What are the major components of Earth's lithosphere?
The lithosphere is the rigid outer layer of the Earth, consisting of the crust and a portion of the upper mantle. To determine the major components of the Earth's lithosphere, we need to understand the composition of both the crust and the upper mantle.
The crust can be divided into two main types: continental crust and oceanic crust. Continental crust mainly consists of granitic rocks, which are rich in silica and aluminum. Oceanic crust, on the other hand, is mainly composed of basaltic rocks, which are denser and have higher concentrations of iron and magnesium compared to granitic rocks.
The upper mantle lies just beneath the crust and is predominantly composed of a rock type called peridotite. Peridotite is rich in iron and magnesium, and is denser than the rocks found in the crust.
Therefore, the major components of the Earth's lithosphere are:
1. Continental crust: Composed mainly of granitic rocks.
2. Oceanic crust: Composed mainly of basaltic rocks.
3. Upper mantle: Composed mainly of peridotite.
These components combine to form the lithosphere, which plays a vital role in shaping the Earth's geography, tectonic activity, and the distribution of resources.