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.
Dongliao County is located in the central and southern part of Jilin Province. Dongliao River originated in the territory and got its name from the river. It covers an area of 2186 square kilometers and has jurisdiction over 13 townships and 233 administrative villages with a total population of 360000. It is the first batch of national ecological construction demonstration areas, national commodity grain base, national one million mu artificial forest advanced county, national resource-based city succession alternative industry special support county, national cultural construction advanced county, the hometown of Chinese folk culture and art (Manchu paper-cut), the hometown of Chinese Errenzhuan art. Dongliao County is an emerging county with relatively developed modern agriculture, circular economy and automobile equipment manufacturing. In 2013, Dongliao County achieved a GDP of 2.01991 billion yuan, an increase of 23.6% over the same period in 2012 at comparable prices, of which the primary, secondary and tertiary industries were realized.