Plate Tectonics
Plate Tectonics is a scientific theory that describes large motions of the Earth's lithosphere. The theory is backed up by continental drift, developing during the first 20-50 years of the 20th century. Earth's lithosphere is made up of tectonic plates. There are 7-8 major plates in the lithosphere, followed by many smaller plates.
Convergent Boundary
A Convergent boundary always depends on the type of olates that are colliding in the Lithosphere. When a dense oceanic plates starts colliding with a less dense continental plate, the oceanic plate will plunge down creating a convergent boundary, also called a "Subduction zone" . Now you might wonder if ever if the oceanic plate will ever go over top of the continental plate forcing it down. Well no it doesn't. You see. there is the word "dense". Dense means the weight of something under water. So if someone says to you, the rock is more dense than the tennis ball. Dense means that its heavier, and lees dense means its lighter.
Divergent Boundary
A Divergent Boundary is when two plates from the Lithosphere(Lithosphere is where all tectonic plates are located) collide with each other, note the density is the same, both of the plates go upwards once they collide. This is pretty much like a new volcano forming because magma gets thrusted up from it.
Transform Plate Boundry
Now the third type of plate boundries that I will be describing is the transform boundry. Transform boundries are when two plates from the lithosphere slide past eachother bumping into each other while this happens. When this happens, there is usually an earthquake. One of the most recognized and popular, if you can say that, is the San Andreas Fault in South/Mid Western California. This is why there are so many earthquakes along the ocean in Southern California. Big cities that have been introduced to the San Andreas Fault would be San Francisco, Los Angles, San Jose, Oakland, and Anaheim.
Theory of Pangea
Now you wonder ans look at the picture and think, "Why are all the continents enclosed together?" well I will tell you. You see Pangea was discovered by a man named Alfred Wegner who in 1915 was looking at a world map and said to his wife "Have you ever noticed that the continents all fit in to eachother like a giant Puzzle?". Now Pangea was called a "Supercontinnent". Even you could notice that there once was a giant continnent called Pangea. There were plant and animal fossils that came from South America to Africa, plus mountain ranges and rck formations that were similar in northwestern Europe and Canada's arctic.