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.
Xiangqiao District, which belongs to Chaozhou City, Guangdong Province, is the central city of Chaozhou City. It is located in the middle and lower reaches of Hanjiang River. It is named after Xiangzi Bridge, one of the four ancient bridges in China, with a total area of 325.35 square kilometers. Xiangqiao District is a subtropical marine monsoon climate with abundant rainfall, mild climate, long summer and short winter, and sufficient sunshine. As of 2018, Xiangqiao District has jurisdiction over 9 streets and 4 towns, and the district government is stationed in Fengxin Street. By the end of 2018, Xiangqiao District had a resident population of 552000. Xiangqiao District of Chaozhou City was established in December 1991. On June 28, 2013, with the approval of the State Council of the people's Republic of China, the three towns of Phosphate Creek Town, Guantang Town and Tiepu Town in Chaoan County were placed under the jurisdiction of Xiangqiao District of Chaozhou City. Xiangqiao District is the core area of tide culture and the famous historical and cultural city of the country.