3D Modeling and Geothermal Potential Assessment of a Fractured Carbonate Reservoir in the South-Eastern Pyrenees. the Empordà Case Study in NE Catalonia - GeoERA HotLime Project

Abstract

This paper presents the preliminary results of the characterization of the low enthalpy geothermal resource in the lower Tertiary fractured limestone aquifer within the Empordà Basin, located in the northeastern sector of the unthrusted foreland basin of the Pyrenees in NE Catalonia. The case study is included in the GeoERA HotLime project (co-financing H2020), which addresses the mapping and assessment of geothermal plays in deep carbonate rocks from different pilot areas in Europe. A new 3D geological and thermal model of the reservoir-bedrock system has been developed through an integrated interpretation of the previous geological, geophysical and geothermal information available in the study area, complementing it with new geophysical and rock sampling campaigns. The overall available information has been used to develop a 3D conductive layered based steady state regional heat flow model applying a heat uncertainty analysis, to infer the probable temperature distribution within the basin. The geothermal potential assessment has been addressed using the new 3DHIP-Calculator tool (ICGC-UAB, 2020), a Matlab-based software compiled for windows which allows to stochastically apply the Heat-In-Place method (Muffler and Cataldi, 1978) by using 3D voxel models. Using a geographical information system, the georeferenced output results have been converted in raster maps showing among them the spatially distributed stored heat energy (PJ/km2) under different probability scenarios (P10%, P50% and P90%). These maps allow to identify the most favorable and promising areas to go forward for the planning and development of new prospections at local scale.