Treasure Trove of Ancient Human Footprints Found Near Ol Doinyo Lengai Volcano
Nine miles from the volcano the Maasai call the "Mountain of God," researchers have catalogued a spectacularly rare find: an enormous set of well-preserved human footprints left in the mud between 5,000 and 19,000 years ago. The more than 400 footprints cover an area slightly larger than a tennis court, crisscrossing the dark gray mudflat of Engare Sero, on the southern shore of Tanzania's Lake Natron. No other site in Africa has as many ancient Homo sapiens footprints - making it a treasure trove for scientists trying to tell the story of humankind's earliest days. Read more
Gas Becomes Solid at Surface of Oldoinyo Lengai Volcano Science has unearthed the secret to what might have been alchemy at Oldoinyo Lengai volcano in Tanzania. There, in the ancient East African Rift at a place known to local Maasai people as the Mountain of God, Oldoinyo Lengai spews forth carbon dioxide-laden lavas called carbonatites. The carbonatites line the volcano's flanks like snowballs. Oldoinyo Lengai is the only place on Earth where carbonatites currently erupt--and where carbon dioxide from a volcano doesn't vanish into thin air as a gas. In a paper published this week in the journal Nature, scientists report the results of a study of Oldoinyo Lengai's volcanic gas emissions, sampled by the team during a carbonatite lava eruption.
Scientists studying the world's most unusual volcano have discovered the reason behind its unique carbon-based lavas. The new geochemical analyses reveals that an extremely small degree of partial melting of typical minerals in the earth's upper mantle is the source of the rare carbon-derived lava erupting from Tanzania's Oldoinyo Lengai volcano. Although carbon-based lavas, known as carbonatites, are found throughout history, the Oldoinyo Lengai volcano, located in the East African Rift in northern Tanzania, is the only place on Earth where they are actively erupting. The lava expelled from the volcano is highly unusual in that it contains almost no silica and greater than 50 percent carbonate minerals. Typically lavas contain high levels of silica, which increases their melting point to above 900°C (1652°F). The lavas of Oldoinyo Lengai volcano erupt as a liquid at approximately 540°C (1004°F). This low silica content gives rise to the extremely fluid lavas, which resembles motor oil when they flow.
In an article published this week in the nature magazine, an international team (France-USA-Tanzania), brings back the results of a volcanic gases sampling mission to the crater of a volcano in Tanzania, Ol Doinyo Lengai (the mountain of the gods in the Masaï language), which is known to emit carbonatites, an extremely rare lava free from silica and very rich in CO2. The chemistry and the isotopic composition of gases show that CO2 comes directly from the mantle plume under the Great Rift Valley in Eastern Africa, similar to those which feed magma to the mid-oceanic ridges. The results reveal that there is a similarity to the magma plumes under the oceans and those under the continents. The abundance of CO2 is related to fusion processes and not to the composition of the magma.
In early September 2007, Tanzanias Ol Doinyo Lengai Volcano erupted, sending a cloud of ash into the atmosphere. On September 4, 2007, NASAs Terra satellite captured this image of the volcano sending a plume of ash and steam southward
A volcano in northern Tanzania erupted on Friday, spewing small amounts of smoke and lava, the government spokesman said. Mt. Oldonyo Lengai, which is close to the border with Kenya, is believed to be the source of a series of shallow earthquakes experienced in the region over the past week, said Alfred Mutua, the Kenyan government spokesman.