Could Earth Ever Get a New Ocean?

By: Laurie L. Dove  | 
Massive Iceberg floating in the Southern Ocean in Antarctica with stormy seas
The most recently designated ocean was the Southern Ocean surrounding Antarctica, but there's technically just one global ocean. Ray Hems / Getty Images

Of the vast ocean that covers 71 percent of the planet, there are five distinct regions — Atlantic, Pacific, Indian, Arctic and Southern. Schoolchildren memorize their names, sailors navigate them and some of the most biologically diverse species in the world inhabit the oceans [source: NOAA].

But could Earth ever develop a new ocean? It seems unlikely, given the monopoly existing ocean regions have had on the liquid portion of our planet's surface for about 4 million years. Yet, surprisingly, the formation of this new ocean is already underway, though it'll take place in the distant future.


East African Rift Valley

Scientists expect a huge rift forming in the Ethiopian Afar desert to become the world's newest ocean. The 40-mile (64-kilometer) crack, which is sometimes more than 20 feet (6 meters) wide, sits along a boundary of Earth's shifting tectonic plates.

At the rift's northern end lies Dabbahu, a volcano whose 2005 eruption helped spawn the first 35 miles (56 kilometers) of the rift in just 10 days. After the eruption came earthquakes that caused magma — molten rock from the center of Earth — to gush up through the center of the crack, quickly splitting it in both directions.


“This is the only place on Earth where you can study how continental rift becomes an oceanic rift,” said Christopher Moore, a visiting research fellow at the University of Leeds, to NBC News.

Since that time, magma has continued to flow like hot toffee, volcanoes have continued to erupt and the deep fissure has continued to grow — albeit at a slower rate that has increased the split by several miles.


The Speed of Massive Change

Scientists are studying the process both for its remarkably fast timeline and the fact that it mirrors a tectonic processes that normally take place on the ocean floor at a depth too remote to reach.

Until 2005, the African plate and Arabian plate that border each other in the remote Afar desert had been spreading apart at a snail's pace of less than 1 inch (2.5 centimeters) per year.


In the past 30 million years, the opposing masses had only managed to form a 186-mile (299-kilometer) depression in addition to the adjacent Red Sea, but there had been no dramatic shift like the one that began in 2005 [source: LiveScience].

A Changing African Continent

Eventually, scientists expect the Afar Rift to connect the Red Sea to the north and the Arabian Sea to the south. When this happens, the Afar Rift will turn into a new ocean that will split Africa and release the Horn of Africa from its land mass, changing the future of a few landlocked countries. [source: PhysOrg].

“The Gulf of Aden and the Red Sea will flood in over the Afar region and into the East African Rift Valley and become a new ocean, and that part of East Africa will become its own separate small continent,” said Ken Macdonald, a marine geophysicist, to NBC News.


Even though we won't be around when the new ocean forms as it is only growing about as fast as a fingernail, scientists are monitoring the changes with bated breath. After all, the ability to witness a process that is typically inaccessible has the makings of a once-in-a-career opportunity.

That is, until you consider the fact that, at its current rate, this new ocean will probably take another 10 million years to fully form [source: Wright].


Lots More Information

  • LiveScience. "Giant Crack in Africa Will Create a New Ocean." Nov. 2, 2009. (Aug. 1, 2014)
  • NOAA. "There is Only One Global Ocean." (Aug. 1, 2014)
  • PhysOrg. "Witness the Birth of Africa's New Ocean." June 28, 2010. (Aug. 1, 2014)
  • Wright, Tim. "Africa's New Ocean." (Aug. 1, 2014) The Royal Society.