Tectonics Flashcards
What is the structure of the earth
In order:
Crust
Mantle
Outer core
Inner core
Properties of the crust?
This is the thinnest layer of the Earth.
• It is between 5 and 70km thick. In comparison to the whole earths radius, the crust is very thin, like an egg shell.
• It’s thinner under the oceans than it is on land. It is the coldest layer.
• It is solid rock that is broken up into pieces called tectonic plates.
• It contains rocks and minerals.
Under the oceans, the crust is mainly basalt but under the continents it’s mainly granite.
Properties of mantle?
This is the thickest layer of the Earth
• It moves in slow, big circles caused by Convection Currents
• Approximately 1000°C near the crust and 3700°C near the outer core.
• It is semi-molten (semi-liquid rock). It is made of solid rock that can flow – plastic rock
Properties of Outer Core?
The Outer Core is semi liquid iron
• Temperatures are between 3700oC and 5000oC
• Approximately 2300km thick.
• As it is iron, iron is liquid here and iron is magnetic means that the earth’s magnetic field is formed here which protects us from harmful solar winds and allows life on our planet
Properties of Inner Core? Name 2-3
Is the inner most part of the earth
• It approximately 1250km thick.
• It is the hottest part of the earth – temperatures reach over 5000oC
• Mainly made of iron and nickel – the material is under lots of pressure
• The material is very dense (4x more pressure than at the crust).
• The rock is solid in the inner core due to pressure
What is the thinnest layer of the earth
The crust
What is the thickest layer of the earth ?
The mantle
How thick is the crust
Between 5-70km thick
How thick is the outer core?
Approximately 2300km thick
how thick is the inner core?
Approximately 1250km thick
How thick is the mantle?
2900km
