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.
Keyouzhong Banner is located in the southern foot of Daxing'an Mountains and the northern end of Horqin Sandy Land. It is the southernmost flag of Xingan and the only animal husbandry flag of Xingan. It is adjacent to Keyouqian Banner and Tu Quan County in the north, Tongyu County and Taonan City in Jilin Province to the east, Kezuozhong Banner in the south, and Zhalut Banner, Huolingole City and Dongwuzhumuqin Banner in the west. The territory is long and narrow, with 310km from north to south and 55km from east to west, with a total land area of 15613 square kilometers (about 23.42 million mu). The main rivers that flow through Keerqin right-wing middle flag are Huolingol River, the process is 358km, and the basin area is 14113 square kilometers. the native products of Keerqin right-wing middle flag are Reed, hairy gloves and apricot stone. There are 922000 mu of cultivated land, and the main crops are sorghum, millet, corn and rice. Worker