Natural Catastrophes Caused by Plate Tectonics - Essay Example

Another proof of the theory is that coal deposits usually associated with tropical areas are also found near the North Pole, and that signs of glaciations are evident in the plains of Africa. A third proof is the presence of fossils of exactly the same species during the prehistoric times are located on the earth in the spots where one would find them if the Continental Drift Theory were true. (Sant, 2010) Wegener’s explanation for the Continental Drift Theory is the “centrifugal force caused by the rotation of the earth” and “the ‘tidal argument’ based on the tidal attraction of the sun and the moon” (Sant, 2010).

In short, Wegener hypothesized that either or both the rotation of the earth and the pull of the tides caused the continents to drift. However, he did not have any explanation for how exactly the continents were able to move. He met with opposition from fellow scientists who said that the centrifugal and tidal forces were too weak to to move continents (“Alfred Wegener,” 2011). However, the reasons for the opposition were perhaps because there was a great anti-German bias in the 1910’s and that his work was discredited because his training was more on astronomy and not geology.

(Sant, 2010) Theory of Plate Tectonics (Theory, Evidence) The Plate Tectonics Theory originated in 1915 as an answer to the weaknesses of the Continental Drift Theory (Glasscoe, 1998). However, by the 1960’s, the theory has been widely accepted by scientists. The one principle on which the Plate Tectonics Theory lies is that “both continents and ocean floor form solid plates, which ‘float’ on the asthenosphere [and thus move]” (“Alfred Wegener,” 2011). The asthenosphere is the molten, viscous liquid rock on which the plates move and is the one causing all the movements of both seafloor and continent.

(“Alfred Wegener,” 2011) Evidence for the Plate Tectonics Theory include fossils of similar species found in continents that have now separated as well as evidence provided by paleoclimate studies which reveal signs of glacier formation in parts of the world that are now geographically separated (Glasscoe, 1998). Another evidence is the age of the crust. In Plate Tectonics Theory, “the farther away you travel from a ridge, the older the crust is, and the older the sediments on top of the crust are” (“Alfred Wegener,” 2011).

This is one fact that the Continental Drift Theory was not able to account for. If all land masses separated from Pangaea, then the land must be as old as each other, but how come the ages of these land masses are different from each other? (“Tectonic Plates,” 2011). Thus, the Plate Tectonics Theory is more plausible than the Continental Drift Theory. Characteristics of Tectonic Plate Boundaries (Divergent Boundaries, Convergent, Transform Fault Boundaries, Earthquakes, Volcanoes, Mountain Building) Based on the Plate Tectonics Theory, plates are created through “rifting” or the separation of a continental crust leading to the formation of a “diverging plate boundary.

” The formation of the divergent plate boundary occurs in four steps. First, the rift valley begins to expand from the pressure coming from the asthenosphere. Second, two continental plates result from the continuous expansion of the rift valley with the molten rock continually pushing the crust apart. Third, water collects in the middle forming a sea. Fourth, the