WE really are one world, according to the findings of AlfredWegener, a guy who really knew his weather. Born on Nov. 1, 1880, in Germany, he received a Ph.D. in astronomy from the University of Berlin, butWegener was really interested in geophysics – the science of the earth. He was especially interested in the new study of meteorology.
He pioneered the use of balloons to study air circulation. In 1906, he and his brother Kurt broke the world’s balloon endurance record, staying aloft for 52 hours. That same year,Wegener realized his dream of studying weather in the Arctic. His textbook, “The Thermodynamics of the Atmosphere,” based on his lectures, has become the standard.
As much as he liked to study the weather,Wegener is best known today as the father of the continentaldrift theory and the early theory of plate tectonics (the movement of the Earth’s plates). He presented his theory in 1912, after finding identical fossils on land separated by the Atlantic Ocean. His 1915 book, “The Origin of Continents and Oceans,” outlined his theory in detail.Wegener was not the first to suggest that the continents were once connected, but he was the first to present evidence of how the drift happened.
His idea, which was much ridiculed at the time, is now accepted by mainstream geologists thanks to evidence presented in the 1960s of the spreading of the sea floor. The volcanic activity of the mid-Atlantic Ridge and the East Pacific Rise could certainly create enough heat to cause the sea-spreading thatWegener’s theory suggested.
How does sea floor-spreading occur? It starts with a rift, formed when the Earth’s crust and shell begin to pull apart. The crust heats up, usually due to volcanic activity. This makes the crust less dense and easier to move. The crust bows upward toward the surface. The spreading continues and the rift system forms three arms, resulting in new crust forming and an ocean basin developing.
With respect to this, the old term continental drift is not 100 percent correct, because the land masses do not actually drift through the water to new locations. Both land and water move.
The spreading can stop at any time. The Red Sea is an example of a rift. It divides Saudi Arabia from Egypt and Sudan, but has not yet separated them.
Wegener’s theory states that 250 million years ago, the land that makes up our continents (North and South America, Antarctica, Africa, Australia, Asia and Europe) was once one great land mass, or supercontinent, which he called Pangaea, meaning “all Earth.” During the Jurassic Period, the great land mass was broken apart by the spreading of the Earth’s sea floor. If you look at Pangaea, you can see that the continents fit together like a giant jigsaw puzzle. New Jersey actually touches North Africa. Imagine the dinosaurs being able to walk from Antarctica to Australia!
Pangaea was formed by the collision of land masses Gondwana, Euramerica and Siberia. About 180 million years ago, Pangaea broke into two masses, Laurasia to the north and Gondwana to the south. Gondwana broke into Antarctica, the Americas, Africa, Madagascar, Arabia, Australia, New Zealand and India.
Laurasia broke into most of North America, Baltica, Siberia and China. Eurasia is our modern-day supercontinent, consisting of Europe and Asia.
AlfredWegener died on Nov. 2, 1930, while in Greenland studying polar air circulation, some 30 years before his continental-drift theory was validated.
Wegener has finally received the credit he deserves. Scientists believe that Pangaea was not the first supercontinent. Pannotia was formed some 600 million years ago. It split 50 million years later. Older still is Rodinia, which formed 1.1 billion years ago and divided 750 million years later.
Studies now suggest that super continents break up and reform about once every 250 million years. The continental plates move about as fast as a fingernail grows.
NEW YORK POST ACTIVITIES
USE the Internet or reference book to learn more about the continental-drift theory and Pangaea.
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STUDY a map of Pangaea and see if you can pick out the seven continents.
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WRITE an essay on what you think life would have been like if the continents had
not separated.
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DRAWyour own supercontinent configuration. Be sure to use all seven continents in your drawing.