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a mountain system in Mongolia and China, extending from northwest to southeast for approximately 1,000 km. It is from 300 km (in the northwest) to 150 km (in the southeast) wide and has elevations to 4,362 m (Munkh- Khairkhan-Ula). The Mongolian Altai consists of several parallel ranges separated by longitudinal tectonic valleys. The peaks are primarily in the form of plateaus; near the crest are mostly corrie and hanging glaciers (the largest is Potanina Glacier). The mountains are composed primarily of Paleozoic schists, porphyries, porphyrites, and granites. The southwestern slopes are more humid than the northeastern slopes; as a result forests and meadows grow on the former (predominantly fir and larch), with steppes at lower elevations and alpine meadows at higher ones. Steppes and semideserts predominate on the northeastern slopes, with semideserts in the intermontane depressions.