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.
Weinan, a prefecture-level city under the jurisdiction of Shaanxi Province, is located in the eastern part of Guanzhong Plain and eastern Shaanxi Province. The topography takes the Weihe River as the axis, forming five geomorphological types of the north and south mountains, the two tableland and the central Pingchuan, which belongs to the warm temperate semi-humid semi-arid monsoon climate. The city has a total area of 13030 square kilometers and has jurisdiction over 2 districts, 2 county-level cities and 7 counties. In 2017, the permanent population is 5.3829 million. The Yellow River in the south and east of Weinan is adjacent to Yuncheng of Shanxi and Sanmenxia of Henan, Xi'an and Xianyang to the west, Qinling to the south and Shangluo to the south, and Qiaoshan to the north to Yan'an and Tongchuan. It is 60 kilometers away from the ancient city of Xi'an and 80 kilometers away from Xianyang International Airport. Two high-speed railways from Zhengxi and Daxi meet at this station. Six railways, including Longhai and Southwest, are vertical and horizontal with three expressways, including Lianhuo, Jingkun, and nine national highways and provincial highways.