Size And Structure Of The Earth Flashcards
1
Q
Outline the structure of the Earth
A
- Crust (Less dense than mantle)
- Mantle (Heavier than crust but still light)
- Core (Inner is solid, outer is molten)
- Lithosphere (Crust and upper mantle, divided into plates)
- Asthenosphere (Semi molten rock which plates float on)
- Mesosphere (Liquid rock from mantle)
2
Q
Name the 2 types of crust
A
- Continental
- Oceanic
3
Q
Give the characteristics of continental crust
A
- Thickness: 30-70km
- Age: More than 1500 million years
- Density: Light
- Composition: Light in colour. Granite
4
Q
Give the characteristics of oceanic crust
A
- Thickness: 6-10km
- Age: Less than 200 million years
- Density: Heavier
- Composition: Dark in colour. Basalt
5
Q
How do we know what the Earth is made of?
A
- Geophysical surveys (Geodesy)
- Acquisition (Satellite images)
- Geological surveys (Fieldwork)
6
Q
What is the Mohorovicic discontinuity?
A
- Boundary between crust and mantle
- Discovered as waves travel faster, indicating change in structure
