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.
Cangzhou, a prefecture-level city in Hebei Province, is located in the Heilonggang Basin in the southeast of Hebei Province and in the east of Hebei Plain, between latitude 37 °29-38 °57 north and longitude 115 °42-117 °50 'east. It is bordered by the Bohai Sea in the east, Tianjin and Langfang in the north, Baoding and Hengshui in the west and southwest, and Nangezhang Weixin River opposite Binzhou and Dezhou in Shandong Province. Cangzhou gets its name because of its proximity to the Bohai Sea, 120 kilometers north of Tianjin, 240 kilometers from Beijing and 220 kilometers southwest of Shijiazhuang, the provincial capital. Cangzhou has jurisdiction over 2 municipal districts, 4 county-level cities, 10 counties and Cangzhou Bohai New area, Cangzhou Economic Development Zone, Cangzhou High-tech Industrial Development Zone, with a total area of 14000 square kilometers. In 2018, Cangzhou achieved GDP 3.