Transcript Krakatoa eruption of 1883 Megan Hurley, Sarah Noble, Tom Demmer

Krakatoa: 1883
Tom Demmer, Megan Hurley, Sarah Noble
Volcanic Eruptions
• Occur near destructive margins between
tectonic plates
• Eruptions spew lava (called magma while inside) and
ash
• Lava and ash may be deadly to those on slopes and in
valleys surrounding the mountain
Krakatoa
• Volcanic mountain
• Indonesian island of
Rakata
• Elevation: 2,667 feet
• Famous eruption
occurred in 1883
– Eruption began on
June 19, 1883
– Pre- and post-eruption
events went on for
months
• Eruption destroyed
two-thirds of the
island
• Eruption created the
loudest sound ever
observed by mankind
During the Eruption
• Occurred on the morning
of May 20, 1883 in
Indonesia when the ash
started to rise
• For 2 months there were
small eruptions
• August 26-27 was when
the largest explosion in
historical time occurred
• Last day, northern 2/3 of
the island collapsed
During the Eruption
• Largest explosion, heard
as far as Perth in
Australia
• Six cubic miles of rock,
ash, and pumice
• It was so big that debris
scattered as far as
Madagascar
• Ash caused the formation
of other islands
Location and why it happened
• 130 active volcanoes
on Indonesia
• Arc system created
by subduction
• Active volcano in the
Sundra straits
• Krakatoa’s location
makes it highly
explosive
Results of Krakatoa
• Tsunamis:
– Only 1/3 of Krakatoa
remained above sea level
after the eruption
– Wave up to 40 feet tall
– Responsible for about 90%
of casualties
• Deadly Debris:
– Falling tephra and hot
protoclastic flows
– About 2,000 casualties
sufferd severe burns
Results of Krakatoa
• Atmosphere:
– Fine fragments of
tephra pulled into
stratosphere
– Decrease in
temperature and
exotic sky colors
• Anak:
– “Child of Krakatoa”
Results of Krakatoa
• At least 36,417 casualties
• 165 coastal villages destroyed
References
• http://www.geology.sdsu.edu/how_volcanoes_w
ork/Krakatau.html
• http://www.answers.com/topic/krakatoa
• http://www.geology.sdsu.edu/how_volcanoes_w
ork/Thumblinks/Krak_symons_page.html
• http://volcano.und.nodak.edu/vwdocs/volc_imag
es/southeast_asia/indonesia/krakatau_5b.gif
• http://www.geology.sdsu.edu/how_volcanoes_w
ork/subducvolc_page.html
• http://en.wikipedia.org/wiki/Krakatoa