The lithosphere is primarily composed of two key layers of the Earth: the crust and the uppermost part of the mantle.
The crust is the outermost layer of the Earth and varies in thickness, being thinner under oceans and thicker under continental landmasses. It consists of solid rock and is where we find landforms, oceans, and all types of geological activities.
Below the crust lies the uppermost part of the mantle, which is also solid but behaves in a more plastic manner compared to the crust. This upper mantle is integral to the lithosphere and plays a crucial role in tectonic plate movements.
Together, these two layers make up the lithosphere, which is rigid and acts as the Earth’s surface layer, supporting terrestrial life and various geological processes.