Pilot area activities – #14 Assessment of shallow geothermal energy resources in Warsaw agglomeration, Poland

Measurements of thermal properties of soils and rocks and geophysical investigations

The Polish Geological Institute – National Research Institute (PIG-PIB) carried out a campaign of field investigations to assess geological and hydrogeological conditions and to measure thermal properties of rocks and soils in the urban agglomeration of Warsaw in April and May 2020. The Quaternary deposits are up to 200 metres thick and rest on Neogene and Paleogene sediments (Figures 1 and 2). Highly diverse origin of Quaternary formations results in strongly heterogeneous lithology and thermal properties of rocks and soils. Knowledge on local geological and hydrogeological conditions is crucial for use and management of low-temperature geothermal energy and application of ground source heat pumps.

In-situ measurements of thermal conductivity and resistivity, volumetric specific heat capacity and thermal diffusivity of the soils and Quaternary rocks were performed with use of KD2 Pro Thermal Properties Analyzer (Figure 3). The measurements were taken all over the city and focused on undisturbed and non-weathered outcrops. Measurements of samples of consolidated deposits such as clays will be completed at a later stage in the laboratory. The results will enable a correlation between lithological properties of the rocks and their thermal parameters and support parametrisation of the geothermal models and maps.

The geoelectric resistivity method was used to investigate geological and hydrogeological settings with special focus on the structure of the present Vistula River valley. The results will improve construction of the standard geological profile. Investigations will contribute to MUSE by improving our understanding of local geology, hydrogeology and geothermal potential. The results will be used for geological modelling and mapping of low-temperature geothermal potential and suitability for shallow geothermal energy systems.

The global COVID-19 pandemic affected implementation of field investigations in the Warsaw agglomeration area which started later than planned and need to be continued in near future (Figure 4). The MUSE team at PIG-PIB focused meanwhile on gathering and processing of additional archive data and source material (Figure 5).     

For more information about the activities in the Warsaw agglomeration pilot area, please contact:
Maciej Kłonowski, maciej.klonowski@pgi.gov.pl

Figure 1: Simplified geological map of Warsaw agglomeration and adjacent area.
Figure 2: Geological cross-section of Warsaw agglomeration.
Figure 3: In-situ field measurements of thermal properties with KD2 Pro Thermal Properties Analyzer.
Figure 4: Geophysical investigations in the Vistula River valley.
Figure 5: Scanning geological reports under strict hygienic regime at the National Geological Archive at PIG-PIB.

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