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The image below demonstrates fossil evidence that supports the supercontinent theory. For example, the yellow in this diagram represents fossils of the Cynognathus that were found in South America and Africa. 

Retrieved from https://pubs.usgs.gov/gip/dynamic/continents.html

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Drawing on Wegener's continental theory, Harry Hess noticed that the topography of the seafloor included "sharp, rugged ridges" (p.11). Fletcher et al. (2014) state that Hess predicted the concept of spreading centres which are marked by the creation of new crust when hot magma rises through the lithosphere. The other characteristic of the seafloor that he noticed and called deep-sea trenches, were characterized by the recycling of oceanic crust into the mantle due to intense heat and gravity (p.11). This movement is a result of convection currents that take place in the mantle (p.11). Convection currents move in a circular motion and as heated magma rises, it drags the plate along with it as it cools and falls deeper into the mantle (p.72). 

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In the image below, the outlines of plate boundaries and the continents are visible. The arrows are situated on the plate boundaries and depict the direction of plate movement are situated on the plate boundaries.

United States Geological Survey. (2014) A tectonic plate map for HKDSE Geog.svg [Digital image]. Retrieved from https://commons.wikimedia.org/wiki/File:Tectonic_plates_for_HKDSE_Geog.svg

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