Y7 Tectonic Hazards Flashcards
Crust
-50°C to +50°C, made from all kinds of rocks, 5 to 100km thick
Mantle
500°C to 900°C, made from magnesium and iron, 3000km thick
Inner core
5000°C to 6000°C, made from iron and nickel liquid lava, 1260km thick
Outer core
2500°C to 4500°C, made from iron and nickel liquid lava, 2200km thick
Continental crust
25 to 100km thick, made from granite, less dense than oceanic crust
Oceanic crust
5 to 100km thick, made from basalt, denser than continental crust
Convection currents (of hot rock)
rise very slowly, cool then sink again
the movement is so powerful that it moves the crust around
Continental drift
the study of the movement, collision, and division of continents
Fossil correlation
when ancient fossils are distributed in continents that are separated
Eurasian plate
Europe, and most of Asia
Iranian plate
Iran
Arabian plate
Arabia
African plate
Africa
Indo-Australian plate
Australia
North American plate
North America
Caribbean plate
Central America
South American plate
South America
Antarctic plate
Antarctica
Sedimentary rock
rocks made from layers of sediment and dead creatures
Igneous rock
rocks that are made from magma that has cooled and solidified
Metamorphic rock
rocks formed from existing rocks under extreme pressure
Margin
a boundary of a tectonic plate
Constructive plate boundary
the plates move apart causing magma to release
aftereffects: volcano, volcanic island
Destructive-oceanic/continental plate boundary
the oceanic crust moves, the oceanic crust subducts and causes magma to release
aftereffects: earthquake, highlands
Destructive-collision plate boundary
when two continental plates collide
aftereffects: earthquake, volcano
Conservative plate boundary
when two plates slide in the same direction, one moving faster than the other, causing them to snag and build up pressure
aftereffects: crack
