Kilimanjaro is the highest mountain of Africa, the highest land-hosted volcano in the world, and possesses the only glaciers on the African continent – and it’s located just 3 deg south of the equator.
A stratovolcano (a volcano made of a mix of overlapping lava flows, ash, and cinder deposits that build to a conical shape), Kilimanjaro is one of about twenty volcanoes near the southern end of the East African Rift Valley. This valley is the surficial expression of a giant split developing in the African tectonic plate which will, in time, divide Africa into two new separate plates to be called the Somalian (to the east of the rift zone) and Nubian (on the west) with an intermediary “African” Ocean.
Kilimanjaro, ~80 km east of the rift valley axis, was apparently fed lava from magma sources beneath the rift valley through the intersection of a rift-parallel graben fault and cross-cutting strike-slip (future transform?) fault. The oldest parts of the volcano date to nearly a million years in age, and the youngest, the Kibo Volcano (containing the Reusch Crater visible in the photo) is just several hundred years old and still associated today with active sulfur and steam fumaroles.
The elevation of Kilimanjaro is 5895m. From base to top, it has four climate zones ranging from rain forest, to moorland, to alpine to – well, polar: it once boasted an ice sheet (dating to ~11,700 years ago) that covered the mountain down to an elevation of about 1000m. The remnants of this sheet today are glaciers and ice cliffs preserved at the highest elevations. Climate scientists predict that the days of the Kilimanjaro glaciers are numbered; possibly they will disappear entirely within the next 15 – 50 years.
Kilimanjaro then will remain a spectacular mountain, but no longer will it be that equatorial snow-capped miracle at the roof of Africa.
Photo: from http://peakware.com/ photos.html?photo=605 by B. Flemstrong.
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