3D visualisation of groundwater composition and age: RESOURCE Deliverable 3.3

The cross-border demonstration project H3O-PLUS intends to set a new standard for harmonization across borders, not only for hydrostratigraphy, but also for hydrological data such as groundwater heads and groundwater quality. H3O-PLUS, WP3 of GeoERA RESOURCE, aims to be an advanced demonstration of a transboundary assessment of groundwater resources. It is ‘advanced’ in the sense that it builds on and extends on previous work, trying to make it more useful for groundwater policy and management and for subsurface spatial planning. A 3D hydrogeological model has been developed in a series of so called ‘H3O’ projects1 in the transboundary region around the Roer Valley Graben, comprising parts of Germany, the Netherlands and Belgium (Vernes et al. 2018). The model contains 3D maps of the top, base and thickness of aquifers and aquitards. H3O-PLUS aims to add attribute data to these maps to facilitate the use of the maps in decision making processes. Note that the project does not aim to produce new maps or spatial delineations. The objective is to characterize units on existing maps and hence support the interpretation and use of those existing maps. The overall study area coincides with the study areas of previous H3O projects (Figure 1.1). Vertically, the study is limited to the clastic (hydro)geological layers of Cenozoic age or younger. This coincides with the vertical scope of the recently developed transboundary 3D (hydro)geological models of the H3O projects. The base of the models is thus located at the top of the Chalk aquifer (Houthem, Maastricht / Kunrade Formation) or the top of the Carboniferous deposits.