Re-study on the Lower Boundary of Quaternary System in the North China Plain
wang qiang 1; liu li-jun 2; xu hai-zhen 2; ma zhen 3; zhi tai-ping 4; lan zi-ting 4; wang ya-bin 5; liu xue-song 5; lin pei 6; dong dian-wei 6$$$$ (1.tianjin institute of geology & mineral resources; tianjin 300170; 2. hebei exploration institute of hydrology and engeneering geology; shijiazhuang 050021; 3. 2 nd hydrogeological team of shandong geological exploration bureau dezhou 253015; 4. 1 st hydrogeological and engeneering team of henan geological exploration bureau; xinxiang 453002; 5. tianjin bureau of geological survey; tianjin 300191; 6. beijing bureau of geological survey; beijing 100037)
..............page:52-60