Ol Doinyo Lengai Tanzania

Ol Doinyo Lengai, “Mountain of God” in the Maasai language, is an active volcano located in the Gregory Rift, south of Lake Natron within the Arusha Region of Tanzania, Africa. Part of the volcanic system of the East African Rift, it uniquely produces Natrocarbonatite lava

East Africa’s only active volcano, Ol Doinyo Lengai, is situated south of Lake Natron. In the Maasai, the name means the sacred Mountain of God. Mount Lengai is 878m high and it has explosive eruptions every twenty to forty years.

The last bigger eruption was in 1966, with some smaller ones in 1983, 1933, and 2007. Ol Doinyo Lengai is one of the few volcanoes without Sodium carbonate and potassium and it is the only volcano in the world that erupts Natrocarbonatite lava. This lava has almost no silicon and its temperatures are not as high as those of other lavas, approximately 500 – 600°C.

Ol Doinyo Lengai is known among geologists for its Natrocarbonatite lava, in fact, it is the only known active volcano in the world erupting this kind of lava. While it is thinner and more fluid than the fiery red lava rich in silicate minerals, it is most easily distinguished by its color: Ol Doinyo Lengai’s lava is black!

This unusual black color results from its composition and the comparably low temperature at which it erupts. While basalt based lava erupting from volcanoes in Hawaii reach scorching 1100 degrees Celsius, the Mountain of God’s cough appears rather cool at about 510 degrees Celsius.

Once it gets in contact with moisture, the lava turns white. Looking at Ol Doinyo Lengai with unsuspecting eyes, you might think its peak is covered in snow, while in fact, it is black lava turned white.

While you can climb the mountain, you need to be prepared for a tough hike: once in contact with rain, the decomposed lava rocks turn brittle and crumble easily, making the steep ascent all the more demanding.

Only a few kilometers from the mountain, scientists discovered several hundreds of ancient footprints, preserved in a mudflat near the village of Engare Sero for the past 19,000 years. One area shows so many footprints that the scientists nicknamed it the “dance room”.