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.
Boai County is located at the southern foot of Taihang Mountain, northwest of Jiaozuo City, and adjacent to Zezhou County of Jincheng City in the north. It is bordered by Jiaozuo City in the east, Wuyi County and Xiuwu County in the east, Qinyang City in the west and Geqin River in Wenxian County in the south. Boai County has jurisdiction over Qinghua Town Street Office and Hongchang Street Office, Xuliang Town, Yueshan Town, Baishan Town, Motou Town, Xiaojing Town, Jincheng Town and Zhaihuo Township, with a total area of 435 square kilometers, with an area of about 300000 mu of arable land and a population of 436000 people. In 2018, the county's GDP increased by 8.2%, the added value of the tertiary industry increased by 7.5%, and the total retail sales of consumer goods increased by 11.5%. In March 2019, it was selected into the list of the first batch of revolutionary cultural relics protection and utilization districts and counties. The second batch of national agricultural products quality and safety counties. The seventh batch of national unity and progress