Geothermal potential in the Croatian Part of Pannonian Basin: mapping geothermal plays

The Croatian part of the Pannonian Basin System (CPBS) represents the southwestern margin of the Pannonian Basin, characterized by a high geothermal gradient (4.9°C/100 m). There is a rich tradition of using geothermal aquifers for balneological, recreational and medicinal purposes. The estimation of geothermal potential is crucial at a time when Europe is increasingly turning to renewable energy sources. There are three main geothermal plays in the CPBS: pre-rift, syn-rift and post-rift play. Temperature maps were created for each geothermal play. Temperature measurements in a total of 75 wells were used as input data. A correlation between depth and temperature was established and the assumption that the highest temperatures are to be expected in the deepest parts of the basins for all three geothermal plays was confirmed. Temperature maps of the pre-rift, syn-rift and post-rift geothermal plays were created by applying the depth-temperature functions on the depth maps. The highest temperatures of the pre-rift, syn-rift and post-rift plays are expected in the deepest parts of the Drava and Sava basins.