a mountain system in northeastern Iran—in the ostan of Khorasan—and the southern Turkmen SSR.
The Turkmeno-Khorasan Mountains lie between the Elburz Mountains to the west and the Paropamisus Mountains to the east. The system is more than 600 km long and has a maximum width of 250 km. Elevations range from 1,500 to 2,000 m, with a maximum elevation of 3,314 m (Mount Kangzushk in the Binalud Range). A longitudinal band of valleys and basins formed by the Atrek and Kashafrud rivers divides the Turkmeno-Khorasan Mountains into the Kopetdag Mountains to the north and the Ni-shapur Mountains to the south.
The Turkmeno-Khorasan Mountains, a system of arcuate, folded-block structures, form the northern margin of the Alpide geosynclinal region. From south to north these structures are the Aladagh-Binalud meganticlinorium, the Quchan-Meshed superimposed trough of the Pliocene and Anthropogenic system, and the Kopetdag meganticlinorium. The pre-Alpide basement is formed of geosynclinal pre-Cambrian metamorphic rocks, subcratonic Paleozoic formations, and extrusive and sedimentary Upper Paleozoic-Triassic formations. The Alpide complex is formed of Jurassic, Cretaceous, and Paleogene geosynclinal formations and orogenetic formations of the Upper Oligocene and Anthropogenic system. The mountains have a high level of seismicity. Useful minerals include anthracite, complex metallic ores, and building materials. The foothills of the Turkmeno-Khorosan Mountains contain the Iranian natural gas deposit of Hangiran.
S. P. VAL’BE and IU. K. EFREMOV