Volcanoes

Volcanoes

Crust
1. Oceanic
  1. Newer
  2. More dense
    1. Sinks
2. Continental
  1. Thicker
  2. Less dense
    1. Floats
  3. Older
Destuctive
1. Continental +Oceanic
  1. Oceanic melted
    1. Excess magma
      1. Volcano
2. Japan
  1. East Coast
3. Ocean trenches
Constructive
1. Mid-Atlantic ridge
Conservative
1. USA
  1. West Coast
2. No volcano
Fold mountains
1. Destructive mountains
  1. Sedimentary rocks fold
    1. And are forced up
  2. South America
    1. Andes
2. Continental
  1. Asia
    1. Himalayas
3. Characteristics
  1. Tall
  2. Snow & glaciers
  3. Lakes in valleys
Types
1. Composite
  1. Japan
    1. Mt. Fuji
  2. Layers of ash and lava
    1. Thick lava
2. Shield
  1. Hawaiian islands
    1. Mauna Loa
  2. Runny lava
3. Supervolcanoes
  1. Formation
    1. Magma basin forms below surface
      1. Causes bulge on surface
        Several km wide
        Cracks & lava vents form
        Lava errupts
        Earthquakes
        Plumes of ash and rock
        Bulge collapses
  2. Effects
    1. Thousands of km^3 of rock, ash & lava
    2. Thick ash cloud = tens of miles destroyed
    3. Ash will block out light over continents
      1. Mini iceages
    4. Ash settle over 100's km^2
      1. Bury fields
      2. Collapse roofs
  3. Characteristics
    1. Flat
    2. Large area
    3. Caldera
Predicting volcanoes
1. Tiltmeters
  1. Measure bulges
2. Seismic activity
3. Volcano history

Resource summary

	Created by mollie.dawson about 10 years ago