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.
Suiyang District is the municipal district of Shangqiu City, Henan Province, which is located in the south of Shangqiu City, Liangyuan Park in the north, Shangqiu New area and Yucheng County in the east, Ningling County in the west, Zhecheng County, Luyi County and Qiaocheng District, Bozhou City, Anhui Province. It is the seat of Shangqiu Municipal Party Committee and Municipal Government, and the political, economic, cultural and tourism service center of Shangqiu City. By the end of 2017, the region had jurisdiction over 19 streets (towns), with a total area of 890 square kilometers and a resident population of 710000 (excluding Shangqiu New area). Suiyang District is an important birthplace of Chinese civilization. Li Ren, the head of the three emperors, invented drilling wood to make fire here, and Suiyang is known as "the hometown of Chinese fire culture". The Shang people, merchants and the Shang Dynasty originated here, and Suiyang is known as "the hometown of Chinese business culture". Suiyang District is the Xia Dynasty, Shang Dynasty, Zhou Dynasty and Song Dynasty, Han Dynasty Liang State, Wei and Jin dynasties