Land and Resources, Natural Regions
Elburz Mountains, Mount Damavand, Dasht-e Lut, Dasht-e Kavir, Elburz
Iranís interior plateaus are almost completely surrounded by mountains. The main mountain system, the Zagros Mountains, cuts across the country for more than 1,600 km (1,000 mi) from northwest to southeast. With the exception of the Khuzestan coastal plain, which extends from the northern reaches of the Persian Gulf, the Zagros Mountains occupy all of western Iran. The central part of the range averages more than 340 km (210 mi) in width. Many peaks of the Zagros exceed 4,000 m (12,000 ft) in elevation; the highest is Zard Kuh (4,547 m/14,918 ft). Peaks rising above 2,300 m (7,500 ft) capture considerable moisture, which percolates down to the lower-lying basins as groundwater. These basins, ranging from about 1,200 to 1,500 m (4,000 to 5,000 ft) in elevation, contain fertile soil that traditionally has sustained diverse and intensive crop cultivation.
In Iranís northern reaches, a steep, narrow mountain range, the Elburz Mountains, rims the entire southern coast of the Caspian Sea. This range extends more than 600 km (400 mi) in length and averages about 100 km (about 60 mi) in width. The country's highest peak, Mount Damavand (5,670 m/18,602 ft), lies in the central part of the range. Several other peaks of the Elburz Mountains exceed 3,600 m (12,000 ft). The northern slopes of the range receive considerable rainfall throughout the year and support forests. A fertile coastal plain averaging 24 km (15 mi) in width lies between the Caspian Sea and the mountains. East of the Elburz Mountains is a series of parallel mountain ranges with elevations of 2,400 to 2,700 m (8,000 to 9,000 ft). These ranges are interspersed with many narrow, arable valleys. Several low mountain ridges, generally referred to as the eastern highlands, run along Iranís eastern border.
Within this mountainous rim lies a series of basins known collectively as the central plateau. They include the Dasht-e Kavir, a huge salt-encrusted desert in north central Iran; the Dasht-e Lut, a sand-and-pebble desert in the southeast; and several fertile oases.
The mountains of Iran constitute an active earthquake zone, and numerous minor earthquakes occur each year. Major earthquakes causing great loss of life and property damage also occur periodically. During the 18th century earthquakes twice leveled Tabriz, the principal city in the northwest, killing at least 50,000 people on each occasion. Several severe earthquakes resulting in 1,000 or more deaths occurred during the second half of the 20th century. The most devastating earthquake, centered in the fault zone where the Elburz and Zagros mountains intersect, killed an estimated 40,000 people in June 1990. Several of Iran's highest mountains are volcanic cones; only Mount Damavand and Kuh-e Taftan in southeastern Iran are active volcanoes, both periodically emitting gases near their summits.
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