Immagine

Kilimanjaro: Features of the Stratovolcano of Tanzania, the Highest Mountain in Africa

Located in the Tanzania north-eastern bordering the Kenya inside the national park of the same name, the Mount Kilimanjaro (or Chilimanjaro) with his 5895 meters of altitude It is the highest mountain on the African continentas well as the largest isolated mountain in the world, that is, not associated with mountain ranges. However, the “Roof of Africa” ​​is not a simple mountain, but a stratovolcano in a quiescent state on whose summit are present three cratersShira, Mawenzi And KiboThe origin of Kilimanjaro is associated with the East African Rift Valleywhich is slowly separating the continent in two.

Features of the Roof of Africa: One of the Highest Volcanoes on the Planet

The Mount Kilimanjaro is located in the region North-Eastern Tanzaniainside the Kilimanjaro National Parka vast plain that extends for over 75,570 hectares and from which the stratovolcano rises, with a difference in altitude of approximately 4,877 metresThe park, a nature reserve since 1910, has been declared UNESCO heritage in 1987.

Above sea level, the summit of Kilimanjaro reaches 5895 metersmaking it the highest mountain in Africa and earning it the nickname “Roof of Africa“. It is about 696 metres higher than the second highest mountain on the continent, the Mount Kenya. It is also the highest single or isolated mountain in the world, as it is not part of a mountain range. On the contrary, Mount Everest and the K2respectively the first and second highest peaks in the world, belong to the Himalayan mountain rangeThe base of Kilimanjaro has a diameter of over 40 km.

However, Kilimanjaro is not a mountain in the strict sense of the term, but a stratovolcano sleepingone of the largest in the world. At its summit there are three volcanic craters. The oldest, the Shirais located in the west and reaches 3962 meters in height. Mawenzilocated in the eastern part of the building, reaches a height of 5149 meters. In the end, Kibo, the most recent and the highest of the three craters, is located in the centre of the volcanic edifice.

Image

Origin of Kilimanjaro and latest volcanic activity

Kilimanjaro is one stratovolcano and therefore it was formed by the accumulation of lava flows and pyroclastic material over time. The origin of this imposing volcanic building is attributed to the rise and lava flow along the East African Rift Valley systema fracture in the Earth’s crust that extends for more than 6400 kmfrom Jordan to Mozambique, and which marks the breaking point of the African Plate in the plates Somali And NubianThe Rift Valley is a region geodynamically active, along which the two plates are moving gradually separating at a speed between 5 and 7 mm per yearThe separation process began about 22-25 million years agoIn the Mioceneand continues to this day.

Geographical diagram of the African Rift Valley. The red triangles represent the main volcanic edifices along the rupture zone, including Kilimanjaro. Credit: Wikimedia Commons.
Geographical diagram of the African Rift Valley. The red triangles represent the main volcanic edifices along the rupture zone, including Kilimanjaro. Credit: Wikimedia Commons.

It is estimated that Kilimanjaro volcanism began around a million years ago. About 750,000 years ago, a strong eruptive phase would have given birth to the crater Shira, active until 250,000 years agowhen its collapse occurred and a caldera. The crater Kibothe youngest of the three, is thought to have formed around 460,000 years ago. The last documented eruptive activity of the volcano dates back to Pleistocene, between 150,000 and 200,000 years ago. Despite being dormant, it has been documented fumaroles near the Kibo crater. This indicates that the possibility of future volcanic activity, although unlikely, is not entirely nonexistent.

Climatic zones, fauna and flora

Kilimanjaro National Park, thanks to its size and altitude, is characterised by five main climatic-ecological zones. The “Growing area” is located at the exit of the two main settlements, the cities of Arusha And Moshiand reaches an altitude of 1800 meters. During the year, temperatures vary between 21 and 32 °C Of day and between 4 and 15 °C at night. In this area, human activity is predominant. In fact, the nutrient-rich volcanic soil is ideal for theagriculture andfarm.

The “Rainforest area” extends from 1800 to 2800 meters above sea level. This band is characterized by very high humidity levels and rainfall that varies between 1000 and 2000 mm per year. The forest is home to numerous species of animals, including monkeys, baboons and especially birds, in addition to the rich local flora.

With a landscape reminiscent of the Scottish Highlands, the “moorland and heathland area” extends up to 4000 meters above sea level. Night temperatures here can drop below freezing. As you climb, the flora becomes smaller and thinner, with the most prominent plants being the Senecio and the Giant Lobelias, both endemic of the region. Very few animals live in this area; occasionally you can see elephants and small antelopes passing through. Sometimes, large birds of prey fly over the area.

The “Alpine desert area” extends up to 5030 meters altitude. Here day and night temperatures can drop to -12°C. This region is quite arid and inhospitablewith generally rainfall less than 250 mm per yearThe landscape is dominated by rocks volcanic.

The “arctic zone” extends up to the top of the stratovolcano. Daytime temperatures drop below -15°C, while the night ones can exceed the –26°C. The desert landscape is dominated by imposing perennial glaciers. There is no animal or plant life, except for some lichens and mosses.

A glacier on the roof of Africa. Credit: Kilimanjaro National Park
A glacier on the roof of Africa. Credit: Kilimanjaro National Park

Trekking on Kilimanjaro: How many days to climb it?

The summit of Kilimanjaro was first conquered in 1889 from Hans Meyer And Ludwig Purtscheller, and since then it has become one of the most popular destinations for Alpine hiking enthusiasts, with an influx of visitors that varies between 30,000 hey 50,000 climbers per year.

Generally, the best time to tackle the climb is between December and March, or between June and October, during the dry seasons. There are seven different paths leading to the summit, theUhuru Peakmost of which begin in the southern portion of the mountain. The shortest, known as the Marangu Trailis also the oldest of the routes, but is considered the most difficult. Its completion requires between 5 hey 6 dayswith a distance traveled of approximately 82 km and a difference in altitude of over 4,000 meters from the first base campThe other routes require more days, but generally have a less steep slope, also allowing easier acclimatization to the high altitudes, where oxygen is rarefiedOn average, longer routes can take up to 9-10 days.

Bibliography

Albino, F. and Biggs, J., 2021. Magmatic processes in the East African Rift system: insights from a 2015–2020 Sentinel‐1 InSAR survey. Geochemistry, Geophysics, Geosystems, 22(3), p.e2020GC009488. Martin-Jones C, Lane C, Van Daele M, Van Der Meeren T, Wolff C, Moorhouse H, Tomlinson E, Verschuren D, 2020. History of scoria-cone eruptions on the eastern shoulder of the Kenya–Tanzania Rift revealed in the 250-ka sediment record of Lake Chala near Mount Kilimanjaro. Journal of Quaternary Science 35(1-2) 245–255. Nonnotte, P., Guillou, H., Le Gall, B., Benoit, M., Cotten, J. and Scaillet, S., 2008. New K–Ar age determinations of Kilimanjaro volcano in the North Tanzanian diverging rift, East Africa. Journal of Volcanology and Geothermal Research, 173(1-2), pp.99-112. Richard, J.J., 1945. Kilimanjaro: crater fumaroles of Kibo and seismic activity during 1942-45. Nature, 156(3960), pp.352-354.