Plate Tectonics

• Divergent Plate Boundry (land)

  Plates moving apart and land drops. E.g. East African Rift Valley
• Divergent Plate Boundary (Ocean)

  Mid ocean ridge, Earthquakes are shallow and low magnitude, sediment is thicker as you move away and lithosphere is older E.g. Atlantic Ocean
• Transform Plate Boundary

  No volcanoes, earthquakes are shallow/intermediate depth, high magnitude, long boundary’s are rare - often occur as offsets E.g San Andreas Fault
• Convergent Boundary (Ocean/Continent)

  Plates move towards each other, Ocean lithosphere is subducted underneath the continental lithosphere, Ocean trench - thick layer of sediment on top (cold), fold mountains, earthquakes at all depth and magnitudes, volcanoes
• Benioff Zone

  Line of earthquakes going down the subduction zone,
• Convergent Boundary (Ocean/Ocean)

  Volcano Island Arc, Earthquakes occur at all depths and magnitudes, Ocean trench, volcanoes. The plate that is subducted is older - more cold and dense
• Convergent Boundary (Continent/Continent)

  No volcanoes - magma is sticky and slow, never reaches the top. Earthquakes are shallow but can be any magnitude, fold mountains
• Hot Spots

  There for millions of years. When Below continental it generates lots of lava that builds layers upon layers - Flood basalts, linked to mass extinctions
• Mantle Plume

  Oceanic plate over a hot spot, plume is stationary - tectonic plate moves over. E.g Hawaii