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.
Hubei Province, referred to as "E" for short, is the provincial administrative region of the people's Republic of China and the capital of Wuhan. It is located in central China, bordering Anhui in the east, Chongqing in the west, Shaanxi in the northwest, Jiangxi and Hunan in the south, and Henan in the north. It lies between latitude 29 °01: 53 "- 33 °6 °47" N and longitude 108 °21 °42 "- 116 °07 °50" E. it is about 740km long from east to west and 470km wide from north to south, with a total area of 185900 square kilometers, accounting for 1.94% of the total area of China. The eastern end is Huangmei County, the western end is Lichuan City, the southernmost end is Laifeng County, and the northernmost end is Yunxi County. The topography of Hubei Province is roughly surrounded by mountains in the east, west and north, low and flat in the middle, and slightly open to the south as an incomplete basin. In the total area of the province, mountains account for 56%.