JOS PLATEAU

formerly Bauchi Plateau, tableland in Plateau State, central Nigeria, distinguished by its high bounding scarp and by bare grassland and embracing Africa's chief tin-mining region. Its central area covers about 3,000 sq mi (8,000 sq km) and has an average elevation of 4,200 ft (1,280 m); the surrounding high plains often exceed 3,200 ft. The adjoining highland area on the east is occasionally designated the Bauchi Plateau. The Jos Plateau is composed of eroded gneiss formations, with granite intrusions forming massifs, and has numerous extinct volcanic cones surrounded by basaltic flows, especially around Panyam in the south and around Vom and Miango in the west, including several containing crater lakes. Its highest points are Mt. Shere (5,843 ft) and Peak Sara (5,544 ft) in the Wadi Hillsboth near Jos town. The plateau has a cool rainy climate and is the source of numerous rivers, including the Kaduna, Karami, and N'gell, which feed the Niger River; the Mada, Ankwe, Dep, Shemanker, and Wase, which flow to the Benue; the Lere, Maijuju, and Bagei, which supply the Gongola; and the Kano, Delimi, Bunga, Jamaari, and Misau, which intermittently nourish Lake Chad. The plateau's steep, irregular southern slopes have many waterfalls, notably the Gurara Falls; several are harnessed for hydroelectric power. The Jos Plateau has been inhabited since the Acheulean period of the Early African Stone Age, as shown by the hand axes found near Jos town. Discoveries of Nok figurine sculptures in the area since the 1930s have proved that Nok, the best-known West African Stone Age culture, flourished there from about 900 BC to AD 200. In the early 19th century, the population of the plateau increased as various non-Muslim groups fled to its hills to escape the ravages of the mounted warriors of the Fulani jihad (holy war). These small independent groups include the Birom, Jerawa (Jaranci), Mama, Angas, and Ron (Baram) peoples; they were never organized into a traditional state and remain almost entirely non-Muslim. Although Africans had extracted tin and iron from river and stream beds on the plateau long before the arrival of Europeans, not until 1904, when the British commenced large-scale operations, did the region's immense tin deposits begin to be fully exploited. Since that time the Jos Plateau has been one of the world's major suppliers of tin. The world's largest known deposits of columbite, an ore of niobium found associated with tin, have also been exploited since the 1940s. Smaller quantities of tantalite, wolfram (tungsten), kaolin, zircon, and uranium are also mined. Lead and iron ore are found in eastern and central Plateau state. At Lafia there are coking coal deposits, and gold and silver deposits are located near the town of Shendam. The plateau's mineral wealth has attracted numerous Hausa, Igbo (Ibo), Yoruba, and European migrants in the 20th century; and the absence of the tsetse fly (the carrier of trypanosomiasis) at this elevation has also lured many Fulani herdsmen to the plateau. Almost all of the plateau is now open savanna grassland because the original forested areas have long been cleared for farming or mining. Cactus hedges grow naturally, but many have been planted around villages and compounds. Acha (a grain known as hungry rice), sorghum, and millet are the most widely cultivated staple foods; but cash crops, especially potatoes, yams, and green vegetables, are grown for the plateau's largest urban markets at Jos, Bukuru, Pankshin, and Vom. A large number of cattle on the plateau supply milk to a dairy at Vom. Goats and sheep are also raised. By the early 1980s overcultivation and overgrazing pressured some farmers to move off the plateau, but several dam and reservoir projects were constructed to foster land reclamation.