2012: 5 scientists/tourists killed – Afar Revolutionary Democratic

Unity Front responsible (ARDUF)

Page 10: Erta  Ale – The World’s Most  Inconvenient Volcano

Monitoring

Eruptions monitored: – 1.) by their sulfur dioxide plumes– 2.) by the lava lakes via satellite – 3.) or by reports from the (few) locals who live near the

volcano

Page 11: Erta  Ale – The World’s Most  Inconvenient Volcano

Colin's Notes, 2012: The Danakil Depression Part I at http://www.colinsnotes.com/2012/12/07/557/ (accessed January 10, 2015)

Global Volcanism Program, 2013: Erta Ale at http://volcano.si.edu/volcano.cfm?vn= 221080 (accessed on January 10,

2015)

Finlayson, David, 2010: Crustal Architectire of the East African Rift System at http://www.earthscrust.org.au/

science/transects/east-africa_2.html (accessed on January 10, 2015)

Klemetti, Erik, 2010: Volcano Profile: Erta Ale at http://bigthink.com/eruptions/volcano-profile-erta-ale (accessed on

January 10, 2015)

Roscoe, Richard, 2009: Erta Ale Volcano at http://www.photovolcanica.com/VolcanoInfo/Erta%20Ale/Erta %20Ale.html

(accessed January 10, 2015)

Société Volcanologique Européenne, 2005: Erta Ale Volcano, Ethiopia at http://www.sveurop.org/gb/articles/

articles/ErtaAle.htm (accessed January 10, 2015)

Volcanic Hazards Documentation and Logistic Research, 2014: Hot Spot Danakil at http://www.v-e-i.de/vhdl/project/ ertaale.html

(accessed January 10 2015)

Bibliography