一、出乎意料的北方岩溶地面塌陷中国北方,相当北纬33°-42°、东经108°-126°。西起晋陕黄土高原,东濒渤海,北接燕山及长白山,南部秦岭、伏牛山至淮河以北一线:包括冀、晋、鲁中南、豫西、渭北东部、徐淮及京、津、唐等重要经济区的范围内,石灰岩地层广布,占上述地区面积的59.4%。 First, the unexpected collapse of the northern karst surface in northern China, equivalent latitude 33 ° -42 °, longitude 108 ° -126 °. West of the Jin-Shan Loess Plateau, east of the Bohai Sea, north of Yanshan and Changbai Mountain, southern Qinling, Funiu Mountain to the north of the Huaihe River: including Hebei, Shanxi, Shandong and South Africa, western Henan, eastern Weibei, Xuhuai and Beijing, Tianjin, Tang and other important economic zones within the limestone strata, covering 59.4% of the area.