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.
Kuitun, founded in 1975, is a county-level city directly under the Kazakh Autonomous Prefecture of Yili, Xinjiang Uygur Autonomous region. It is located in the middle part of the northern foot of Tianshan Mountain, southwest of Junggar Basin, bordering Shawan County in Tacheng area in the east, Wusu City in Tacheng area in the west, Karamay District in the north and Dushanzi District in Karamay City in the south. The administrative district covers an area of 1109.89 square kilometers and has jurisdiction over five streets and one agricultural township. The city name means "cold" in Heshuote Mongolian. Kuitun is a new industrial and commercial city in northwest China. At the end of 2016, the total number of urban households was 60, 000, with a total population of 158700, an increase of 1100 over the previous year. Kuitun's economy is the main agricultural and pastoral area and grain, oil and cotton base in Xinjiang. The second Eurasian Continental Bridge runs through Kuitun. 2018