Plate Tectonics
Plate tectonics is the theory explaining geologic changes that result from the movement of lithospheric plates over the asthenosphere (the molten, ductile, upper portion of the earth's mantle). The visible continents, a part of the lithospheric plates upon which they ride, shift slowly over time as a result of the forces driving plate tectonics. Moreover, plate tectonic theory is so robust in its ability to explain and predict geological processes that it is equivalent in many regards to the fundamental and unifying principles of evolution in biology, and nucleosynthesis in physics and chemistry.
Based upon centuries of cartographic depictions that allowed a good fit between the western coast of Africa and the eastern coast of South America, in 1858, French geographer Antonio Snider-Pellegrini, published a work asserting that the two continents had once been part of larger single continent ruptured by the creation and intervention of the Atlantic Ocean. In the 1920s, German geophysicist Alfred Wegener's writings advanced the hypothesis of continental drift depicting the movement of continents through an underlying oceanic crust. Wegner's hypothesis met with wide skepticism but found support and development in the work and writings of South African geologist Alexander Du Toit, who discovered a similarity in the fossils found on the coasts of Africa and South Americas that derived from a common source.
This is a free page. This page contains 201 words. This
article contains 1,854 words (approx. 6 pages at 300
words per page).
Read the rest of this Article with our Plate Tectonics Access Pass.
