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.
Yanling County, which belongs to Xuchang City, Henan Province, is located in the middle of Henan Province, to the east of Qianli Funiu Mountains and to the south of the Yellow River. It is bordered by Changge City and Jian'an District in the west, Kaifeng City in the north, Zhoukou City in the east and Luohe City in the south. It now has jurisdiction over 12 towns and 386 administrative villages (communities) with a total population of 667000 people and a total area of 866 square kilometers (996000 mu of arable land). In recent years, Yanling County has adhered to the overall layout of "five in one" and the strategic layout of "four comprehensive", adhered to the concept of innovative, coordinated, green, open and shared development, and made great efforts to build ecological mausoleum, prosperous mausoleum, civilized mausoleum and happy mausoleum. Solid steps have been made in the journey of building a well-off society in an all-round way. Yanling County is located in the core area of the Central Plains highway network, adjacent to Zhengzhou Airport Economic Comprehensive Experimental Zone, north to the new.