Tectonic Hazards

• Earthquake


  A sudden or violent movement within the Earth's crust followed by a series of shocks
• Plate margins


  The border between 2 tectonic plates
• Tectonic plates


  Earth's crust is split into a number of plates about 100km thick
• Oceanic crust


  A thin, dense crust which underlies the ocean basins
• Continental crust


  A less dense, thick crust that underlies land
• Convection currents


  Movement of molten rock in the mantle underneath the Earth's surface
• Constructive plate margin


  Plates move apart and new crust is formed as magma rises towards the surface
• Destructive plate margin


  Plates move towards each other and the oceanic plate may subduct under the continental plate
• Collision plate margin


  Two continental plates collide. Neither plate is forced under the other, and so both are forced up and form fold mountains
• Conservative plate margin


  Occurs when plates move apart. Volcanoes are formed as magma wells up to fill the gap, and eventually new crust is formed
• Volcano


  A large and often conical-shaped landform formed over a long time by a series of eruptions
• Hot spots


  Volcanoes form here where the crust is thin and magma is able to break through to the surface
• San Andreas fault


  Example of a conservative plate margin - no volcanoes as there is no magma
• Nazca plate and the South American plate


  Example of a destructive plate margin - formed the Andes (fold mountains)
• The North American plate and the Mid-Atlantic Ridge


  An example of a constructive margin - formed the Icelandic volcano Eyjafjallajökull
• Geothermal energy


  Hot water from within the crust provides heat and hot water for 90% of all buildings in Iceland
• Tourism


  Dramatic landscapes draw in people and provides jobs for locals
• Monitoring


  Using scientific equipment to detect warning signs of tectonic hazards
• Prediction


  Using historical evidence and monitoring to make predictions about when and where a tectonic hazard may happen
• Protection


  Designing buildings that will withstand tectonic hazards
• Planning


  Identifying and avoiding places most at risk