Volcanos Flashcards
what are the landforms volcanos create ?
Ocean Ridges
Rift valleys
Deep see trenches
Island arcs
Young fold mountains
Fault lines
Hot spots
what is an ocean ridge
constrictive boundary
sea floor spreads via magma plumes
magma rises
new crust created
basaltic lave - low viscosity
Mid Atlantic ridge
Rift valley characteristics
constructive boundary
crust moves apart
crust stretches & gets thinner
magma rises, breaks crust & creates new crust
Great African rift valley
deep sea trench
destructive boundary
subduction zone
oceanic crust melts and rises up through the crust
andesitic lava - vicious and explosive
Mariana Trench
Island arc
destructive boundary
subduction zone
oceanic crust melts and rises up through the crust
andesitic lava - vicious and explosive
Young fold mountains
collisional boundary
2 continental crusts meet and push upwards
Himalayas
Fault Lines
conservative boundary
2 plates move parallel and create stress
the surface breaks as a result
san Andreas fault
Hot spots
the core causes magma to become radioactive
magma plumes eat at crust
basaltic lava
breaks through crust
Hawai
How many types of volcanos are there
5
Fissure
Shield
Dome/composit
Ash&cinder
Caldera
Fissure volcano
Constructive
Ridges and valleys
Basaltic lava ejected through fissures
Shield
Constructive
Basaltic lava flows from central vent
Travels before solidifying
Forms layers
Genuinely sloped
Dome/composit
Destructive boundary Andesitic lava from central vent
Solidifies quick
Forms layers
Steep sided
Ash & cinder
Fine ash and cinder ejected from central vent
Builds up & creates layers
Caldera
Gas builds in chamber and explodes
Creates sides collapse
Depression can be filled with water
What are the volcanic hazards
Pyroclastic flow
Nuee ardent
Tephra
Lava flow
Lahar/mudflow
Acid rain
Pyroclastic flow
Hot ash and lava
200m/s
Travel large distances
350-1000°
Pyroclastic flow impacts
Burns
Destroyes everything in its path
Fires
Melt water and cause floods & lahars
Nuer ardent
Cloud of dence material
50km from source
“Glowing cloud”
Tephra
Ejected rock from explosion
Small = far
Big =close
Nuee ardent & tephra impacts
Ash = breathing difficulties, blocks light, change temp
Damage crops
Interup communication
Endanger air travel
Lava flow
Basaltic lava
10km/h
100 + km
Destroy everything in its path
Lava flow impacts
Trigger lahar
Methane build up and cause explosion
Ignites fires
Water evaporate immediately and cause molton showers
Case study
Eyjafjnallajokull Iceland 2010, 3 rating volcanic explosively index
What type of Volcano was is (case study)
Composite volcano on constructive bounty
What caused the eruption
(case study)
Ridge push moved the plates and magma rose and filled the chamber
Primary effect on ppl (case study)
Had to wear face masks to prevent chocking on ash
How many people evacuated
(case study)
700
primary effect on air travel (case study)
ash clouds causes a no fly zone to be established over europe
airlines lost £130 mil a day
primary effect on light
ash cloud blocked sun and turned day to night
what primary effect did the meltwater cause
floods caused due to heat melting the ice pack which lead to roads, buildings and plats to be destroyed
secondary effects of 2010 eyja
sporting events and flights cancelled
water supplies were contaminated
fresh food and raw imports were stopped
kenyas flower industry lost $1.3 mill a day due to lack of flights to europe
what opportuniies did eyjak bring to iceland
no flights ment 2.8 million tonnes of co were not emitted into the atmosphere
iron from the ash entered the north atlantic sea, caused a plankton boom and increased biological processes
promoted tourism and use of other transport services, 1/3 increased eurostar passengers
Lahar
Ash & material mix with water
Highly erosive
60km/h
Engulf everything
Melt ice
Lahar impacts
Melt snow = floods
Silt up river = future floods
Trap ppl
Destroy everything
Acid rain
Carbon dioxide and sulphur dioxide mix with water
Acid rain impacts
Poison water supplies
Death
Dizziness
Make oceans & water acidic = kill wildlife
Crops destroyed
Volcanic hazards
Pyroclastic flow
Nuee ardent
Tephra
Lava flow
Acid rain
