HCOV_0100, basis of the Quaternary Aquifer Systems

Flanders is made up of an alternation of aquifers (sand, gravel, chalk, solid rock, ...) and regionally occurring non-aquifers (e.g. clay). The sequence of these aquifers and aquitards has its own coding in Flanders: the Hydrogeological Coding of the Subsurface of Flanders (HCOV-coding). The HCOV coding is made up of hydrogeological main, sub and base units. The main unit groups a sequence of geological layers that have broadly the same hydrogeological properties and thus form a single whole. HCOV_0100 (Quartar Aquifer Systems) is the collection of all hydrogeological aquifer systems of Quaternary origin, with the exception of some Quaternary deposits in the Kempen. These are isolated, highly fragmented and heterogeneous aquifers formed by the Quaternary top layers. It is a bundle of various hydrogeologically independent aquifer systems, usually of limited size. This main unit is rather a main administrative unit. The dataset ‘HCOV_0100, basis van de Quartaire Aquifersystemen’ shows in a grid per grid cell the altitude value (in m TAW) of the lower limit of this hydrogeological layer.