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.
Guanling Buyi and Miao Autonomous County, located in the middle of Guizhou Province, belonging to Anshun City, is located in the slope zone inclined to the hills of Guangxi on the south side of the ridge slope in the eastern part of the Yunnan-Guizhou Plateau. The northeast and northwest are adjacent to Zhenning Autonomous County and Liuzhi Special Zone, while the southwest is bounded by Beipanjiang and Qinglong, Xingren and Zhenfeng counties. The total area is 1468 square kilometers, and the total population of the county is 323092 (2013), of which 197571 are ethnic minorities. There are 22 ethnic groups living in Buyi, Miao, Han, Gelo, Yi and so on. The county people's government is stationed in Guansuo town. In Guanling County, there is the highest bridge in China, the Baling River Bridge, the national agricultural tourism demonstration site Mucheng River rural tourism area, and the Huajiang Grand Canyon Scenic spot known as the fissure of the earth. In 2013, students were born in Guanling Buyi and Miao Autonomous County.