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.
Huili County, known as Huiwu and Huichuan in ancient times, belongs to Liangshan Yi Autonomous Prefecture of Sichuan Province. Huili County is located in the southernmost tip of Sichuan Province, located in the heart of Panxi. The county covers an area of 4527 square kilometers and has jurisdiction over 2 streets, 14 towns and 11 townships, with a permanent population of 426000 at the end of 2018. There are 29 ethnic groups in the county, including Han, Yi, Tibetan, Hui and Dai, with ethnic minorities accounting for 16.7% of the total population. Huili, founded in the sixth year of the Yuan Dynasty (111 BC) in the Western Han Dynasty, is a famous historical and cultural city of the country. The ancient city culture, red culture, pomegranate culture and Sichuan-Yunnan culture are integrated to form a continuous line of Huili culture. Huili is rich in resources, rich in mineral resources, land resources, light and heat resources and tourism resources, known as "Panxi treasure basin"