Continental Drift and Plate Tectonics

Abstract

In 1912, Alfred Wegener theorized that continents were once one large continent having been broken apart over time by continental drift and provided the reasoning behind his theory as the observation of continents fitting together like puzzle pieces and sighted some fossil records as further evidence to his theory. Due to Alfred Wegener's lack of scientific testing, his theory was widely disregarded by geologists. Not until the 1950 and into the 1960's, did scientists stumble upon magnetic strips along the ocean floor that gave rise to the ability to age rock formations and formulate that the ocean floor was spreading outwardly. These studies gave rise to further observations of belts that reflected the majority of volcanic formations and earthquake activity along the ocean floor. Prior to these findings, the ocean floor was thought to be flat and motionless. Further study of these observations along the ocean floor provided scientist with plate tectonics theories that were developed and tested, and found to support, along with magnetic strip analysis, the theory of Alfred Wegener's that continental drift did occur and that plate tectonics were directly responsible for the evolution of the earth's crust.

Continental Drift and Plate Tectonics

In 1912, Alfred Wegener proposed his theory that continents that are now separate, at one time were all joined together. His hypothesis was that continents were not fixed in place but that they moved slowly over time, brought about by his observations of the larger continents that seemingly fit together like pieces of a puzzle. He hypothesized that the cause of continental drift was due to lighter rock in the form of continents, rested on heavier rock similar to an iceberg. The sea floor from the Atlantic Ridge would spread and push the lighter rock of continents from one another, slowly, into a new location. (Scwartzbach, 1986).

In testing his hypothesis of continental drift, Wegener analyzed areas on both sides of the Atlantic Ocean and on the sides of continents that seemed to fit together like puzzle pieces. He found like types of rocks and fossils. Wegener sighted his analysis of rock and fossil records as proof of his theory. However, Wegener did not formulate any further tests to provide a verifiable process in which the drift was spurred by the earth. (Trefil & Hazen, 2010).

As we know, the four steps of scientific method are: observation and description of a phenomenon, formulation of a hypothesis to explain the phenomenon, using the hypothesis to prove the observation, and performing experiments to try to prove the hypothesis. If all aspects of the scientific method are not followed, any theories are deemed to be a pseudoscience, as there is no proof to the theory that can be supported in a scientific way.

Due to Alfred Wegener's lack of providing scientific basis for how the earth's continents moved away from one another, the scientific community largely opposed and dismissed Wegener's theory of continental drift. Generally, scientists at that time believed that the earth's crust was too ridged for continents to move through it to another location, and thus, the seven major continents did not derive from one larger continent. Although Wegener's continental drift theory was dismissed for many years after initial publication, it latter planted the idea for plate tectonics theories. (Scwartzbach, 1986).

After World War II, areas of the ocean floor was mapped in a nuclear testing study. This inadvertently revealed that the seafloor was in fact continually changing; evident by canyons and large mountainous areas unbeknownst to anyone before. Further research through the mid 1960's provided data and patterns of magnetic strips along many areas of the ocean floor. Research found that the stripes had been formed along ocean ridges as magma pushed upward and took the place of older rock, pushing and moving the older rock sideways, away from the newer strip. (Trefil & Hazen, 2010). This process came to be known as seafloor spreading. The significance of these findings was that the Earth's magnetic fields changed direction over time, during which, the cooling