Multi-layer circulation model of groundwater flow systems on the Ordos plateau: evidence from water head measurements at different depths of a deep borehole by the Packer system

The study of groundwater flow systems and circulation models are a basis for the study of the groundwater formation mechanism and has great significance for correct understanding and assessments of groundwater resources. In the Ordos plateau, several independent groundwater flow systems with different scales and circulation depths were formed under the control of the aquifer systems and numerous groundwater discharge points. The data from water head tests at different depths by the Packer system prove that the Ordos plateau groundwater flow system is a typical “Toth model”, i.e. the regional groundwater flow system generally contains three systems: deep circulation system, intermediate circulation system and shallow system. The shallow circulation system occurs within 200 m below the surface and the deep system circulates below 400 m depth.