Can you explain tectonic plates?

http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Continents.shtml

Certainly! Tectonic plates are large, rigid pieces of Earth's lithosphere, which is the outermost layer of the Earth composed of the crust and uppermost part of the mantle. These plates are constantly moving, albeit very slowly, and they interact with each other at their boundaries.

To understand tectonic plates, it's helpful to know that Earth's crust is not one solid piece, but rather divided into several large and numerous smaller pieces that fit together like a jigsaw puzzle. These pieces, or tectonic plates, can be thought of as huge floating rafts on the semi-fluid upper mantle beneath them.

The movement of tectonic plates is primarily driven by the convective currents in the underlying mantle. These currents occur due to the transfer of heat from Earth's core to the surface. As the mantle material heated by the core rises, it cools and becomes denser, causing it to sink back towards the core. This circulation creates "conveyor belts" of molten rock that move the tectonic plates above.

Tectonic plates can interact at three main types of plate boundaries: divergent boundaries, convergent boundaries, and transform boundaries.

1. Divergent boundaries occur where tectonic plates move away from each other. This often happens along mid-ocean ridges, where new crust is created as molten rock from the mantle rises to the surface, cools, and solidifies. This process is called seafloor spreading. As the plates move apart, they create gaps that are filled by upwelling magma, forming new crust.

2. Convergent boundaries are where tectonic plates collide with each other. Depending on the type of crust involved, there are three types of convergent boundaries: oceanic-oceanic, oceanic-continental, and continental-continental. When two plates collide, one plate is usually forced beneath the other in a process called subduction. This can lead to the formation of mountain ranges and volcanic activity.

3. Transform boundaries occur where tectonic plates slide past each other horizontally. These boundaries are characterized by a lot of earthquakes, as the plates can become locked together due to friction, then suddenly slip, releasing energy.

Studying tectonic plates is done through various methods, including satellite imagery, GPS measurements, seismology, and geological observations. These techniques help scientists understand the Earth's structure, geological hazards like earthquakes and volcanic eruptions, and how landforms have evolved over time.

I hope this explanation helps you understand tectonic plates and how they shape the Earth's dynamic surface!