Surface Water Interaction Modelling Using Visual MODFLOW and GIS

PHYLARESModel setup / ch.6__________________________________________________________________________________________36Figure 6. 4 Bottom elevation of layer 36.1.6 Hydrogeological informationBecause of the close relationship between the hydrological properties of groundwater reservoirsand the geological characteristics of the materials that constitute the reservoir matrix, it is helpfulto focus on the nature and compilation of geological information.The model area consists of Quaternary and Tertiary sediments forming the Quaternary andCampine aquifer system, which is confined at the bottom by the Boom clay aquitard. Table 6.3lists the geological formations, based on the hydrogeological classification system for Flanders(Cools et al. 2006). Figure 6.5 indicates the stratigraphy of the layers and figure 6.6 and figure6.7 are geologic cross- sections across transects of North – South across a line connecting themiddle points of the two opposite boundaries of the model, and a cross section along the river.The quaternary (HCOV 0100), the Pleistocene and Pliocene (HCOV 0230), and the Miocene(HCOV 0250) aquifers are mainly composed of sand. These formations are semi-permeablebecause of the heterogeneous and irregular clay deposits. The Pliocene clay layers (HCOV 0240)occur in patches. The Miocene aquifer system (HCOV 0250) is the largest of the layers. In the______________________________________________________________________________________Groundwater – Surface water interaction modeling using visual MODFLOW and GIS