A plate is part of the earth's crust. There are 15 plates, the Pacific, North American, Eurasian, Indian-Australian, Antarctic, African, South American, Nazca, Cocos, Caribbean, Arabian, Anatolian, Gorda, Philippine, and Asian Plate. Continental Drift is when the plates move which they are constantly doing. The plates move half an inch to 2 inches a year. When the plates collide, they cause an earthquake. That is why if you live towards the edge of a plate, earthquakes are more common. Sometimes when they collide they can cause more dramatic things to happen. When the Indian Plate collided with the Asian around 50 million years ago and formed the Himalayan Mountains. Continental Drift is caused by the earth's rotation.
Plate tectonics is just a fancy word for Continental Drift. Continental Drift is measured in time periods. There are hundreds of time periods. They record all kinds of things. There are seven important time periods for measuring the effect of continental drift.
The Cambrian Period in which most of North America was on the equator and some of eastern north America was connected to Europe and Africa to form the continent Gondwanaland. The Cambrian Period was about 500 to 570 million years ago and lasted 70 million years.
|This is how the world looked during the Cambrian Period.|
The Ordovician Period, 500 million years ago, was when North America moved closer to Gondwanaland and most land was located below the equator. This took 70 million years.
|This is how the world looked during the Ordovician Period.|
The Devonian period, which was about 50 million years and was 395 million years ago. This was the period when North America and Europe collided near the equator. This is the period during which life started to move onto land for the first time and forests started to grow.
|This is how the world looked during the Devonian Period.|
The Pennsylvanian Period, 45 million years long and 325 million years ago, was when all the continents came together into Pangaea. The Cretaceous Period is when Pangaea broke up quickly and this is when dinosaurs came along. It was 136 years ago and lasted 71 million years.
|This is how the world looked during the Cretaceous Period.|
Last but not least there's the Tertiary Period in which the continents formed the shape they are in now. This is the period were in right now.
|This is how the world looks now during the Tertiary Period.|