Lake Abbe is a salt lake, the largest and last of a chain of six connected lakes on the Ethiopia-Djibouti border. The lake lies on a basin called the Afar Depression at a point where the Arabian, Nubian, and Somalian plates are pulling away from each other. The strain caused by the splitting Nubian and Somalian plates has created a strange landscape around Lake Abbe. As the two plates drift apart, the crust above them thins until it cracks. Magma pushes to the surface through the thin spots and warm underwater springs. As the boiling water bubble up to the surface, they deposit the dissolved calcium carbonates creating towering chimneys, the same way water trickling down the roof of limestone caves create stalactites and stalagmites. Some of these chimneys reach heights of 50 meters, and puffs of steam vent from the top. The otherworldly landscape inspired Charlton Heston to shoot his classic 1968 film, "Planet of the Apes", on the shores of Lake Abbe.
Photo credit: George Steinmetz
The Afar Depression is fascinating to geologists because it is the place where new ocean is being formed. The depression is forming as the African plate splits into the Nubian and Somalian plates. In a few million years, the Indian Ocean will break through the coastal highlands and flood the Afar Depression, creating a new ocean and making the Horn of Africa a large island. When continental plates move apart in the ocean, it creates new sea floor, but in East Africa, the process is happening on dry ground, where it is called continental rifting.
Lake Abbe is fed by the Awash River, and seasonal streams which enter the lake from the west and south, crossing the vast salt flats. On the northwest shore rises Mount Dama Ali, a dormant volcano. Lake Abbe was once a much larger lake but diversion of water from Awash River for irrigation in the 1950s has shrunk the lake surface area by two-thirds and water level by 5 meters.
The nearest town lies 200 km away, but there is a small settlement established by the Afar people near the lake's shore. Aside from the Afar shepherds who brings their herds of sheep or donkeys to feed, the only inhabitants of this lake are pink Flamingos.
Photo credit: unknown
Photo credit: Yann Athus-Bertrand
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