The Earth's lithosphere is divided into several tectonic plates that float on the semi-fluid asthenosphere beneath. These plates are constantly moving, though very slowly, at rates of a few centimeters per year.
Tectonic plate movement is driven by several mechanisms, including:
- Mantle convection: Hot magma rises towards the surface, cools, and sinks again, creating convection currents.
- Ridge push: New crust forms at ocean ridges and cools, pushing older crust away.
- Slab pull: Dense oceanic crust sinks into the mantle at subduction zones, pulling the rest of the plate with it.
There are three main types of plate boundaries:
- Divergent boundaries: Plates move apart, leading to the formation of new crust.
- Convergent boundaries: Plates move towards each other, causing subduction or mountain building.
- Transform boundaries: Plates slide past each other, leading to earthquakes.
Tectonic plates movement is a crucial concept to understand various geological phenomena, including earthquakes, volcanic activity, and the creation of mountain ranges.