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.
Qichun County is located in the southeast of Hubei Province, north of the middle reaches of the Yangtze River, belonging to Huanggang City, is an important part of Wuhan city circle, is a famous "professor county", famous for a large number of talents. The area is 2397.6 square kilometers. The total population is 1.1 million (2016). Relying on the Dabie Mountains in the north and the Yangtze River in the south, it has beautiful scenery, pleasant scenery, mild climate and four distinct seasons. Qichun County is located in the center of China's "Middle Triangle" and belongs to the "one-hour city circle" with large and medium-sized cities such as Wuhan, Nanchang and Hefei. The Beijing-Kowloon Railway, the Shanghai-Rong Expressway, the Golden Waterway of the Yangtze River and the hinterland of the Dabie Mountains run through the whole territory. Traffic extends in all directions and is very convenient. Qichun Railway Station, located at the midpoint of Beijing-Kowloon Railway, is the only urban railway station in Fujiu section. Qichun County is the hometown of Li Shizhen, a world cultural celebrity medical saint.