A mesa is an isolated, flat-topped elevation, ridge or hill, which is bounded from all sides by steep escarpments and stands distinctly above a surrounding plain. Mesas characteristically consist of flat-lying soft sedimentary rocks capped by a more resistant layer or layers of harder rock, e.g. shales overlain by sandstones. The resistant layer acts as a caprock that forms the flat summit of a mesa. The caprock can consist of either sedimentary rocks such as sandstone and limestone; dissected lava flows; or a deeply eroded duricrust. Unlike plateau, whose usage does not imply horizontal layers of bedrock, e.g. Tibetan Plateau, the term mesa applies exclusively to the landforms built of flat-lying strata. Instead, flat-topped plateaus are specifically known as tablelands.
Manas County, which belongs to Changji Hui Autonomous Prefecture of Xinjiang Uygur Autonomous region, is located in the hinterland of Xinjiang and stands in a triangle with Tacheng in the north and Yining in the west. It is known as the "west gate" of Urumqi. It is 126 kilometers east from Urumqi, the capital of Xinjiang, and 91 kilometers away from Changji City, where the government of Changji Prefecture is located. Lanxin Railway, G30 National Expressway runs through the county, the second and third supercharged transmission stations of "West-to-East Gas Transmission" and the first station of "West-to-East Power Transmission" 750kV Phoenix Station are all located in Manas County. As of 2013, Manas County has a total area of 11000 square kilometers and has jurisdiction over 14 township stations and 5 county tour farms. Manas County has 32 ethnic groups, including Han, Hui, Kazak and Uygur, with a total population of 280000, including 82.33% of Han nationality, 3.85% of Hui nationality and 10.59% of Kazak nationality.