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Continental Drift Theory. Ahead of its Time. Background . It has been recognized for along time that coastlines of South America and Africa appear to fit together
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Continental Drift Theory Ahead of its Time
Background • It has been recognized for along time that coastlines of South America and Africa appear to fit together • Still it is another feature of Geology where direct information had been missing, and the thinking of individuals were much different.
In 1858, a French naturalist offered fossil evidence to support the idea that the continents were once joined, but his reasoning for the movement was Noah’s Ark and the flood associated with it.
In the late 19th century, many scientist, and others thought that continents and oceans of the Earth were stable and unmoving.
In 1908, a geologist, F.B. Taylor noted that the distribution of some of the world’s mountain chains could be explained if the continents were once joined.
Mountain belts of a similar age and rock appear to begin abruptly at coastline on the other side of the ocean. When joined, the mountain chain form a continuous belt.
Along Came Wegener • In 1915 , Alfred Wegener, published his work and studies which coined the term “ Continental Drift”. • He was not the first with the idea, but he was investigated the idea extensively, with several pieces of supporting evidence that were believable.
Wegener’s Continental Drift Theory • That all landmasses were once joined in a supercontinent, which he termed “Pangaea” • This supercontinent separated into two landmasses, the northern landmass was termed Laurasia, and the southern landmass Gondwanaland. • The landmasses have further moved and separated to where they are today.
His Evidence • Palaeontological (or fossil evidence)
Lithological or rock evidence • Mountain chain evidence , already shown.
The Trouble • Wegner had valid evidence but he did not have a reason for the movement. • What was the cause for this movement of continents? • Because of the missing element he was criticised for over 15 years. And the debate continued after his death until new evidence emerged after World War II. • The new evidence lead to the new theory- “Plate Tectonics”
