A CONCEPTUAL FRAMEWORK FOR MODELING THE WEST GEDAREF SANDSTONE AQUIFER

In this paper a model concept is set up for the simulation of the aquifer system in the over-pumped well fields west of the Gedaref city. Assumptions are made on different system elements that would ultimately be confirmed by numerical simulation. Prior estimates of system parameters as well as calibration targets are established to measure confidence on the model results. A typical modeling process starts with data integration and description of the hydrogeological setup, then the definition of the conceptual framework for analysis, and finally comes the numerical approximation. The conceptual framework represents an important phase in defining the quantitative framework within which a numerical scheme works. It identifies and specifies the different steps, which can be taken in the process of formulating, analysis, evaluating and presenting alternative models (KOUDSTAAL, 1992). According to SUN (1994) application of sound hydrologic reasoning during the development of an appropriate conceptual model of flow represents a full 90 % of the solution to most hydrogeologic problems.