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.
Gonghe County is one of the five counties in Hainan Tibetan Autonomous Prefecture of Qinghai Province. it is a county with large population, vast territory and large proportion of animal husbandry economy in Qinghai Tibetan area. it plays an important role in the economic and social development layout of Qinghai Tibetan area. Located in the northeast of Qinghai Province, it is the Dongmen household of the Qinghai-Tibet Plateau, known as the "throat of Qinghai-Tibet". It is bounded by Qinghai Lake in the north, the "Mother River" in the south, the Yellow River in the east, Riyue Mountain in the east and the agricultural area in the east, and adjoins Qinghai's southern Tibetan area in the west. Gonghe County has jurisdiction over 11 townships, 99 administrative villages and 14 community neighborhood committees, with a total area of 17300 square kilometers. as of 2012, the total population was more than 134000, including 22 ethnic minorities, including Tibetan, Han, Hui, Sala and Mongolians. among them, ethnic minorities account for 70% of the total population of the county, and there are available grasslands.