By ExploreNow Editor, on February 12th, 2012%
Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 2010 (continuing)
Summit Elevation: 2962 m 9,718 feet
Latitude: 2.764°S 2°45’49″S
Longitude: 35.914°E 35°54’51″E
The symmetrical Ol Doinyo Lengai stratovolcano is the only volcano known to have erupted carbonatite tephras and lavas in historical time. The prominent volcano, known to the Maasai as “The Mountain of God,” rises abruptly above the broad plain south of Lake Natron in the Gregory Rift Valley. The cone-building stage of the volcano ended about 15,000 years ago and was followed by periodic ejection of natrocarbonatitic and nephelinite tephra during the Holocene. Historical eruptions have consisted of smaller tephra eruptions and emission of numerous natrocarbonatitic lava flows on the floor of the summit crater and occasionally down the upper flanks. The depth and morphology of the northern crater have changed dramatically during the course of historical eruptions, ranging from steep crater walls about 200 m deep in the mid-20th century to shallow platforms mostly filling the crater. Long-term lava effusion in the summit crater beginning in 1983 had by the turn of the century mostly filled the northern crater; by late 1998 lava had begun overflowing the crater rim.
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Originally posted 2010-08-20 05:00:23.
By ExploreNow Editor, on February 2nd, 2012%
Volcano Type: Stratovolcano
Volcano Status: Holocene
Last Known Eruption: Unknown
Summit Elevation: 5895 m 19,340 feet
Latitude: 3.07°S 3°4’0″S
Longitude: 37.35°E 37°21’0″E
Massive Kilimanjaro, Africa’s highest mountain, consists of three large stratovolcanoes constructed along a NW-SE trend. The ice-capped, 5895-m-high summit towers 5200 m above the surrounding plains. Activity at the older cone of Shira that forms the broad WNW shoulder of Kilimanjaro began during the Pliocene, and the extensively dissected Mawenzi forms a prominent, sharp-topped peak of Pleistocene age on the upper ESE flank dominated by a densely packed radial dike swarm. More than 250 satellitic cones occupy a rift zone to the NW and SE of Kibo, the central stratovolcano. A 2.4 x 3.6 km caldera gives the summit of Kibo an elongated, broad profile. Most of Kilimanjaro was constructed during the Pleistocene, but a group of youthful-looking nested summit craters are of apparent Holocene age, and fumarolic activity continues.
 Kilimanjaro Click Here For The Rest Of Kilimanjaro, Tanzania
Originally posted 2010-08-08 04:35:57.
By ExploreNow Editor, on December 18th, 2011%
Volcano Type: Caldera
Volcano Status: Radiocarbon
Last Known Eruption: 1450 ± 40 years
Summit Elevation: 2622 m 8,602 feet
Latitude: 8.97°S 8°58’0″S
Longitude: 33.57°E 33°34’0″E
Ngozi caldera is the most prominent volcanic feature of the Poroto Ridge, a transverse structure at the northern end of the Karonga basin. The trachytic-to-phonolitic volcano contains a 3-km-wide caldera with a 1.5 x 2.5 km caldera lake that is bounded by steep-walled cliffs 150-300 m high. Numerous pyroclastic cones are situated along the ridge. Eruption of the Kitulo Pumice, radiocarbon dated at about 10,200 cal. years Before Present, is though to be related to formation of the caldera. The youngest activity appears to have originated from the caldera and from youthful-looking pyroclastic cones to the north; the youngest known eruption produced a pyroclastic flow that swept at least 10 km to the south about 500 years ago.
 Ngozi caldera Originally posted 2010-10-28 04:10:59.
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