THEORY OF CONTINENTAL DRIFT

Theory of continental drift is a theory that describes the breaking and moving apart of continents according to Alfred Wegener. The German meteorologist, Alfred in 1912 published a theory (or idea) that all continents were once joined together in one large super continent or super large land mass which he called Pangaea surrounded by super large ocean known as Panthalassa. About 200 million years ago, Pangaea broke into two large continents or blocks: Laurasia (the northern block) and Gondwanaland (the southern part). These two blocks were separated by a narrow sea known as the sea of Tethys.

Later these two blocks somehow split up and the various continents, as we know them drifted apart. The process of splitting and movement of the “plate” of Pangaea is called Continental Drift

As the continents split and moved apart, water from the super ocean was filling the weathering gaps between the moving continents. This is how the oceans are behaved to have been formed. Presently the continents are still moving different directions.

Map of continental drift

Evidence of continental drifting

• The continents that spited and drifted thousands of kilometers apart could be refitted like a jigsaw puzzle. For instance, the Northern East coast of south America could fit into curved coastline of west Africa.
• Rocks of similar age have been identified on both continents on opposite sides of the Atlantic Ocean at points, which could be made to match each other as a jigsaw puzzle for instance, rocks of the Sahara shield (200 million years old) have been found to match with similar rocks on the Guyana shield.
• Traces of glaciation dating back from the carboniferous period have been found in the far separated landmasses of the former Gondwanaland for instance, similar glacial stations occurring on both the southern tips of south Africa and south Americans.
• Similar species of past plants and animals have been discovered on the different continents in the southern hemisphere

This has led to the conclusion that there must have existed a very wide land connection between south Africa, India, Australia and Antarctica for a long period of time.

THEORY OF PLATE TECTONIC