In the concept of plate tectonics, the term "plates" refers to:
1. Oceanic crust
2. Continental crust
3. Entire mantle above the asthenosphere
Explanation:
1. Oceanic crust: This is the thinner and denser type of crust found beneath the oceans. It is formed at mid-ocean ridges and destroyed at subduction zones, playing a key role in plate tectonics.
2. Continental crust: This is the thicker and less dense type of crust that makes up the continents. Continental crust is older than oceanic crust and is less likely to subduct due to its buoyancy.
3. Entire mantle above the asthenosphere: The lithosphere, which includes both the crust and the uppermost part of the mantle, is divided into plates that float on the semi-fluid asthenosphere below. These plates interact with each other, leading to various geological phenomena like earthquakes, volcanic eruptions, and mountain formation.
Understanding the nature of these plates helps scientists explain the movement of the Earth's lithosphere and the geological processes that shape our planet.
