Abstract: The east Tianshan Mountains is located in the southern marginal zone of the Turpan-Hami Basin, Xinjiang. It is characterized by less precipitation and violent evaporation here, the annual precipitation varies in a range of 60～100 mm in the mountainous regions and 20～60 mm in the plains, but the evaporation is as high as 2, 600～3, 500 mm, and the aridity index is over 100.Some copper and copper-nickel mines have been found in the east Tianshan Mountains since recent years, and this region is hoped to be as the production base of the copper, nickel, iron and gold minerals. Water supply, however, is the main restricting factor for the mineral development. In this paper, the water-bearing mechanism of the structures in the east Tianshan Mountains is researched, and the types of water-bearing structures and their significance for looking for groundwater are analyzed. The results show that the water-bearing properties, groundwater distribution and enrichment of the structures are mainly controlled by the geologic formations, and the various water-bearing structures dissected and closed by the geologic formations are the main strata for looking for groundwater.

Key words: water-bearing structure, geologic formation, water supply, the east Tianshan Mountains