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.
Xiaogan got its name from Dong Yong, the filial son of the Eastern Han Dynasty, who buried his father and felt heaven and earth for filial piety. Xiaogan is a regional central city in Hubei Province, an important member of Wuhan urban agglomeration and the urban agglomeration in the middle reaches of the Yangtze River. It is also one of the most potential and competitive cities in central China, and its comprehensive competitiveness ranks among the top six in Hubei Province. Xiaogan is located in the northeast of Hubei Province, north of the Yangtze River and east of the Han River, bordering Wuhan, the capital of Hubei Province, about 60 kilometers away from the center of Wuhan and only 30 kilometers away from Wuhan Tianhe International Airport. Now under the jurisdiction of Xiaonan District, Yunmeng, Dawu,.