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Are We Seeing a New Ocean Starting to Form in Africa?

by Klemetti, E., May 8, 2020 in EOS

Although shallow magma storage at Erta Ale volcano hints at a rift-to-ridge transition, the tectonic future of the Afar region is far from certain.

Standing next to a lava lake at the summit of a massive volcano, Christopher Moore, a Ph.D. candidate at the School of Earth and Environment at the University of Leeds in the United Kingdom, could see the red haze of lava flows a few kilometers away. This might seem like a rare sight, but at Ethiopia’s Erta Ale, it’s business as usual.

Are such behaviors the first signs of a tectonic transition? This question is part of what Moore has been studying at Erta Ale. The entire Afar region in eastern Africa finds itself in the middle of changes that could split the continent, forming a new ocean basin. The magmatism at Erta Ale might be offering signs of this switch by mimicking the characteristics of a mid-ocean ridge.

Satellite image of eastern Africa, with the Red Sea and the Gulf of Aden to the east
The East African Rift valley, the Red Sea, and the Gulf of Aden are clearly visible in this Landsat 8 image, taken on 8 November 2019. Credit: NASA/Erik Klemetti

However, there isn’t agreement about how close the Afar region is to this tectonic transition. The geophysical characteristics of magma storage at Erta Ale could point to the region’s conversion to an incipient oceanic spreading center, but the petrology of the erupting lava might be telling us that we aren’t there yet.

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