Earth: A portrait of a planet - Introductory Notes

Question 1

Define the Geosphere

Answer 1

The Earth itself.

Question 2

Outline Earth’s Internal structure/Geosphere

Answer 2

Crust

Mantle

Core

Mantle

Crust

Question 3

Outline the structure of the geosphere - in detail.

Answer 3

Lithosphere - 100 to 150km thick semi rigid shell. Covers the crust and the highest part of the mantle.

Asthenosphere - Under the lithosphere

Question 4

Outline the history of Tectonic theory

Answer 4

First proposed by Meteorologist Alfred Wegener in 1912 while in Greenland.

Was eventually accepted as a concept in the 1960s.

Question 5

Outline tectonic theory

Answer 5

The crust and uppermost/top part of mantle form a 100 to 150km thick semi rigid shell. (Called the lithosphere).

Lithosphere is setup in distinct boundaries called plates, which move very slowly. (Over the softer Asthenosphere).

Question 6

Define the Earth system

Answer 6

The way that Earths contents interact. The planets interior, solid surface, oceans, atmosphere and life all interact with one another.

Question 7

Earth is a planet, but how does it differ from most of the other planets in our solar system?

Answer 7

Having plate tectonics, an oxygen rich atmosphere, liquid water oceans and life.

Question 8

Outline Internal and External processes.

Answer 8

Internal processes are driven by heat from inside the earth/geosphere. Examples of internals processes are tectonic movement, and as a result earthquakes and volcanoes are too.

External processes are ones driven by energy/heat coming to the earth from the sun. This energy/heat drives the movement of air and water, Causing sedimentary processes.

Question 9

How old is the Earth?

Answer 9

4.56 Billion years