In this section, we explore how the matching shorelines of continents, particularly the Atlantic Ocean's coastlines, point towards the idea that continents were once joined. Notable contributions to this theory originate from key figures like Abraham Ortelius and Antonio Pellegrini, culminating in the formalization of the 'continental drift theory' by Alfred Wegener in 1912. Wegener proposed that all continents once formed a single supercontinent known as Pangaea, surrounded by the mega-ocean Panthalassa.
Evidence supporting this theory includes:
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Jig-Saw Fit of Continents: The coastlines of Africa and South America exhibit a puzzling similarity, suggesting they were once connected.
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Rocks of the Same Age Across Oceans: Radiometric dating reveals that ancient rock formations match across the Atlantic, indicating that they were once part of the same landmass.
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Tillite Evidence: Similar glacial deposits found in southern continents indicate shared climatic histories when landmasses were together.
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Placer Deposits: The distribution of gold deposits in Ghana linked to Brazil points towards geological connections.
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Fossil Distribution: Identical species found on separated continents suggest these landmasses were once contiguous.
Finally, Wegener's theory prompted discussions about the mechanisms behind movement with ideas of pole-fleeing and tidal forces. However, alternative theories like convection current theory and sea floor spreading later built upon initial conceptions to establish modern plate tectonics.