LGRB-BW HK50: Hydrogeological units

The distribution of hydrogeological units (including cohesive top layers) on the Earth’s surface is shown. A hydrogeological unit is a rock body that, due to its petrography, texture or structure, has uniform hydrogeological properties within a defined range. A top layer is a near-surface hydrogeological unit above the first contiguous groundwater body, which does not contain any significant groundwater in its entirety, with the exception of floating groundwater. It is completely in the area of the unsaturated zone. The bandwidth within which a rock body is considered homogeneous is strongly dependent on the processing and representation scale (Ad-Hoc-AG Hydrogeology). The basic hydrogeological map is derived from the basic digital geological data set. For the determination of the hydrogeological units, the geological mapping units are divided according to hydrogeological aspects (lithofazies, hydrogeological and geochemical properties).