Wegener questioned why coal deposits, commonly associated with tropical climates, would be found near the North Pole and why the plains of Africa would show evidence of glaciation. The Vatican's interest began 10 years before the publication of de Revolutionibus, after a series of lectures given to Pope Clement VII on Copernicus's work.
In the s, scientists began using magnetometers to look at the magnetic properties of rocks in many locations. South America and Africa were not the only continents with similar geology , though. He kept the discussion of the plausibility of the continental drift theory going until his untimely death in during a meteorologic expedition in Greenland. For example, million year old lava flows in North America indicated that the north magnetic pole was located in the western Pacific Ocean, but million year old lava flows indicated a pole in Asia, and million year old lava flows had a pole in northern Asia. He called this movement continental drift.
He called his hypothesis continental drift. Mantle Convection Figure 3.
Researchers argued over the land bridges right up until the plate tectonics theory was developed, Frankel said. This was developed in the early part of the 20th century, mostly by a single scientist, Alfred Wegener. These include Pannotia, which formed about million years ago, and Rodinia, which existed more than a billion years ago. The Vatican's interest began 10 years before the publication of de Revolutionibus, after a series of lectures given to Pope Clement VII on Copernicus's work.
Wegener suggested that when the organisms were alive, the lands were joined and the organisms were living side-by-side. Worse, the most viable forms of the theory predicted the existence of convection cell boundaries reaching deep into the earth that had yet to be observed. Wegener understood that the rocks had formed side-by-side and that the land has since moved apart. Where two adjacent convection cells rise to the surface, a continent could break apart with pieces moving in opposite directions. One problem was that a plausible driving force was missing.
Being German wasn't Wegener's only problem; the arguments he used to support his hypothesis crossed into disciplines that were not his specialty. The answer might be sociological not scientific.
Near the surface it becomes cooler and denser, so it sinks. Anti-German bias was very strong in the 's and 's in English-speaking countries. These rocks were the same type and the same age.
The graphic below shows the striking distribution of fossils on the different continents. But Wegener discovered ancient coal seams and coral reefs in parts of the continents that were much too cold today.
Summary Alfred Wegener published his idea that the continents had been joined as a single landmass, which he called Pangaea, about million years ago. To his colleagues, his greatest problem was that he had no plausible mechanism for how the continents could move through the oceans. What do you think the problem was? He believed that the continents plowed through the crust of the ocean.
Thomas Chamberlain, suggested just that : "If we are to believe in Wegener's hypothesis we must forget everything which has been learned in the past 70 years and start all over again. Galileo needed an explanation for the lack of stellar parallax and the poor performance of his model see Galileo's Battle for the Heavens. Babb, Stanley E. His book, "The Origins of Continents and Oceans," also helped when it was published in multiple languages in , which brought it worldwide and ongoing attention within the scientific community.
Summary Alfred Wegener published his idea that the continents had been joined as a single landmass, which he called Pangaea, about million years ago. Wegener had many thoughts regarding what could be the driving force behind continental drift. Today, we know that the continents rest on massive slab s of rock called tectonic plate s. Acceptance of Continental Drift Theory When Wegener died, discussion of continental drift died with him for a while.
Currently, the field's north and south magnetic poles are very near to the Earth's north and south geographic poles.