Geo Flashcards
How thick is the crust
30km
How thick is te mantle
2900km
How thick is the core
3 500 km
How many crusts can earth be divided into and name them
2
Oceanic and continental crust
Things you know about the oceanic crust
It is less than 10km thick
It is rich in magnesium and iron
It is made up of ocean flows
It is thinner than the continental crust
Things you know about the continental crust
It is 30km thick
It is rich in silica like granite
Continents or land make up this crust
How does the crust move
The central core of the earth is very hot which causes convection currents in the rock; which move through earth’s mantle and provide the energy that causes plate movement
Name 2 types of plate movement
Convergent and divergent movement
Define divergent movement
Move away from each other
Define convergent movement
Move towards each other
Name 8 of the earth’s plates
African plate
North American plate
South American plate
Eurasian plate
Pacific plate
Nazca plate
Caribbean plate
Define transform movement
Sliding past one another
Why do volcanoes occur
Volcanoes eruption are caused when the mantle is so hot that some rocks melt and become a thick flowing liquid and then eventually the magma pushes out of the vent
What does we call magma that has erupted
Lava
Name the types of volcanoes
Active ,dormant and extinct volcanoes
