Dr. Nwosu's observation about finding the same type of organism's fossils on both continents provides evidence for the theory of continental drift. This theory suggests that continents were once joined together in a supercontinent, which has since broken apart and moved to their current positions.
The process that separates continents is primarily driven by plate tectonics, where the Earth's lithosphere is divided into tectonic plates that float on the semi-fluid asthenosphere beneath them. These tectonic plates can move due to convection currents in the mantle, leading to the gradual drifting of continents.
The separation of the continents can occur due to various geological processes, including:
- Seafloor Spreading: New oceanic crust is formed at mid-ocean ridges, pushing continents apart as tectonic plates move away from each other.
- Subduction: One tectonic plate can be forced under another, causing changes in continental positions.
- Rifting: Continental landmasses can be pulled apart at rift zones, which are often the precursors to ocean formation.
The process of continental drift is extremely slow, typically occurring at a rate of a few centimeters per year. Based on geological and fossil evidence, the continents could have begun drifting apart fairly rapidly after the breakup of the supercontinent Pangaea, which occurred approximately 200 million years ago during the Mesozoic era. The complete separation of continents can take tens to hundreds of millions of years.
In summary, the continents may have gotten so far apart due to the movement of tectonic plates driven by the dynamics of the Earth's mantle over millions of years, likely around 200 million years ago when they began drifting apart from their last known supercontinent configuration.
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