Plate tectonics is a scientific theory that describes the large scale motions of Earth’s lithosphere. Plate tectonics is a relatively new theory and it wasn’t until the 1960′s that Geologists, with the help of ocean surveys, began to understand what goes on beneath our feet.
The Earth’s surface is made up of a series of large plates. These plates are in constant motion traveling at a few centimeters per year. The ocean floors are continually moving, spreading from the center and sinking at the edges.
200 million years ago all of the present continents combined to form a single continent called supercontinent Pangea.
It initially split into two pieces. Laurasia – landmasses which today is in the northern hemisphere and Gondwana – landmasses in the southern hemisphere.
Here’s how the Earth looked like in the late Jurassic era, about 150 million years ago.
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