Structure of Earth
Structure of Earth
- The earth is a cold, spherical, solid planet of the solar system which spins on its axis and revolves around the sun at a certain constant distance. The solid component of earth is called lithosphere. The lithosphere is multi- layered and includes following three main layers. 1. Crust 2. Mantle 3. Core. The core is the central fluid or vapourized sphere having diameter of about 2500 km from the center and is possibly composed of nickel-iron. The mantle extends about 2900 km above the core. The crust is the outermost solid zone of the earth and it is about 8-40 km above the mantle. The crust is very complex and its surface is covered with the soil supporting varied biotic communities.
The geologic component layers of Earth are at the following depths below the surface
Depth
|
Layer
|
Kilometers
|
Miles
|
0–60
|
0–37
|
Lithosphere
|
0–35
|
0–22
|
Crust
|
35–60
|
22–37
|
Uppermost part of mantle
|
35–2,890
|
22–1,790
|
Mantle
|
100–200
|
62–125
|
Asthenosphere
|
35–660
|
22–410
|
Upper mantle
|
660–2,890
|
410–1,790
|
Lower mantle
|
2,890–5,150
|
1,790–3,160
|
Outer core
|
5,150–6,360
|
3,160–3,954
|
Inner core
|
|
Last modified: Thursday, 29 March 2012, 8:58 PM