Lithosphere Thickness from New Heat-Flow Data of the Odra Variscan Area, S-W Poland

Equilibrium temperature data from shafts in a mining area of SW Poland in the Paleozoic Platform were used for heat-flow calculations. A new technique to calculate paleoclimatic correction for heat-flow determination from single deep temperature data and equilibrium surface temperatures was applied. Elevated surface heat flow of 82–87 mW m −2 and mantle heat flow of some 37–41 mW m −2 were found. This high heat-flow zone spreads from S-W Poland, in the Variscan deformation front, towards the German part of the Polish-German basin. Calculations of geotherms for a variety of heat production models of the crust and upper mantle point to lithosphere–asthenosphere boundary depths of about 80–90 km compared to seismologically determined depths of 90–120 km.