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The Great Rift Valley is part of an intra-continental ridge system that runs through Kenya from north to south. It is part of the Gregory Rift, the eastern branch of the East African Rift, which starts in Tanzania to the south and continues northward into Ethiopia. It was formed on the "Kenyan Dome" a geographical upwelling created by the interactions of three major tectonics: the Arabian, Nubian, and Somalian plates. In the past, it was seen as part of a "Great Rift Valley" that ran from Madagascar to Syria. Most of the valley falls within the former Rift Valley Province. The valley contains the Cherangani Hills and a chain of volcanoes, some of which are still active. The climate is mild, with temperatures usually below . Most rain falls during the March–June and October–November periods. The Tugen Hills to the west of Lake Baringo contain fossils preserved in laval flows from the period 14 to 4 million years ago. The relics of many hominids, ancestors of humans, were found here. ==Features== The valley is bordered by escarpments to the east and west. The floor is broken by volcanoes, some still active, and contains a series of lakes. Some of the soils are Andisols, fertile soils from relatively recent volcanic activity. Lake Turkana occupies the northern end of the Great Rift Valley in Kenya. There are also volcanoes in Lake Turkana. The Suguta Valley, or Suguta Mud Flats, is an arid part of the Great Rift Valley directly south of Lake Turkana. The shield volcano Emuruangogolak straddles the valley to the south of Suguta, and further south Mount Silali and Paka rise from the valley floor. Paka is a shield volcano, with widespread geothermal activity. South of Paka are Mount Korosi, Lake Baringo and Lake Bogoria. Menengai is a massive shield volcano in the floor of the rift with a caldera that formed about 8,000 years ago. It overlooks Lake Nakuru to the south. This region also includes Lake Elementaita, Mount Kipipiri and Lake Naivasha. The Hell's Gate National Park lies south of Lake Naivasha. In the early 1900s, Mount Longonot erupted, and ash can still be felt around Hell's Gate. Mount Longonot is a dormant stratovolcano located southeast of Lake Naivasha. Suswa is a shield volcano located between Narok and Nairobi. Lava flows from the most recent eruptions are still not covered by vegetation, and may be no more than one hundred years old. Lake Magadi is the most southern rift valley lake in Kenya, although the northern end of Lake Natron in Tanzania reaches into Kenya. The Elgeyo escarpment forms part of the western wall. The Kerio Valley lies between the Tugen Hills and the Elgeyo escarpment at an elevation of There are large deposits of Fluorite in the Kerio Valley area. Further south the Mau Escarpment is a steep natural cliff approximately 3,000 m (10,000 ft) high, running along the western edge of the Great Rift Valley about Lake Naivasha. Yet further south the Nguruman Escarpment is around 50 kilometers long and elongated in N-W direction. Its northern edge is about southwest of Nairobi, while the southern edge is near the Tanzanian border, at the northwestern corner of Lake Natron. The Aberdare Range forms a section of the eastern rim of the Great Rift Valley to the north of Nairobi. Mount Satima lies at the northern end of the Aberdares and is their highest point, and Mount Kinangop at the southern end is the second highest. The mountains form a ridge between these two peaks. Ngong Hills are peaks in a ridge along the east of the Great Rift Valley, located southwest near Nairobi. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Great Rift Valley, Kenya」の詳細全文を読む スポンサード リンク
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