Oldonyo lengai Trekking.
Ol Doinyo Lengai is a volcano located in the north of Tanzania and is part of the volcanic system of the Great Rift Valley in Eastern Africa. It is located in the eastern Rift Valley, south of both Lake Natron and Kenya.
Ol Doinyo Lengai is unique in that it is the only volcano in the world that produces natrocarbonatite lava instead of a silicate one. Whereas most lavas are rich in silicate minerals, the lava of Ol Doinyo Lengai is a carbonatite. It is rich in the rare sodium and potassium carbonates, nyerereite and gregoryite. Due to this unusual composition, the lava erupts at relatively low temperatures of approximately 500-600 degrees Celsius. This temperature is so low that the molten lava appears black in sunlight, rather than having the red glow common to most lavas. It is also much more fluid than silicate lavas, often less viscous than water. The sodium and potassium carbonate minerals of the lavas formed by Ol Doinyo Lengai are unstable at the Earth?s surface and susceptible to rapid weathering, quickly turning from black to grey in color. The resulting volcanic landscape is different from any other in the world.
?Ol Doinyo Lengai? means ?The Mountain of God? in the language of the native Maasai. The record of eruptions on the mountain dates to 1883, and flows were also recorded between 1904 and 1910 and again between 1913 and 1915. A major eruption took place in June 1917, which resulted in volcanic ash being deposited up to 48 kilometres away.
When Ol Doinyo Lengai erupted on August 14, 1966, two geologists — J. B. Dawson and G. C. Clark — who visited the crater a week later, reported seeing “a thick column of black ash” that rose for approximately three thousand feet above the volcano and drifted away northwards towards Lake Natron. When the two climbed the cone-shaped vent, they reported seeing a continuous discharge of gas and whitish-grey ash and dust from the centre of the pit.
Mount Oldonyo lengai Trekking, an impressive volcanic crater cone 9,777 feet (2,980 m) high and the only remaining active volcano in this region, located in the Rift Valley, in the heart of Masaai country. Its continuous rumbling and steaming earned it its Maasai name ?Mountain of God?.
The dark peak is held in great regard in Maasai legends and traditions. Dust and ash from its eruptions, blown northwest, created the fertile Serengeti Plains.