Scientists have discovered a major tectonic boundary under Africa, running from Mozambique to Tanzania, called the Rovuma Transform Margin, according to multiple reports. The fossil fault, extending over 310 miles (500 km), is a remnant from the breakup of the supercontinent Gondwana during the Jurassic period, reports say. The Rovuma Transform Margin was discovered using gravity measurements from satellites and seismic reflection, according to multiple reports. The fault was buried by sediment from the Rovuma River, which changed the shape of Africa's coastline, reports say. At the margin, the crust thins by up to 18 miles (29 km) over a distance of just 10 miles (17 km), according to reports.
The Rovuma Transform Margin is a fossil fault leftover from the breakup of Gondwana during the Jurassic period, according to multiple reports. Dr Jordan Phethean described these faults as acting like railroad tracks controlling the future direction of tectonic plate movement, according to reports. He also noted that earthquakes from this prehistoric fault line would have trembled the ground beneath dinosaurs for more than 50 million years, reports say.
Africa is splitting along the East African Rift System into the Nubian and Somali plates, according to multiple reports. The Rovuma Transform Margin is not an active fault line like the San Andreas Fault, reports say, but it influences plate movement. The Somali Plate is drifting away from the rest of Africa at a rate of roughly 4.7 mm per year, according to reports.
The Turkana Rift in East Africa, part of the East African Rift System, has crust that is just 13 km thick at its center, less than half the thickness outside the rift zone, according to reports. This thinning is a hallmark of a process called 'necking', reports say. Christian Rowan, lead author of a study on the Turkana Rift, said in a press release that rifting in this zone is more advanced and the crust is thinner than previously recognized, and that Eastern Africa has progressed further in the rifting process than previously thought. He added that the thinner the crust gets, the weaker it becomes, which helps promote continued rifting. Anne Bécel, co-author of the study, said that they have reached that critical threshold and that this is why it is more prone to separate.
A new ocean could eventually form, with water from the Indian Ocean flooding the gap, according to multiple reports. However, it is unknown how long this process will take. The exact relationship between the Rovuma Transform Margin and the East African Rift System remains unclear, and there are no immediate seismic risks associated with the margin, reports say.