Polish geothermal resources are classified as low enthalpy. However, higher 
temperatures are expected in the younger Paleozoic Platform characterized by 
60-90 mW/m2 Heat Flow (HF). It is decreasing in North Eastern Poland reaching 
40-50 mW/m2 at the old Precambrian craton.  
The Paleozoic Platform (28-34 km thick) and up to 10 km thick sedimentary 
cover (Guterch i Grad, 1996) is accompanied by increased HF, elevated mantle 
HF, and thin thermal lithosphere of less than 100 km (Majorowicz, 2005). High 
HF anomaly axis agrees with the Dolsk Fault course and the Variscides extent. 
The Variscan Front lines up with increased surface gradient of HF. Rapid HF 
decline correlates with Trans European Suture Zone and it is explicitly seen at 
temperature cross sections below 1.5 – 2 km. The temperatures of the upper 
part (less than 1.5-2 km) may be influenced by long surface temperature 
changes (Gorbachev, 1995; Szewczyk and Giętka, 2003; Wróblewska and 
Majorowicz, 2006). The temperature pattern at 1 and 2 km depth does not 
reflect tectonic structure but a general division between the platforms 
(Precambrian-cold vs. Paleozoic-warm). Deeper temperature patterns from -4 
km(max. T 150 oC) and -5 km (max. T 175 oC) are in good correlation with the 
course of the Variscides Front Zone occurence. 

References:
Gorbachev Y.I., 1995, Well logging. Fundamentals of methods. Chichester, NY, 
Brisbane, Toronto, Singapore. J. Willey.
Guterch, A., Grad, M., 1996. Seismic structure of the Earth’s crust between 
Precambrian and Variscan Europe in Poland. Publs. Inst. Geophys. Pol. Acad. 
Sc., M-18 (273), 67-73.
Majorowicz J., 2004. Thermal lithosphere across the Trans-European Suture 
Zone in Poland. Geological Quaterly v.48, no.1 : 1-14
Szewczyk, J. and Gientka D., 2003, Climate and climatic change from 
underground temperatures: Continental energy balance, land  - surface 
processes, integration with meteorological and proxy data, EGS/AGU  2003 
abstract CL19 and poster, EGS/AGU 2003, April, Nice, France 
Wróblewska M., Majorowicz J., 2006. Thermal lithosphere model of central and 
north – west Poland. Prace PIG 188: 69-76

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