OVERVIEW OF THE GEOTHERMAL-FIELD OF SLOVENIA IN THE AREA BETWEEN THE ALPS, THE DINARIDES AND THE PANNONIAN BASIN

An updated review of the available geothermal data for Slovenia is pre sented. In order to evaluate the main tectono-thermal characteristics, an overview of three most relevant geophysical parameters, namely hea t flow density, the distribution of shallow seismicity, and the depth of the Mohorovicic boundary, over a much larger, so-called Circum-Adri atic region, extending from the Tyrrhenian Sea to the Pannonian basin, is first given. The pattern and values of these parameters in the Adr iatic Sea and just outside this area differ significantly from those o f the outlying environment, and thus correspond roughly to the area kn own as the Adriatic microplate. Slovenia is situated at the northern r im of this geophysically diversified region. In the western part of th e country, where the Dinarides and Southern Alps are situated, a good correlation has been found between the deeply lying Mohorovicic discon tinuity, the low heat flow density, low temperatures at depth and a la rge negative Bouguer anomaly, whereas in the eastern part of Slovenia (the Pannonian basin) the rising mantle-crust boundary is associated w ith the high heat flow density, high temperatures at depth and a posit ive Bouguer anomaly. At the transition zone between the Southern Alps and the Dinarides, along the area of changing crustal thickness, a sha llow seismicity belt is indicated. The only DSS profile in Slovenia, c rossing the country in a SW-NE direction from Pula (Croatia) to Maribo r, reflects the tectonic relations and seismicity between the Dinaride s and the Pannonian basin.