Final answer:
The theory of plate tectonics states that the Earth's lithosphere is divided into plates that move over the mantle, causing geological features and phenomena such as earthquakes and volcanic activity through mantle convection currents.
Step-by-step explanation:
The theory of plate tectonics states that the Earth's lithosphere is divided into tectonic plates that move. This concept is fundamental to the field of geology, akin to the role of evolution in biology or gravity in physics. It explains the motion of the Earth's crust and the upper mantle, where these plates float on the hotter, more fluid asthenosphere below.
Tectonic plates can move apart, collide, and slide past one another, causing geological phenomena such as earthquakes, mountain formation, and volcanic activity. The theory also sheds light on the reconstruction of Earth's geological history, including the formation of continents and ocean basins.
The energy required for this dynamic movement comes from the mantle's convection currents, driven by the heat escaping from Earth's interior. These currents act as a planetary cooling system, moving the warmer material upwards and cooler material downwards, thus enabling the tectonic plates to shift and reshape the planet's surface over millions of years.