ELBURZ MOUNTAINS

also spelled Alborz, Albourz, Alburz, or Elburs, Persian Reshteh-ye Kuhha-ye Alborz, major mountain range in northern Iran, 560 miles (900 km) long. The range, most broadly defined, extends in an arc eastward from the frontier with Turkmenistan southwest of the Caspian Sea to the Khorasan region of northeastern Iran, southeast of the Caspian Sea, where the range merges into the Aladagh, the more southerly of the two principal ranges there. More commonly, however, the westernmost part of the range is called the Talish (Talysh, Talesh, or Tavalesh) Range, or the Bogrov Dagh; the Elburz Range, in its strictest sense, forms part of the central stretch of the chain, which also includes Iran's two highest peaks, Mount Damavand and Mount Alam. The Elburz mountain system traverses virtually all of the northernmost portions of Iran from east to west. The Elburz chain is not as truly alpine ( i.e., resembling the European Alps) in its structure as is often suggested. On the one hand, continental conditions regarding sedimentation are reflected by thick Devonian sandstones (formed 345,000,000 to 395,000,000 years ago) and by Jurassic (136,000,000- to 190,000,000-year-old) shales containing coal seams. On the other hand, marine conditions are reflected by Permo-Carboniferous (225,000,000- to 345,000,000-year-old) strata that are composed mainly of limestones, as well as by very thick beds of green volcanic tuffs and lavas. Orogenic (mountain-building) phases of importance date from the younger Tertiary (Miocene and Pliocene epochs) Period (between 2,500,000 and 26,000,000 years ago). Over large areas they produced only a loose folding; but in the Central Elburz a number of folds were formed into blocks thrust mainly southward but in places northward, with cores made of Paleozoic rocks. Structurally and topographically, the Elburz system is less clearly defined on the southern than on the Caspian (northern) side of the chain, since various off-branching elements interconnect it on the southern side with the adjoining Iranian Plateau. The Western Elburz Range runs south-southeastward for 125 miles (200 km). Varying in width from 15 to 20 miles (24 to 32 km), it consists of a single asymmetric ridge, the long slope facing the Caspian. Few of its peaks approach or exceed 10,000 feet (3,000 m) in height. There is a low pass west of Astara, near the Turkmenistan frontier, 5,000 feet (1,500 m) above sea level. The Safid River, formed by the junction of the Qezel Owzan (Qisil Uzun) and Shahrud rivers, is the only river to cross the whole width of the chain: its gorge, giving access to the low pass of Qazvin, offers the best passage through the mountain chain, although by no means an easy one, between the Gilan region on the shores of the Caspian and the inland plateau to the south. The Central Elburz is 250 miles (400 km) long. East of the longitude of Tehran, which lies to the south of the range, it reaches a width of 75 miles (120 km). Located among the longitudinal valleys and ridges of the range are some important centres of settlement, with the towns of Deylaman, Razan, Kojur, and Namar located on the Caspian side and Emamshahr (formerly Shahrud), Lar, Damavand, and Firuzkuh on the southern side. There are likewise many gorges, by which the rivers find their way down one or another of the slopes. Only two passes allow a relatively easy crossing in a single ascentthese are the Kandevan Pass, between the Karaj and the Chalus rivers, and the Gaduk Pass, between the Hableh and the Tala rivers. The main divide runs generally south of the highest crest, whichwith the exception of the towering and isolated cone of the extinct volcano Mount Damavand (18,386 feet )culminates in the glaciated massif of Takht-e Soleyman, which rises to more than 15,750 feet (4,800 m). The Eastern, or Shahkuh, Elburz runs about 185 miles (300 km) in a northeasterly direction. Since two ranges branch off on its southern side and no compensatory elements appear on the northern side, its width dwindles to less than 30 miles (48 km). With the exception of the Shahkuh Range proper (which reaches an elevation of 12,359 feet ), the chain decreases in height toward the east. Longitudinal valleys are found less and less frequently east of the Shahkuh. There are several passes at low elevations. The Caspian and the inland, or southern, slopes of the Elburz differ markedly from each other in climatic and vegetational aspects. The Caspian slope has a distinctly humid climate, thanks to northerly air movements, enriched with moisture from the sea, which collide with the steep faces of the mountains to cause precipitation. This precipitation amounts to more than 40 inches (1,000 mm) annually in the lowlands of the Gilan region and is even more plentiful at higher elevations. Although it decreases toward the east, it still suffices to nourish a humid forest for the whole length of the chain on the Caspian side, where the soils are mostly of the brown-forest type. The natural vegetation of this slope grows in distinct zones: the luxuriant Hyrcanian forest on the lowest levels; a beech forest in the middle zone; and a magnificent oak forest from the elevation of 5,500 feet (1,700 m) up to the levels where gaps in the divide allow the moist air to overflow into the inland basins. In some sheltered valleys there are extensive stands of wild cypress; sheltered valleys adjacent to the Safid River constitute the only olive-growing areas of note in Iran. The southern slope of the Elburz, by direct contrast, shares the arid character of the Iranian Plateau. Annual precipitation varies between 11 and 20 inches (280 and 500 mm) and is very irregular. The soils are mostly of the type associated with steppe (treeless, grassy, or shrubby) vegetation. The slope has become even more steppelike ever since the almost complete destruction of its original dry forest of junipers. The Hyrcanian tigers for which the Caspian forests were famous are now very rare; but other wild cats, such as the leopard and the lynx, are still numerous in the Elburz. The bear, the wild boar, red and roe deer, the mouflon (wild mountain sheep), and the ibex are also present. Eagles and pheasants are notable among birds. While large areas of the Elburz Mountains are almost uninhabitedsome being occupied only by nomads and others having been depleted by Turkmen raids in the 19th centurythere are still several well-settled districts, including Deylaman, Alamut, Talaqan, and Larijan (at the foot of Mount Damavand). The landscape of the Caspian slopes is characterized by forest clearings with shingle-roofed loghouse villages and by lush fields and pastures. The landscape of the inland slopes is of the oasis type. Extensive grain cultivation occurs on both slopes, and cattle raising occurs on the Caspian side. Alpine pastures, seasonally dotted with flocks of sheep, cover an extensive zone yet higher. The land-distribution pattern prevailing in the Elburz includes a high proportion of peasant ownership. The holdings often are much-fragmented. Many of the traditional ways of livelihood of the mountaineers, including charcoal burning (now prohibited because of devastation of the forests), the transportation of goods (especially of rice and of charcoal for Tehran) by pack animals, and the working of hundreds of small coal mines, have been displaced by the 20th-century modernization of Iran. Apart from the main line of the trans-Iranian railroad, which links Tehran with Bandar-e Torkeman via the Gaduk Pass, there are several asphalted roads across parts of the Elburz. From west to east, these run between Ardebil and Astara, between Qazvin and Rasht, between Tehran and Chalus, between Tehran and Amol (via Damavand); between Tehran and Babol (via Firuzkuh), and between Emamshahr and Gorgan (via Kotal-e Zardaneh Pass). The wild (natural or original) forests of the Elburz Mountains cover more than 8,000,000 ac (3,000,000 ha), of which some 3,000,000 ac can be exploited commercially for timber and other wood. There are also a few modern coal mines, as well as some deposits of iron and other ores. But most important is the water of the rivers, which is used for irrigation, for generating hydroelectric energy, and for supplying the fast-growing Tehran. Spectacular dams have been built. These include the Safid Rud Dam, used for the irrigation of the Safid Rud Delta; the Karaj Dam and the Jajrud Dam, used mainly for supplying water to Tehran and partly for irrigation; and a series of dams on other rivers of the Mazandaran ostan also used for irrigation. Hans Bobek Additional reading W.B. Fisher (ed.), The Land of Iran, vol. 1 of The Cambridge History of Iran (1968), with bibliography; H. Bobek, Iran: Probleme eines unterentwickelten Landes alter Kultur, 3rd ed. (1967); A. Gansser and H. Huber, Geological Observations in the Central Elburz, Iran, Schweiz. Miner. Petrogr. Mitt., 42:583630 (1962); J. Stocklin, Structural History and Tectonics of Iran: A Review, Bull. Am. Ass. Petrol. Geol., 52:12291258 (1968), with bibliography.