Knowledge organisers B1-15 Flashcards
What is the core?
The centre of the earth that is made up of dense rocks containing iron and nickel and divided into a solid inner core and molten outer core.
What is the mantle?
Layer beneath the core made up of molten and semi-molten rocks containing lighter elements such as silicon and oxygen.
What is the continental crust?
Older, thicker layer of crust, which makes up the Earth’s landmasses.
it is less dense than oceanic crust.
What is the lithosphere?
The layer of the earth which consists of the upper mantle and crust
What is the asthenosphere?
Lies beneath the lithosphere and is semi molten on which plates float and move.
What is oceanic crust?
A thin, dense layer of crust which lines ocean floors
What is magma?
Molten rock, gases and liquids from the mantle
What is igneous rock?
Rocks formed by cooling of molten magma
What is intrusive?
Magma that cools, crystalises and solidifies slowly below the surface
Extrusive
Lava that is in contact with air or sea.
What is gravitational sliding?
An alternative name for ridge push where lithosphere under gravity is pushed away from mid ocean ridge.
What is ridge push?
The higher elevation and mid ocean ridges causes gravity to push the lithosphere further away from the ridge.
What is slab pull?
Following subduction, the lithosphere sinks into the mantle under its own weight helping to pull the rest of the plate with it.
What is sea floor spreading?
The formation of fresh areas of oceanic crust which occurs through the upwelling of magma at mid ocean ridges and subsequent outward movement on either side.
What is subduction?
Occurs when one tectonic plate slides beneath another, moving down into the mantle.
This usually involves oceanic crust sliding beneath the continental crust.
