Tectonic plates

?
  • Created by: cowsgomoo
  • Created on: 08-03-18 19:04

What can we do?

Prediction - Uses historical evidence and monitoring. Predict the general locations where natural disasters are most likely to happen.

Protection - Designing buildings and strengthening roads/ bridges to withstand natural disasters.

Planning - Planning and preparing what to do during and after natural disasters.

Monitoring - Using scientific equipment to detect warning signs. Gives information about the movement of plates and the consequences that might have. Difficult to predict exact date and time.

1 of 4

Constructive plate margin

Examples : Iceland, Hawaii, African plate and South American plate

  • The upper part of the mantle melts and the hot magma melts (convection)
  • Tectonic plates are moved away from each other due to gravity (slab pull, ridge push)
  • Molten magma rises between the gap and cools down to form solid rock (lava)
  • The new part of the plate sometimes fractures as it moves causing shallow and small earthquakes
  • In a few places magma erupts into a volcano
  • The lava is runny and spreads out before solidifying, creating a wide base and a gently sloping shield volcano
  • Two oceanic plates
2 of 4

Destructive plate margin

Examples: Pacific and Eurasian plate

  • The oceanic plate meets the continental plate
  • The oceanic plate (the denser of the two) is subducted (pulled down) by gravity into the mantle beneath the lighter and thicker continental plate
  • There is friction between the two plates and as they rub past each other, they fracture which causes earthquakes to happen
  • As the oceanic plate sinks deeper into the mantle, it causes part of the mantle to melt
  • Hot magma rises up through the crust and becomes increasingly viscous 
  • It produces composite volcanoes which are steep sided with violent eruptions
3 of 4

Conservative plate margin

Example: San Andreas fault in California (where the North American and Juan de Fuca plates meet)

  • Two plates move parallel to each other
  • Can move in the same direction but at different speeds or in opposite directions
  • As the plates move past each other, friction causes them to get stuck
  • Pressure builds up until the rock fractures and earthquakes are caused
  • There are no volcanoes as there is no gap for magma to rise through
4 of 4

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Natural hazards resources »