Geologists have discovered signs that a new ocean is emerging right on Earth’s surface. This means we could see a whole new body of water where there wasn’t one before.
So, how is this happening?
Ethiopian Desert Rift Glimpses into Earth’s Crust
In September-October 2005, a dramatic geological event unfolded in the Ethiopian Desert, as more than 163 earthquakes shook the ground and volcanic eruptions spewed ash into the sky. (ref) This activity culminated in a 35-mile-long rift tearing through the landscape.
In a 2009 study, scientists saw a rare opportunity to study a process usually hidden underwater at mid-ocean ridges, where volcanic material forms new oceanic crust.
Led by Atalay Ayele from Addis Ababa University, an early research paper suggested this “incipient oceanic rift” could eventually split the land apart.(ref)
Slow Birth of a New Ocean in East Africa
Through this rift, a new ocean could eventually form in East Africa, though geologists estimate it would take millions of years. The East Africa Rift System (EARS) is a vast network of rifts stretching from the continent’s northeast down to Mozambique.
This system, formed about 25 million years ago, lies atop shifting tectonic plates. As the Somali Plate gradually drifts eastward and the Nubian Plate remains stable, the rift could widen enough over time to create a sea within Africa.
Some valleys in the EARS have filled with water, like Lake Tanganyika, the world’s second-deepest lake. Over time, the rest might also fill with ocean water as they sink, but that could take millions of years.
Geologist Edwin Dindi told The New Times that it took over 30 million years for the Earth’s crust in the rift valley to thin from “40 to 35 kilometers (25 miles), so it will take even longer to lose another 5 kilometers (3 miles).”(ref)
For this to happen, the African and Somali Plates must separate more, but they’re currently moving apart at a rate between half an inch to 0.2 inches per year, according to Ken Macdonald, a marine geophysicist and professor emeritus at the University of California, Santa Barbara, who told NBC News.(ref)
Possible Outcomes
While geologists have observed signs that a new ocean could be forming in Africa, it could be that unforeseen events could slow down the movement of the plates, preventing the separation from completing and filling the rift with sediment. This could stop the process of a new ocean forming, making it a “failed rift.”
In The New Times article, Dindi points to a failed rift in the Northeastern part of Kenya, and the Midcontinent Rift, which stretches for about 1,800 miles through parts of the U.S. and contains ancient rocks. Though volcanic eruptions spread basalt, North America did not split.
In addition, a 2020 study describes how volcanic and tectonic activity in regions like Afar Depression (part of the Great Rift Valley in East Africa) is linked to basin formation and sediment buildup, which are early stages in the rifting process.
If the rifting continues over millions of years, it could eventually form a new ocean as the plates pull apart. (ref)
Meanwhile, the PaleoMap project by geologist Christopher Scotese suggests that in 100 million years, the Somali and African plates will collide with Europe and Asia, forming a large landmass. (ref)
As for now, researchers aren’t rushing to call the rift a new ocean just yet.
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Nancy Maffia
Nancy received a bachelor’s in biology from Elmira College and a master’s degree in horticulture and communications from the University of Kentucky. Worked in plant taxonomy at the University of Florida and the L. H. Bailey Hortorium at Cornell University, and wrote and edited gardening books at Rodale Press in Emmaus, PA. Her interests are plant identification, gardening, hiking, and reading.
