- Coastlines of Africa and South America join together like a jigsaw
- Fossils are found deep underground or high up in mountains.
- Radio active decay in the mantle produces enough heat for convection currents.
- Fossils of very similar plants and animals have been found on opposite sides of the Atlantic Ocean.
- The rocks match - Broad belts of rocks in Africa and South America are the same type
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Continental ice sheet covered parts of South America, southern Africa, India, and southern Australia.
At the time none believed his theory as:
- No-one could provide a good explanation of how whole continents could move apart.
- Wegener was not a geologist - he trained as an astronomer and meteorologist.
- There were other, simpler, explanations for the same evidence.
- It was felt his idea was too big for the evidence at hand.
Yet today, scientists believe that 200 million years ago, yes, the Earth's continents were joined together to form one gigantic supercontinent, called Pangaea (proving Wegener’s theory right). As the rock plates that the continents sit on moved, the supercontinent broke up over millions of years and began to move apart which is what we now see today.
The theory of plate tectonics was developed in the 1960's. This theory explains the movement of the Earth's plates and also explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and other geologic phenomenon. Plate tectonics mean the movement of plates and the activity inside the earth. The Earth is made up of four layers; inner core, outer core, mantle and crust. The crust and the mantle are the ones responsible for tectonic plates. Tectonic plates are huge areas of the Earth, which float on the mantle, they are constantly moving and hitting against each other even though we never really feel them. When the collision is strong, it makes the Earth’s crust unstable and they overlap each other. This crashing can cause mountain ranges, earthquakes or volcanoes. And when this collision happens under sea, it causes things like tsunamis and sea trenches. The plates are moving at a speed that has been estimated at 1 to 10 cm per year. Most of the Earth's seismic activity (volcanoes and earthquakes) occurs at the plate boundaries as they interact. Continental drift only occurred because of the tectonic plates.
In conclusion I believe that yes, continental drifting is a fact, evidence I have collected have shown me that. I believe that Alfred Wegener’s theory of Pangaea is true and this was due to the tectonic plates. If the plates didn’t move how else would we have mountains and volcanoes? Also it is too convenient that the plates fit together so easily if they were never together as one. Also volcanoes and mountain ranges are often on these plate boundaries explaining how they were formed.
