5.6 Tectonic Plates

the movement of tectonic plates are linked to a very impressive phenomena.

What is a tectonic plate?

Definition of tectonic plates: tectonic plates are the huge pieces of the lithosphere that float on the partially melted rock from the mantle. a tectonic plate can either be fully oceanic or fully continental but it can also be mixed: half continental and half oceanic.

The main tectonic plates

the plates fit together like a they are puzzle pieces. the plates that form the bottom of the oceans are the oceanic plates. most of the tectonic plates are mixed they are half continental and half oceanic.the tectonic plates cover the entire surface of the earth and they float on the partially melted rock part of the lithosphere/ the upper mantle.

How do tectonic plates move?

Definition of the movement of tectonic plates: it is caused by the very hot temperature of earth’s interior. as the tectonic plates move they can: collide/converge with each other, rub against each other and separate/diverge from each other.

Collision of tectonic plates

once the tectonic plates move in different directions sometimes they get too close to each other and collide.since the continental crust is thicker and denser than the oceanic crust when the two collide the oceanic plate dives into the mantle where part of it melts. that process is called “subduction”. subduction can also happen when two oceanic plates collide. the collision of two tectonic plates can cause a mountain range, volcanoes and earthquakes to form.

Separation of tectonic plates

if two plates collide they can also move apart. so maybe there are giant openings in the earth. tectonic plates mostly move apart at the bottom of the ocean. this movement often causes underwater earthquakes. new oceanic crust forms in the mid-oceanic ridges. this causes the oceans to expand little by little. wherever the two plates moved apart, magma slowly rises and solidifies which creates long underwater mountain ranges which are called “mid-oceanic ridges”.the separation of the tectonic plates form earth’s oceanic crust. this separation may cause underwater earthquakes which can lead to tsunamis.

Rubbing of tectonic plates

the tectonic plates may also rub against each other. the massive amount of energy released from when the tectonic plates slide past each other, this causes earthquakes.

Discovery: in the beginning of the 20th century scientists made some intriguing observations. they saw that South America and Africa seemed to fit together perfectly like a puzzle. this observation led a german scientist to develop a theory called “The origin of continents”around in 1915. over the years this theory has evolved and best explains the shape of the earth. this scientist built the foundations of what we call now “plate tectonics”. This scientist also figured out that the continents all came from one “supercontinent” called PANGEA. Now we can tell that the continents are slowly drifting apart by a few centimetres per year.