Our placid blue marble may look static, but Earth’s constantly shifting nature often reveals itself in dramatic fashion, as evidenced by a massive crack that recently appeared in East Africa. Last month, the crack, 50 feet wide and 50 feet deep in some places, appeared in Kenya. Geologists say the several-miles-long crack is evidence that the continent could eventually split in two.

Following heavy rains and seismic activity in the area, the crack quickly opened up on March 19, reports Face 2 Face Africa, splitting the Nairobi-Narok highway, snaking through farmland in Narok County, Kenya, and even splitting houses in two. This geological phenomenon, part of the East African Rift, gives scientists a preview of what could come in 10 of millions of years. The rift, formed by two tectonic plates — the Somalian Plate to the east and the Nubian Plate to the west — spreading apart from one another, will grow to separate the continent entirely in 50 million years, scientists predict.

This phenomenon occurred because tectonic plates, which form the Earth’s crust, don’t simply stay put. They float on top of the asthenosphere, which is viscous but also plastic, allowing the rigid plates to move around in relation to each other and push, shear, or pull apart at fault lines. The East African Rift, writes fault dynamics researcher Lucia Perez Diaz in The Conversation, is an example of how plate tectonics can eventually create new plate boundaries altogether.

“The valley has a history of tectonic and volcanic activities,” geologist David Adede tells Kenyan news outlet the Daily Nation. “Whereas the rift has remained tectonically inactive in the recent past, there could be movements deep within the Earth’s crust that have resulted in zones of weakness extending all the way to the surface.”

So even though the crack that formed in Kenya is shocking, it’s actually just a small piece of visible evidence of something that’s been happening for millions of years. The 3,700-mile-long Great Rift Valley, which runs through Kenya, formed as a result of tectonic plates drifting apart, and it may eventually flood to separate Africa from a new continent.

While residents of East Africa don’t need to worry about inhabiting a new continent anytime soon, the immediate effects of seismic activity are very real. Since the crack opened, the Nairobi-Narok highway has been filled and traffic has resumed, but residents who lost their homes will have to relocate. This incident shows that geology is slow, but only until it isn’t.