Geography Flashcards
Tectonic Plates
Earth’s hard outer part is broken into big slabs called tectonic plates
Oceanic Crust
Crust under the oceans
Continental
Crust
The crust that forms the land is called continental crust
Convection
current
Soft rock is heated from below, the warmer rock rises through the mantle
Constructive
plate boundary
Two plates move apart, e.g. Mid-Atlantic Ridge
Destructive plate
boundary
An oceanic plate collides with a continental plate, e.g. Nazca and South American plate
Conservative
plate boundary
Two plates slide past one another, e.g. Pacific
plate and North American plate
Focus
Where an earthquake begins
Epicentre
The area directly above an earthquake. This is where the most damage occurs.
Seismic waves
The energy of the earthquake
Crust
- Thinnest layer of the Earth, between 6 - 50km thick.
- It is thinner under the oceans than it is on land.
- It contains rocks and minerals.
- It is broken into several different sections called “tectonic plates”.
Mantle
- The thickest layer of the Earth (2900km).
- This is made of solid rock that can flow (plastic rock)
- It moves in big circles caused by “convection currents”. This is where the hot rock rises and the cold rock sinks
Outer and Inner Core
- Made of mainly iron and nickel.
- The outer core is liquid.
- The inner core is hotter, but the metals are solid.
- The outer core is where the magnetic field comes from – this makes compasses work!
- The outer core is 2220km thick.
- The inner core has a radius of
1260km
Name the parts in the cross section of the Earth from inside to out
Inner Core
Outer Core
Mantle
Crust