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.
Xiangcheng, located in the southeast of Henan Province, Zhoukou City under the jurisdiction of county-level cities, located in the south of the Yellow River alluvial plain, the main tributary of the Huaihe River in the middle reaches of the Shaying River. Located at the junction of Henan and Anhui provinces, Da-Guang Expressway and Ningluo Expressway meet in the urban area, 106 National Highway and 5 provincial highways cross the whole territory, Luofu Railway connects Jingguang and Jingjiu, and Shaying River shipping runs directly to the Yangtze River. it is a better meeting point of people flow, material flow, capital flow and information flow in southeast Henan. In 2018, the city's GDP reached 33.991 billion yuan, an increase of 8.7% over the same period last year. Xiangcheng's industrial system, which is supported by monosodium glutamate, leather, medicine and textile, is the largest handmade shoe production base in China, the location of China's famous lotus monosodium glutamate, and the nearest waterway city in the central and western regions to the Yangtze River Delta. In 2011, he won the "Best Investment City in China" and "medium".