The Birth of Africa’s Brand New Ocean Can Be Witnessed Right Now

Politics and country borders change all the time, but the actual physical layout of the planet was presumed to be constant, right?
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Politics and country borders change all the time, but the actual physical layout of the planet was always presumed to be relatively constant—right? Maybe not.

Well throw your globes out the window boys and girls, the field of geography is about to get exciting!

We are not talking about erosion or your average run of the mill volcano eruption. We are talking about the fact that the wheels are in motion for the creation of a brand new ocean—one forming right in the middle of Africa.

Cracks and faults that formed in September, 2005. Image: Julie Rowland, University of Auckland.

Now that’s a crack

It began in 2005. George W. Bush started his second term as 43rd President of the United States, Hurricane Katrina flooded roughly 80% of the city of New Orleans, and Mariah Carey’s “We Belong Together” topped the Billboard 100 charts. Oh yes, and a 35 mile (60 kilometer) long crack opened up in the Afar desert in Ethiopia. As far as we can tell, the previous three events were unrelated to the new fissure…but the jury is still out on Mariah.

Volcanic vent, Afar Region
Volcanic vent that opened September 26, 2006. Image: Julie Rowland, University of Auckland

The crack opened up in a matter of days, and was as much as 20 feet wide (about 6 meters) at some points.

While we tend to view geography as something that moves slowly, it turns out this isn’t always the case. Sometimes continental drift is more like a continental sprint. This particular crack opened up in a matter of days, and grew as much as 20 feet wide (about 6 meters) at some points. Let’s add some perspective: according to the web, Taylor Swift is 1.78 metres tall; so the large part of the crack is over 3 Taylor’s wide—more than wide enough to swallow the average automobile. Basically, the entire area is a “park at your own risk” zone.

Volcanic eruptions and tectonic plates; never a good combination

For the geography of a region to change this much and this quickly was pretty astonishing, but there is a reason for it. This area of Africa is on the border of two tectonic plates. These plates are divergent, meaning that they move away from each other instead of colliding with each other. In case you were absent from class that day, tectonic plates are large chunks of rock that form the lithosphere; the outer shell of the earth on which life exists (or, as some people call it—the important part). Since the lithosphere isn’t a solid shell, these plates can shift around based on what happens underneath them, and how adjacent plates shift. For example, adjacent plates can slide alongside each other, causing earthquakes; or volcanic eruptions along the edges or between tectonic plates spew out magma that can force the plates apart. This typically happens at the bottom of the ocean where we can’t see it particularly well. Changes on the surface, however, often happen too slowly for us to notice without scientific study. The case of the current rift in Ethiopia is challenging this near to invisible precedent.

Africa Crack
Central section of 60 km-long rift zone that opened south of Dabbahu volcano. Image: Julie Rowland, University of Auckland

Whether you know it or not, the movement of these plates has formed a lot of the world around us—not just responsible for many of the earthquakes we experience, this shifting has had a significant hand in the creation of mountain ranges and islands. The flexibility of the plates and their ability to shift is important though, as plate tectonics are one of the mechanisms used to release heat from earth’s molten core. If there were no plate tectonics, not only would we have no mountains, the heat from the centre of the earth might be released in an even less appealing and potentially more explosive way.

Theories on the formation of the continents as we know them now, is a bit divided—not unlike the space that separates these land masses today. Some scientists believe(d) that not so long in the past (a mere 200 million years or so ago), all the landmasses on earth were grouped together in a supercontinent named Pangea. The theory went, that the continents drifted apart across the ocean bed, relative to each other. We call this continental drift. As science brings new information to light however, this previous theory has become somewhat absorbed by the idea that there might have been “supercontinents” several times in the past. The contemporary theory is that the different plates have continually shifted around; moving apart, coming together, and moving apart again (we call this plate tectonics).

Source: Youtube / Daily Nation

Theories on the formation of the continents as we know them now, is a bit divided—not unlike the space that separates these land masses today. Some scientists believe(d) that not so long in the past (a mere 200 million years or so ago), all the landmasses on earth were grouped together in a supercontinent named Pangea. The theory went, that the continents drifted apart across the ocean bed, relative to each other. We call this continental drift. As science brings new information to light however, this previous theory has become somewhat absorbed by the idea that there might have been “supercontinents” several times in the past. The contemporary theory is that the different plates have continually shifted around; moving apart, coming together, and moving apart again (we call this plate tectonics).

In the case of the new crack in Africa, the two tectonic plates in the area are divergent, meaning that they move away from each other instead of colliding or rubbing against each other.

So how did this fracture happen? Well, it all started when a volcano named Dabbahu, located in the Afar desert erupted, essentially unzipping the tectonic plates, which was what permitted everything else to happen. 2.5 cubic kilometers of magma (that’s 2.5 trillion litres or about 660,430,130,895 gallons) forced itself up between the plates, pushing them apart and creating the fissure we now see. Just so you know, 2.5 cubic kilometres of magma is the equivalent of 1 million Olympic-sized swimming pools of red-hot fiery death. Suffice it to say, having an active volcano in the neighborhood is murder on your property values—just ask the folks in Pompeii.

Africa New Ocean
In 2005, over the course of 3 weeks, the crust on either side of the rift moved apart by as much as 8 metres. Image: Tim Wright, University of Leeds.

Slow and steady wins the race…

The movement hasn’t stopped either. While the big changes have temporarily ceased, the crack continues to expand at a rate of a bit less than two centimetres per year (about one inch per year) as additional earthquakes shake the area (12 between 2005 and 2008), and more magma is forced to the surface. The new layer of exposed crust being formed is similar to the crust that exists at the bottom of the ocean.

Professor Cynthia Ebinger, professor of earth and environmental sciences at the University of Rochester says this about the crack and what is occurring:

It’s actually not an unusual process in terms of Earth’s history. This process is happening along mid-ocean ridges worldwide. But by the time a ship is mobilized, we may have missed all of this activity. Here, this is one of the few places on the surface of the earth right now where we have this process occurring.”

The slow expansion of the crack will tear the Afar desert area and the horn of Africa away from the rest of the continent. That alone doesn’t make an ocean, but there are a number of factors at play here. The crack occurs in an area known as the Afar triangle, or Afar depression. This area contains the lowest point in Africa—Lake Asal, Djibouti—which is 155m (or 509ft) below sea level. As you can probably imagine, as soon as there is a connection between the sea and an area that is “below sea level” things start to get fun, and by fun, we really mean that maps change rapidly.

How fast can a new ocean form? Well, there’s no road map for this, but looking at the creation of the Mediterranean sea (yes, it used to be dry land during the last ice age), it is theorized that the entire Mediterranean basin might have flooded in as little as several months.
Rift areas in East Africa.

Rift areas in East Africa.

Now, you might object to us casually tossing around the word “ocean”—but how would a new body of water become classified as an ocean? The brilliant folks over at Merriam Webster define an ocean as:

a: the whole body of salt water that covers nearly three fourths of the surface of the earth

b: any of the large bodies of water (such as the Atlantic Ocean) into which the great ocean is divided

This means that for any new body of water to become an ocean, it potentially just needs to be big, and connected to the overall existing ocean system (otherwise it just become a lake). While there is no exact process for how to qualify a new ocean—let’s face it, when was the last time we had to do this?

The map of Africa is going to have a lot more blue in it

Dr. James Hammond, a seismologist from the University of Bristol and member of the research teams in Afar, explains that the only thing separating the Afar depression from the oceans is a 20-metre block of land in Eritrea. One inch per year might not seem like a lot, but 20 metres (65.5 feet) is not a large distance either in the grand scheme of things. Going back to our earlier pop music measurement scale, the sea is only separated from the crack by a little over 11 Taylor Swifts; and yes, 11 Taylor Swifts holding back the entire ocean could very well be the theme of her next music video – art does imitate life sometimes after all. As soon as a connection between land and water is established, the crack and surrounding land will take on water from the Red Sea and the Gulf of Aden, submerging the areas that are below sea level and creating a rather substantial new body of water.

Eventually the map of Africa could look a lot more like this:

Africa Rift Zones
Visualisation of how the African continent could split apart.

The crazy thing is, the split area is on a separate tectonic plate, so we’re not just talking about a new ocean, we might be talking about a new continent as well…. Maybe.

You see, the definition of continent is almost as confusing as the definition of an ocean, largely because we decided on what should be a continent before we really understood plate tectonics, and now we’re trying to make it all make sense. If we go back to our friends at Merriam-Webster, they define a continent as, “one of the six or seven great divisions of land on the globe”. The new land mass resulting from this movement will be on its own tectonic plate separate from the rest of Africa, and as you can see from the visualization above, it will be a substantial land mass. Whether it will officially be called a continent in its own right, we can’t say for sure; after all, Pluto was a planet, then it wasn’t, and we still haven’t moved past that…so let’s not place any bets just yet.

It’s going to take time

One small crack in the ground will eventually give birth to a new continent (or at least a big island) and a new ocean as well. Talk about a powerful change! Don’t grab your surfboard yet though, Professor Cynthia Ebinger estimates that it will take between 100,000 and one million years before the ocean forms. But in geographic terms, that is just the blink of an eye.


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