Volcanic ash and Vog Flashcards
What is volcanic ash
Finely ground volcanic rock, glass
What is the most widespread volcanic hazard
Volcanic ash
What happens to ash in jet engines
Melts and coats the turbine blades, which may shut down engines.
What is a signal that a dormant volcano is reawakening
Earthquakes
What happened to KLM flight in 1989
FLew through ash cloud in Mt. redoubt. all 4 engines stalled , but managed to restart and land safely at anchorage.
Plate tectonic setting of Aleutian islands, in Alaska
Subduction zone, gives you a chain of volcanos
what happens when plates don’t subduct?
Then 2 plates collide and form mountain range like himalayas
how thick are tectonic plates
100km thick
explain the aleutian subduction plate formation
- South plate went below north
- going down releases water which promotes melting of magma, which leads to magma release
- trapped magma makes it explosive
- increased stress causes more earthquakes
what can you find in active subduction zones
earthquakes and volcanoes
What’s another word for tectonic plate
Lithosphere
what are the volcano alert colours
Green, yellow, orange, red
health risks of people at anchorage against ash
- damage lungs
- with rainfall can clog sewages
- structural damage on building due to heavy weight
- slippery: tamper road conditions
- can cause skin injury because it’s sharp
eyjafjallajokull volcano, where is it?
Iceland
Diameter of Katla’s caldera
10km
when did katla last erupt? how much bigger was it compared to Eyjafjallajokull?
1918, 3 times bigger. has potential for much larger eruptions.
Potential sign of pressure building in Katla’s magma chamber? how is it being monitored?
Building of caldera, uplift of surface. Monitored by GPS.
different between Eyjafjallajokull and Katla’s volcanic plumbing system?
Eyjafjallajokull has magma intrusion through sills
Katla has magma chamber
Plate tectonic setting of iceland
- on mantle plume
- on the mid-atlantic ridge
- not a subduction zone or a chain would be seen
Health hazard without eruption
Vog
Where are Vogs seen
Hawaii
What winds in Hawaii Vog
- north-easterly trade winds
- southern kona winds
- emission source from white plume
what is vog composed of
SO2 and aerosols
- aerosols created when SO2 combines with other volcanic gases, interacts with O2, moisture , dust and sunlight for minutes to days
What is particulate matter of Vog
PM2.5, respirable particles
how can vog grow
by abosrbing water vapour and other gases to move up human tracts
symptoms of vog
cough, irritation everywhere, chest tightness
