Scientists have discovered a massive magma ocean beneath Africa’s Afar Depression. This vast network of underground structures is actively pushing the Earth’s crust apart.
The Afar Depression of Eastern Africa is an area where you could literally see the world break into pieces. It is a mesmerising location where the Earth’s crust is slowly separating from each other, exposing the underlying mantle through jagged valleys and shimmering salt flats. For years, scientists have been watching in awe at the process of the formation of a new ocean right before their eyes in this arid region. However, what we didn’t realise until recently was that there lies a huge “ocean” of magma lying beneath the surface.The classical model of scientific theory frequently relied upon the use of a simple mental picture, which consisted of one massive magma balloon existing beneath a single volcano. But, obviously, nature is not so simplistic. In an important study featured in the scientific journal Nature Communications in 2024, scientists uncovered that the reason for the occurrence of this phenomenon was a complex network of structures known as sills, which span up to 100 kilometres inside.Visualising a network of magma structures extending over 60 milesNow, it is necessary to grasp what a structure of this magnitude really means. After all, we are talking about a large area where magma flows. This is roughly the distance from Manhattan to the eastern part of Connecticut. And there is no one source down there – it is a network.It was not through the use of pickaxes or even trowels; space satellites helped the geologists in their work. The geodesists detected the slightest quakes on the surface of the planet and found out that the whole valley breathes. Based on the data received, the scientists concluded that there are four gigantic sills buried underneath the crust of the Earth, located at a depth of 9 to 28 kilometres and expanding at the same time. Thus, there must be some energy source deep inside the Earth’s mantle providing magma in the network of channels.
This complex underground system, revealed by satellite data tracking subtle earth tremors, is actively feeding the formation of a new ocean. This groundbreaking finding reshapes our understanding of how continents rift and new oceanic crust is born.
How do oceans form?This discovery completely changes the opinion about the process of formation of the land bodies and their subsequent transformation into oceans or seas. Before, it was believed that it looked like breaking off a tree branch. However, it is much more constructive than it seemed earlier. As the crust gets thinner, the magma starts filling in the gaps and laying the basis for the future ocean bottom.The results of another study support this concept of fundamental change carried out by Nature Geoscience called A mantle magma reservoir beneath an incipient mid-ocean ridge in Afar. The researchers proved that the area had already been a huge repository of magmas formed by the process of decompression melting. However, the findings of the 2024 research go even further in suggesting that the magmas are not stored in stationary basins but rather travel along an organised regional network to create a new tectonic plate boundary.Such erupting and ripping apart that occur in the Afar Triangle are nothing but expressions of the real fight happening underground. It takes millions of years for the process of transformation to be accomplished underground. It is indeed an awakening realisation that while we are busily engaged with our lives above the surface of the Earth, the real drama of creation and destruction is happening beneath our feet.
