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Active and Extinct Volcanoes in Kenya

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Active and Extinct Volcanoes in Kenya Geomorphology of Volcanic ACTIVE AND EXTINCT VOLCANOESMountains IN KENYA. Omondi Felix Mark ACTIVE AND EXTINCT VOLCANOES IN KENYA. THIS IS A LIST OF ACTIVE AND EXTINCT VOLCANOES IN KENYA. Elevation Location Last Name Volcanic Landform meters feet Coordinates eruption The Barrier 1032 3385 2.32° N 36.57° E 1921 Shield Volcano 3.50° N 36.042° Stratovolcano(Composite Central Island 550 1804 - E Cones) Shaitani Shaitani Cinder Chyulu Hills 2188 7178 2.68° S 37.88° E 1855 Chainu Chainu Cinder Mount Elgon 4321 14178 1.1° S 34.5° E Stratovolcano(Caldera) Pyroclastic cone(Cinder Elmenteita Badlands 2126 6975 0.52° S 36.27° E Holocene Cone) Emuruangogolak 1328 4357 1.50° N 36.33° E 1910 Shield Volcano Complex(Composite Homa Mountain 1751 5745 0.38° S 34.50° E Holocene Cones) Stratovolcano(Volcanic Mount Kenya 5199 17057 0°9 S, 37°18 E - ′ ′ Neck) Korosi 1446 4744 0.77° N 36.12° E Holocene Shield Volcano Likaiu 915 3000 2.17° N 36.36° E - Shield Volcano 0.914° S 36.446° Stratovolcano(Caldera) Longonot 2776 9108 1863 E Marsabit 1707 5600 2.32° N 37.97° E Holocene Shield Volcano Menengai 2278 7472 0.20° S 36.07° E 6050 BC Shield Volcano(Caldera) Namarunu 817 2680 1.90° N 36.27° E 6550 BC Shield Volcano Tuff Cones(Cinder North Island (Kenya) 520 1706 4.07° N 36.05° E - Cone) Nyambeni Hills 750 2460 0.23° N 37.87° E Holocene Shield Volcano Ol Doinyo Eburru 2856 9370 0.63° S 36.23° E - Complex Ol Kokwe 1130 3707 0.63° N 36.08° E Holocene Shield Volcano 0.904° S 36.292° Pumice Cones(Cinder Olkaria 2434 7985 1770 E Cone) Paka 1697 5568 0.92° N 36.18° E 6050 BC Shield Volcano Pyroclastic cone(Cinder Segererua Plateau 699 2293 1.57° N 37.90° E Holocene Cone-Pyroclastic Flow) Silali 1528 5013 1.15° N 36.23° E 5050 BC Shield Volcano South Island (Kenya) 800 2625 2.63° N 36.60° E 1888 Stratovolcano Suswa 2356 7730 1.175° S 36.35° E - Shield Volcano(Caldera) © 1993-2003 Opulithe Corporation. All rights reserved 1 ACTIVE AND EXTINCT VOLCANOES IN KENYA. 1. Mount Elgon • 1.13 N, 34.55 E • summit elevation 4321 m • Extinct Stratovolcano Mount Elgon is the second highest mountain in Kenya and is an extinct volcano. Mount Elgon is in the far west of Kenya on the Ugandan border. The woodland on the south eastern slopes merges into thick mountain forests. In amongst the forest and caves you will find elephant, buffalo and other animals. Kitum cave is famous as the place where elephant herds enter deep into the mountain each night where they excavate salt. It is possible to drive up to 3,659 meters and then hike across moorland to Koitoboss Peak. Access to Mt Elgon is from the town of Kitale. Mount Elgon is the second highest mountain in Kenya. The volcano is located 140km North East of Lake Victoria and is bisected by the Kenya-Uganda border. Approximately 8km in diameter, Mt. Elgon’s caldera is one of the largest intact calderas in the world. Concerns of volcanic activity were raised in August 2004 after gas emissions were detected in cave on the mountain.Mt Elgon Eruptions 2 million years ago Mount Elgon is an extinct shield volcano on the border of Uganda and Kenya. The mountain is named after the Elgeyo tribe, who once lived in huge caves on the south side of the mountain. It was known as "Ol Doinyo Ilgoon" (Breast Mountain) by the Maasai and as "Masaba" on the Ugandan side. It is the oldest and largest solitary volcano in East Africa, covering an area of around 3500 km².Mt. Elgon consists of five major peaks: • Wagagai (4,321m), being in Uganda. • Sudek (4,302m or 14,140ft) in Kenya • Koitobos (4,222m or 13,248 ft), a flat topped basalt column (Kenya) • Mubiyi (4,211m or 13,816 ft) • Masaba (4,161m or 13,650 ft) In 1896, C.W. Hobley became the first European to circumambulate the mountain. Kmunke and Stigler made the first recorded ascent of Wagagai and Koitobos in 1911. F. Jackson, E. Gedge, and J. Martin made the first recorded ascent of Sudek in 1890. The main peak is an easy scramble and does not require any mountaineering equipment. Other interesting features are: • The caldera — Elgon's is one of the largest intact calderas in the world • The warm springs by the Suam River • Endebess Bluff (2563m or 8408 ft) • Ngwarisha, Makingeny, Chepnyalil and Kitum lava tube caves. Kitum Cave is over 60 metres wide and penetrates 200 metres. It is frequented by wild elephants who lick the salt exposed by gouging the walls with their tusks. It became notorious for its association with the Marburg virus after two people who had visited the cave (one in 1980 and another in 1987) contracted the disease and died. The mountain soils are red laterite. The mountain is the catchment area for the several rivers such as the Suam River which becomes the Turkwel downstream and which drains into Lake Turkana, the Nzoia River and the Lwakhakha which flow to Lake Victoria. The town of © 1993-2003 Opulithe Corporation. All rights reserved 2 ACTIVE AND EXTINCT VOLCANOES IN KENYA. Kitale is in the foothills of the mountain. The area around the mountain is protected by two Mount Elgon National Parks one on each side of the international border. Mt Elgon © 1993-2003 Opulithe Corporation. All rights reserved 3 ACTIVE AND EXTINCT VOLCANOES IN KENYA. 2. Mount Kenya Mount Kenya is the sacred mountain of the Gikuyu people. Mount Kenya is the second highest mountain in Africa and can be climbed. The walk is relatively easy but you have to be careful of mountain sickness and time is needed to acclimatize. The actual summit is 5199 metres and is only reachable by climbing. Walkers can reach Point Lenana at 4985 metres and takes between 2 and 5 days. The nearest towns to Mount Kenya are Naro Moru and Nanyuki. Mount Kenya is located on the African Rift Valley. Eruptions have been infrequent in recent years, but there will be future volcanic activity. Volcanic activity extends 200 km both east and west of the main Rift Valley and is centered on the Kenya "dome". There is a diversity of volcanic rocks from acid to basic. Volcanism in the northern half of the Kenya Rift Valley began at 30 million years ago, and in the southern half it began at 15 million years ago. Before going on to describe Mount Kenya, some explanation is necessary of the different parts which make up a volcano. The neck is the channel or pipe through which molten lava from the lower crust of the earth rises to the surface. Materials discharged accumulate round the vent and build up a cone. The central depression or crater is kept clear by the explosive up rush of steam, etc. The cone is composed of lava and fragmentary volcanic materials known as ash if very fine-grained, tuff when the ash is consolidated, or agglomerate if the material is coarse- grained. These products are easily destroyed by wind and rain, so that it is only in the more recent volcanoes that we find the cones and craters still preserved. Although the main crater of Mount Kenya has long since been removed by erosion, parasitic cones of a much later date may be seen on the lower slopes of the mountain, many of which have their craters still preserved. The most resistant part of a volcano is the plug of lava which consolidates in the neck and it remains standing long after the lighter materials have been worn away. A mountain in which the plug forms the summit is sometimes known as a volcanic neck: an example is Mount Kenya. Volcanic cauldrons or caldera (as opposed to craters) are caused by subsidence, not up-building, and examples of these are Menengai, near Nakuru, and Ngorongoro (commonly, but erroneously, called Ngorongoro crater) in Tanganyika(Tanzania), which is more than 20 Kilometers across and one of the biggest caldera in the world. The crater of Mount Kenya is thought to have existed some 915 meters above its present summit (5195 meters). The peaks of Nelion and Batian consisting of the plug of the volcano, are composed of nepheline-syenite, a deep-seated igneous rock and not a lava. The various stages in the history of formation of the mountain may be summarized as follows a) Miocene or Pliocene. First eruptions of phonolite, followed by second and main eruptions of kenyte. b) Lower Pleistocene. Third eruptive stage (olivine-basalt), after a long interval between eruptions. c) Denudation, destruction of the crater, and excavation of existing valleys. d) Maximum glaciation during Lower and Middle Pleistocene, with a warmer period between during which the glaciers retreated. The glaciers on the mountain, which number ten at the present time, were first studied by Sir Halford Mackinder in 1903 and were found to end at between 44,060 and 45, 43 0meters. Dr. E. Nilsson has since concluded from the evidence of morrainesl that the glaciers formerly descended 1524 meters lower: to 3,049 meters in fact, and Dr. H. L. Sikes believes that they came as low as 2134 meters (the ice cap on Ruwenzori was lower still). Professor Gregory described fifteen glaciers on Mount Kenya, but five of these have now disappeared and, from observations and photographs taken in the last few years, it is evident © 1993-2003 Opulithe Corporation.
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