Erta Ale - Colby College

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Ethiopia’s “Smoking Mountain” and “Gateway
to Hell”
Sarah Shoer and Anahita
Valakche
Department of Geology, Colby
College
Geographic Location
• 13°36′N 40°40′E
• Northeastern Ethiopia
• Afar Triangle
(Depression)
• Danakil Desert
– “The most cruel
place on Earth”
(National
Geographic)
Tectonic Setting
• Afar Triple Junction
– Afro-Arabian Rift
System
• Part of East African
Rift
–Spreading axis
with mantle
plume
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
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
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
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)
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
Bibliography
Colin's Notes, I traP noisserpeD likanaD ehT :2012at http://www.colinsnotes.com/ /2012/12/07/557 (accessed January 2015 ,10)
Global Volcanism Program, elA atrE :2013at http://volcano.si.edu/volcano.cfm?vn= no dessecca)221080
January )2015 ,10
Finlayson, David, metsyS ftiR nacirfA tsaE eht fo erticetihcrA latsurC :2010at http://www.earthscrust.org.au/
science/transects/east-africa_ dessecca) lmth.2 on January )2015 ,10
Klemetti, Erik, elA atrE :elfiorP onacloV :2010at http://bigthink.com/eruptions/volcano-profile-erta-ale
(accessed on January
)2015 ,10
Roscoe, Richard, onacloV elA atrE :2009at http://www.photovolcanica.com/VolcanoInfo/Erta%20Ale/Erta
%20Ale.html
)2015 ,10 yraunaJ dessecca)
Société Volcanologique Européenne, aipoihtE ,onacloV elA atrE :2005at http://www.sveurop.org/gb/articles/ articles/ErtaAle.htm
(accessed January )2015 ,10
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
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