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.
Zhuoni County is located in the eastern part of the Qinghai-Tibet Plateau. Zhuoni County is located in Gansu Province and the southeast of Gannan Tibetan Autonomous Prefecture, between 102 °40 degrees east longitude and 104 °02 east longitude and 34 °10 degrees north latitude. The total area is 5419.68 square kilometers. By the year 2000, it had jurisdiction over 1 town, 15 townships and 1 nationality township. Zhuoni County, with an average annual temperature of 4.6 degrees Celsius, is a plateau continental climate, cold and humid, the four seasons unknown. In 2012, Zhuoni County achieved a regional GDP of 1.068 billion yuan, an increase of 14.2% over 2011, and a large-caliber fiscal revenue of 124 million yuan, an increase of 11.84% over 2011. 2014. Zhuoni County achieved industrial added value of 125.95 million yuan in the first half of the year. The specialty of Zhuoni County is Tao inkstone and sheep.