Africa appears to be relatively stable geologically. However, many forces are at play beneath the surface of the continent, resulting in its break-up. And scientists claim this is proceeding faster than expected. In millions of years, this process might result in the emergence of a whole new ocean.A recently conducted scientific study, whose results were published in the journal Nature Communicationsrevealed that the key area within East Africa has entered the most important phase in this process. Scientists came to the conclusion that the Earth’s crust in the given region has become much thinner, which indicates the approaching continental break-up.Location of the continental break-up in AfricaThe processes described above are taking place within the East African Rift System, a major geological structure stretching for miles, starting from the Red Sea and continuing all the way down eastern Africa.In this area, the African tectonic plate is gradually splitting into two sections. One is called the Nubian plate and is located on the western side of the rift system. On the other hand, the Somali plate, which occupies the eastern part of the system, is slowly separating from the former one.The scientists chose the Turkana Rift Zone, situated in both Kenya and Ethiopia, as their object of study. It had already been known to be active from a geological point of view. But new evidence reveals that it has progressed much further in its development than initially assumed.Why the split is happening in AfricaBy analyzing seismic data, the thickness of the crust in the Turkana Rift has been determined, which turns out to be just 13 kilometers in some places. Meanwhile, the crust in the adjacent regions may exceed 35 kilometers in thickness.Such an observation is crucial, as it demonstrates that the area in question has reached a stage known as “necking.” Geoscientist Christian Rowan of Columbia University, who led the research, explained that rifting in this zone is more advanced and that the crust is thinner than anyone had recognized.It has become clear that as the crust gets reduced in size below 15 kilometres, it becomes weaker and stretches faster. Under these circumstances, it prepares for entering into a phase called “oceanization.”
The hidden crack splitting Africa that could create a new ocean. Image credit – Wikimedia
How an ocean is formedOcean genesis occurs due to crustal thinning, which allows magma to rise from beneath the crust. The cooling of this magma creates new ocean floors, while the gaps are filled with water, thus forming seas that eventually turn into oceans.Currently, the same geological activities are being seen in northeastern Africa’s Afar Depression, which explains why scientists are using the location to study how oceans form. According to USGSplate tectonic movement accounts for the geological forces which shape the continents and oceans over periods ranging from millions of years.Human evolution connection from Africa’s splitThese findings may be relevant not only to geology but also to palaeontology. The Turkana Rift Zone in Kenya is among the most significant regions in the search for early man. Many of the earliest hominin fossils have been unearthed here.It was discovered that the geological changes may have played a role in preserving these fossils. About four million years ago, during the necking stage of the rift, sediments started accumulating at a faster rate.This would provide the perfect environment for the preservation of bones and other fossils.It is worth mentioning that some scientists believe this is the reason behind the abundance of fossil remains in this region as compared to other regions.Understanding the “faster than expected” continent splitDespite the fact that it is happening relatively quickly, the process is occurring relatively slowly in comparison with human timescales. This is because forming an ocean takes millions of years.The scientific community stresses the point that it is not a phenomenon that can be observed during one’s lifetime. Nonetheless, the importance of the discovery should not be overlooked, as it sheds light on what was previously known about the process and helps to better comprehend the evolution of continents.Importance of the discoveryThe described discovery allows us to look into a process that is usually hidden from us. As was mentioned before, most continental breakups occurred millions of years ago. Hence, it is impossible to study them firsthand.Fortunately, the East African Rift System provides a great example of this process in action. The findings also highlight how Earth’s surface is constantly changing, even if those changes are too slow to notice in everyday life.
