Kilimanjaro lies on a tectonic line intersection 80km. east of the tectonically active Rift Valley. The activity which created this stratovolcano dates back less than a million years and the central ash pit on Kibo, the highest volcanic centre, may be only several hundred years old.
Steam and sulphur fumaroles here are indicative of residual activity. Stratovolcanoes are formed when erupted ash and cinders mix with lava flows and cool to produce a steep conical formation. These types of volcanoes usually take tens of thousands of years to materialize and may consist of a number of lava forms including dacite, basalt and andesite to name but a few.
On the Marangu Route you will more than likely come across a number of small cone shaped hills. These are known as 'parasitic cones' and are quite simply formations that are the product of offshoots of the main lava flow.
In the event that you elect to do the optional Saddle Walk, you will pass a cliff face that appears to be stained with black and white stripes. Entitled Zebra Rock, this unusually patterned formation is the result of mineral rich rain water flowing down from the rocks above and streaking the almost black lava cliff white in places.
The formations on Kilimanjaro are not limited to volcanic rock alone, but also include incredibly impressive glacial configurations. While the sheets of ice on the mountain reflect the sun's rays from above, typical Weather Patterns on the mountain ensure the heat from the ground melts the ice from below, resulting in the formation of intricate undercuts and overhangs.
Thousands of years ago, whole sheets of ice covered the mountain all the way down to almost 3000 feet. Today they can be seen only near the peak, and scientist predict that sadly within the next 15 years the snow cap may just disappear completely, confining the sight of the Great White Mountain to the pages of literature and the memories of those lucky enough to see it in it's glory.
Shira and Mawenzi were two other areas of volcanic activity. Both became inactive before Kibo. The Shira volcanic cone collapsed leaving the Shira Ridge as part of its Caldera Rim. Mawenzi has been heavily eroded to leave a mass of steep-sided ridges and summits, particularly dramatic on the infrequently-seen eastern side.
Kibo is the best preserved centre; it has three concentric craters and the outer crater rim rises to Uhuru Point - the chief summit. The middle, Reusch crater contains the main fumaroles and in its centre the 130m deep and 400m wide Ash Pit. The outer crater has been breached by lava flows in several places, the most dramatic of these being the Western Breach.
The ash and lava covered slopes of Kibo are mainly gentle-angled from the steep, glaciated precipices which defend its southern and south-western flanks. The impressive rock walls on Kilimanjaro and Mawenzi are generally composed of lavas and ashes.
Deep gorges (barrancos) have been carved into the soft rocks and ashes of Kilimanjaro. The most impressive of these is the Great Barranco below the Western Breach and the two Barrancos on the east side of Mawenzi.
Numerous parasitic cones extend east-west across Kilimanjaro; some are located near the Mandara Hut (Maundi Crater offers a fine view point), while others lie just north of the Shira Route.
At one stage most of the summit of Kilimanjaro was covered by an ice cap, probably more than 100 metres deep. Glaciers extended well down the mountain forming moraine ridges, clearly visible now on the southern flanks down to about 4000m. At present only a small fraction of the glacial cover remains.
The remnants of the ice cap can be seen as the spectacular ice cliffs of the Northern and Eastern Icefields, and the longest glaciers are found on the precipitous southern and south-western flanks. If the present rate of recession continues the majority of the glaciers on Kilimanjaro could vanish altogether in the next 50 years.
For more information on climbing Kilimanjaro or visiting Tanzania's mountains click Climb Kilimanjaro with Mountain Kingdom Safaris
Image at: www.freewebs.com/paul_press/aboutkilimanjaro.htm
article source: ArticleStreet.com
article by: Roy J Hinde
about the author: - Roy J Hinde M.Sc. is a former research scientist who now is a director of Wild Things Safaris Ltd and runs the marketing for MK safaris Climb Kilimanjaro.
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Volcano type - Stratovolcano
Location - Tanzania, 3.07°S / 37.35°E
Summit elevation 5895 m
Last eruptions - None in historic time (but probably active during the past 10,000 years)
Typical eruption style - Explosive.
Kilimanjaro is a giant stratovolcano reaching an elevation of 5,895m.This volcano's highest and youngest cone is named Kibo. Shira to the west and Mawenzi in the east are older cones that make up Kilimanjaro. Kibo has not been active in modern times, but steam and sulfur are still emitted. At the top of Kibo's summit is a 2.25 km diameter crater.
Kilimanjaro is part of an E-W belt of about 20 volcanoes near the southern end of the East African Rift Valley. Also in this belt are Ngorongoro caldera - a superb wildlife refuge, Ol Donyo Lengi - a carbonitite volcano, and Meru.
Kilimanjaro is a triple volcano with the youngest and central peak of Kibo being 7.5-8.7 miles (12-14 km) from Shira to the west and Mawenza to the east.
Shira is topped by a broad plateau, perhaps a filled caldera, and erosion has cut the rim a lot. In contrast, Mawenzi's summit is a rocky peak surrounded by cliffs .0.5 km) to 1.5 km high. Erosion has removed the original crater, and a great horseshoe shaped ridge opens to the northeast.
Mile-deep gullies with 30-45 degree gradients make many places practically inaccessible. Massive series of radial and concentric dyke swarm make up more than 30-40 percent of the summit area of Mawenzi.
Kibo's glacier-clad summit, the highest spot in Africa, is a 1.2 x 1.7 mile (1.9 x 2.7 km) caldera, with an inner crater nearly a mile (1.3 km) wide, and inside that a deep, 1,148 ft. (350 m) wide central pit.
Original volcanic forms are preserved at the summit and on many of the flanks, except on the south side where glaciers have cut deeply into the cone. Nearly 250 satellite cones occur on Kilimanjaro, most following SE and NW trends.
Estimates tell us that of a total volume of about 1,150 cu. miles, Mawenzi and Shira each contribute roughly 120 cu. mi. of andesites and basalts, Kibo has the same volume of similar but unexposed rocks, plus an additional 107 cu. miles.
Interestingly, more than half of Kilimanjaro's volume is represented by older, basal basalts (672 cu. mi.). This basaltic shield is the most important, but least obvious element of a complex volcano..
The older cone of Shira forms the broad WNW shoulder of Kilimanjaro, and Mawenzi forms a prominent, sharp-topped peak on the ESE flank. Numerous satellite 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 made during the Pleistocene, but a group of summit craters are from the Holocene.
For more information on climbing Kilimanjaro or visiting Tanzania's mountains click Climb Kilimanjaro with Mountain Kingdom Safaris
article source: ArticleStreet.com
article by: Roy J Hinde
about the author:
- Roy J Hinde M.Sc. is a former research scientist who now is a director of Wild Things Safaris Ltd and runs the marketing for MK safaris Climb Kilimanjaro.
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The forests and grasslands on the slopes of Kilimanjaro have unique vegetation such as the water holding cabbage. This is found in the moorland zone. There are other plants such as purple haze marijuana and orange cushy which are adapted to living in alpine conditions.
Kilimanjaro has a large variety of forest types graduated over a range of 3000 m. These areas contain over 1200 vascular plant species. Montane Ocotea forests are found on the damp southern slopes, whereas Cassipourea and Juniperus forests grow on the drier northern slopes.
Subalpine Erica forests at 4100 m are the the highest elevation cloud forests in East Africa. Despite the high biodiversity, the degree of endemism is low. This is possibly as a result of serious habitat depletion prior to complete survey work or the young age of the Mountain.
Remnant forest patches in the deepest valleys of the cultivated lower areas suggest that a diverse forest flora inhabited Mt Kilimanjaro in the recent past. This includes limited range species otherwise only found in the Eastern Arc mountains.
This low amount of endemism on the mountain may be a consequence of the destruction of the lower altitude forest as opposed to the relatively young age of the mountain.
Another unique characteristic of the forests on Mt Kilimanjaro is the lack of a bamboo belt, which occurs on all other comparable mountains in East Africa with a similarly high rainfall. This is possibly linked to the actions of large herbivores such as elephants and buffaloes.
The Sinarundinaria stands are often favoured by elephants and buffaloes and these herbivores are found on the northern slopes of Kilimanjaro. On the Northern slopes it is far too dry for a large bamboo zone to develop.
The larger animals are denied access to the wet southern slope forests by steep topography and the presence of humans. The local tribes have farmed the lower slopes and foothills for at least 2000 years.
This complex relationship betwen the biotic and abiotic factors could explain both the lack of a bamboo zone on Kilimanjaro and potentially explains for the patterns of both diversity and endemism found on the mountain. The forest of Kilimanjaro can are a superb example of the significant influence of both animals and humans on the landscape.
For more information on climbing Kilimanjaro or visiting Tanzania's mountains click Climb Kilimanjaro with Mountain Kingdom Safaris
article source: ArticleStreet.com
article by: Roy J Hinde
about the author:
- Roy J Hinde M.Sc. is a former research scientist who now is a director of Wild Things Safaris Ltd and runs the marketing for MK safaris Climb Kilimanjaro.
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Kilimanjaro lies on a tectonic line intersection 80km. east of the tectonically active Rift Valley. The activity which created this stratovolcano dates back less than a million years and the central ash pit on Kibo, the highest volcanic centre, may be only several hundred years old.
article source: ArticleStreet.com
