Issyk-Kul Basin

a mountain basin in the Tien-Shan, in the Kirghiz SSR.

The Issyk-Kul’ Basin is rimmed by the Kungei-Alatau Range on the north (altitude up to 4,771 m) and the Terskei-Alatau Range on the south (up to 5,216 m). The bottom of the basin contains Lake Issyk-Kul’, which lies at an elevation of 1,609 m (the minimum absolute altitude of the dry floor of the basin) and has a maximum depth of 702 m. Extending almost latitudinally, the basin is 240 km long and up to 90 km wide. The basin is a syncline complicated by faults. There is much seismic activity. The bottom and the shores of Lake Issyk-Kul’ have ancient lake terraces (35–40 m high) and uplifts formed by the most recent tectonic movements. The slopes of the mountains rimming the basin have ravines; a great many rivers (more than 50) flow down the mountains to the lake. The western part of the Issyk-Kul’ Basin has an arid climate (less than 200 mm precipitation a year), with desert and semidesert landscapes. In the eastern part precipitation is up to 500 mm (up to 800 mm in the mountains), steppes predominate, and the mountainsides have forests of Schrenk spruce, with subalpine and alpine meadows higher up and glaciers and neves above 3,500 m. In the eastern part there is a coal deposit (Dzhergalan), and the southeastern part has hot mineral springs and health resorts, including Dzhety-Oguz and Aksu. The shores of Lake Issyk-Kul’ are the site of such health resorts as Cholpon-Ata and Tamga. The Issyk-Kul’ Basin is an important grain and livestock region of the Kirghiz SSR, and there are widely distributed plantings of medicinal poppy.