Compiling the map of shallow-buried palaeochannels on the North China Plain

The 4 methods used in compiling the shallow-buried palaeochannel maps are as follows: geohydrologic, electrical-resistivity, areo electro-magnetism and drilling methods. On the North China Plain, the drilling method was used mainly accompanied by the geohydrologic and the electrical-resistivity methods. Before compiling the map, detailed studies of typical palaeochannels were undertaken of palaeochannel sediments, their ages and relation to the storage of shallow groundwater quantity and quality. This provides the theoretical foundation for compiling the map of a large area and for dividing the palaeochannels. Then, data from drilling samples were collected and each drilling hole divided into zones 1 and 2 and marked on the base map. The boundaries of zones 1 and 2 were drawn on the base map. From the map of the shallow-buried palaeochannels, we can conclude that the shallow-buried palaeochannel zones and shallow groundwater zones are identical with the sand bodies of stage I, III and IV palaeochannels.