Tectonic hazards

• What are the parts of the Earth?

  • inner core
  • outer core
  • mantle
  • crust
• What is the core?

  a ball of solid (inner) and liquid (outer) iron and nickel
• What is the mantle?

  the layer that surrounds the core, which is semi-molten rock
• What is the crust?

  the outermost layer of the Earth which is very thin (5-100km thick)
• What is the crust divided into?

  slabs called tectonic plates which float on the mantle
• What are the two tectonic plates found in the crust?

  • continental crust- thicker (30-50km) and less dense
  • oceanic crust- thinner (5-10km) and more dense
• How can tectonic plates move?

  because the rock in the mantle is only semi-solid and molten
• What is a plate margin/boundary?

  the place where tectonic plates meet
• What are the different types of plate margins?

  • destructive
  • constructive
  • conservative
• What is a destructive margin?

  where 2 plates are moving towards eachother
• What happens when an oceanic and continental plate meet?

  the denser oceanic plate is forced down into the mantle and destroyed, creating volcanoes and ocean trenches
• What happens when 2 continental plates meet?

  the plates collide and the ground is folded and forced upwards to create mountain ranges
• What is a constructive plate margin?

  where 2 plates are moving away from eachother
• What happens at the constructive margin?

  magma (molten rock) rises from the mantle to fill the gap and cools, creating new crust
• What is a conservative margin?

  where 2 plates are moving sideways past each other or are moving in the same direction but at different speeds