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• Nevado Del Ruiz, Colombia
• Volcan Del Fuego,Colima,Mexico
• Nyiragongo, Zaire/Congo, Africa
Nevado Del Ruiz, Colombia http://www.youtube.com/watch?v=5cjTTu5A9iw
Overview:
• Location
• Type of volcano
• Times of eruption
• Magma type
• Casualties
Location:
• In the Andes mountains of South America.– In West-central
Colombia.
Type of volcano:
• Stratovolcano, also called composite volcano.
• With an elevation of 5,389 m.
Times of eruption:
• Nevado Del Ruiz generated killer mudflows in 1595.
• Then again in 1845, hundreds died in settlements located at the site of Armero.
– After the 1845 eruption Nevado Del Ruiz was quiet for 140 years.
– People forget about the destruction and Armero was built on the same site, growing to a town of 30,000 by 1980
Cont.
• Until the 1985 eruption that produced mudflows which reached the town of Armero.
Magma type:
• High viscosity andesitic to rhyolitic lava flows.– Explosive eruption style.– Eruption types: Plinian
Casualties:• More than 23,000 people were killed.
• 5,000 injured.
• 5,00 homes were destroy.
Volcan Del Fuego Colimahttp://www.youtube.com/watch?v=-3EQiWnou4w
Overview:
• Location
• Type of volcano
• Times of eruption
• Magma type
• Casualties
Location
Type of volcano
• Composite or Stratovolcano
• Considered Mexico’s most dangerous and active volcano
• Erupted a few dozen times since the 1500’s
Location
• 280 miles west of Mexico
• Subduction zone between the Pacific plate and the North American plate
• 13,325 ft. high
• Pacific ‘Ring of fire’
Oceanic-Continental Subduction Zone
Ring of Fire
Magma type
• High viscosity andesitic to rhyolitic lava flows– Explosive eruptive style(pyroclastic lava flow)
Nyiragongo, Congo
One of eight volcanoes in the Virunga National Park.
http://www.youtube.com/watch?v=W_meqhjQxb8http://www.youtube.com/watch?v=jBro5jOG00s
Overview:
• Location
• Type of volcano
• Times of eruption
• Magma type
• Casualties
East African Rift Zone
Nyiragongo, Strato or Shield??
•
Recent Eruption Disaster• Erupted 1/17/02, at 8:35am
• Earthquakes were felt for 2 weeks preceding the eruption, every 40 seconds during the eruption, and have died down exponentially, yet continue still
• Spewed 250 Million cubic meters of lava (125,000 Olympic-sized swimming pools)
• As stratovolcano, no pyroclastic flows, and the lava flowed at a slow rate of 1.2 - 1.6 km/hour
• Eruptions have occurred every 10 years since 1884
Cones and Craters Surround the Volcano.
• Nyiragongo erupts January 17, 2002
• Lava flows from the southern flanks toward Goma.
• Basaltic flows reach 1.2 to 1.8 km/hour.
Basaltic Trail Blazer.
Nyiragongo’ Refugees.
• Approximately 400,000 evacuated for 3 days.
• 12000 families left homeless
80 Percent of Goma Destroyed.
• 14 villages damaged.
• 45 dead from eruption.
• Civil Disobedience results in more.
Crater in Nyiragongo’s Summit. Is it half full or half empty?
Oct, 7, 1999
Quito, Ecuador
Volcanoes rolling ash and rings of steam rise from 15,728 foot-tall Guagua Pichincha on the morning of October 7, 1999.No sound or tremor alerted the nearby city of Quito and wind swept ash away quickly.
Quito, EcuadorOct, 7, 1999
Shower of ash turning day to night for the first time since 1960
Fig. 6-29, p.141
Predicting Eruptions• Establish a volcano’s
history– Active– Dormant
• Monitor changes and anomalies– Earthquakes– Changes in shape or
elevation– Volcanic gases– Changes in ground
temperature– Composition of water
Predicting Eruptions