In North China, karst features occur mainly in Hebei, Shanxi, South Liaoning, northern parts of Shandong and Henan, and Shanxi Provinces, extending to the north of the line from the Qingling mountain range to the Huaihe River. The terrain belongs to a semi-arid and semi-humid warm temperate zone. Karst is not well developed on the land surface, whereas underground is mostly developed in the forms of fissures and pores. The main water-bearing formations are Mid-Ordovician limestones, with copious groundwater...