Ol Doinyo Lengai, "Mountain of God" in the Maasai language, is located in the north of Tanzania near Lake Natron and is part of the volcanic system of the Great Rift Valley in East Africa. Altitude - 2962 m. The volcano is located in a part of the fault zone, which is called Grid Sikes, where, as expected, the crust is particularly thin. This is one of the most unusual volcanoes in the world. It is the only one that spews natrocarbonatite lava.
Image credit Joanna Rigby-Jones
The composition of the lava is such that it allows the volcano to explode at sufficiently low temperatures. The melt temperature is between 510 and 600°C. It is the coldest and most molten lava in the world; it flows along the ground like water. Colour hot lava – black or dark brown, but after a few hours of exposure to air, carbonate melt brightens, and several months later it becomes almost white (so that it does not snow – as it might seem at first sight). Solidified lava carbonate – soft and brittle, easily soluble in water, apparently – so geologists find no trace of similar eruptions in ancient times.
(Sodium carbonate crystals from the lavadium carbonate) sparkle like diamonds. In the fog, on the contrary, the lava becomes almost invisible – quietly flowing down the slopes, it catches tourists by surprise, suddenly burning their shoes. This unusual volcano is very active and often erupts, which is why the entire area within a radius of 100 kilometres is constantly covered with ash. In the neighbourhood, you can also see extinct volcanoes that are like Ol Doina Lengai, but I have not seen black lava. Researchers report that the eruption of the volcano reached a height of about 1000 metres, a thick black column of ash.
Image credit: Ali
Image credit: Valentin Rüst
Image credit: lolula
Image credit: lolula
Image credit: Ched
Climbing the volcano is possible. But we will have to overcome the little trouble. Approximately half of the route passed; the promotion becomes much slower since feet are slipping back and drowning. Walking at this altitude is very exhausting. The trail was made of hardened lava, which was hard and dangerous, and volcanic ash, in which our legs sank up to our ankles. Place a layer of lava that reaches half a metre deep, and it shows through thick grass, which a few years ago covered slopes all the way to the top. Closer to the top begins to be felt. At the top is a strong and cold wind. A descent is even more dangerous than climbing the mountain.
Image credit: Tineke Speelman
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| Ol Doinyo Langai in Tanzania is the only volcano in the world that erupts natrocarbonatite lava, which is rich in calcium, sodium, and potassium but low in silica. The lava of Ol Doinyo Lengai is extremely cool and relatively fluid. Ol Doinyo Lengai alternates between eruptions of liquid lava that form lava lakes and fountains and explosive eruptions that build large cinder and ash cones. ASU-IPF-3021. Image credit: Lunar and Planetary Institute |
Image credit: Tineke Speelman
Image credit: Dorien K. uit A.
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| A "historic" photo – an eruption from one of the hornitos (small spatter cones), now buried by the new ash cone growing since September 2007 in the active crater of Ol Doinyo Lengai volcano (northern Tanzania) Image credit: Tom Pfeiffer |
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