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.
Chencang District, which belongs to Baoji City, Shaanxi Province, is located in the west of Shaanxi Province, adjacent to Tianshui City and Qingshui County of Gansu Province. Chencang District is located in the Qinling Mountains, Guanzhong Plain and the transitional area of the Loess Plateau. The geomorphology is composed of mountains, plateaus and Sichuan. It belongs to continental warm temperate monsoon climate. Many places of interest in the territory, Han Liu Bang secretly Chencang, Zhuge Kongming two felling of Qishan, Wu Fu Wu phosphorus brothers defeated Jinwu Shu and other major historical events took place here. The stone drum inscriptions unearthed in the early Tang Dynasty are the earliest stone inscriptions in China and are regarded as the ancestor of Chinese stone carvings; the White Plate and Sanshi Plate unearthed in the Qing Dynasty, as well as "he Zun" and "Wang Yogai" unearthed after the founding of the people's Republic of China provide rare material materials for the study of the history and culture of the Western Zhou Dynasty. In 2018, Chencang District had jurisdiction over 3 streets and 15.