Assessing Geothermal Energy Production Potential: Screening Cambrian Geothermal Complexes in Lithuania

Lithuania’s southwestern region holds a geothermal anomaly with two key complexes: Parnu–Kemeri, featuring Devonian sandstone hydrothermal reservoirs with excellent flow properties (26% porosity, 2000 mD permeability) but limited temperatures (up to 45°C); and Cambrian sandstone reservoirs, offering higher temperatures (up to 96°C) but weaker petrophysical attributes (7–15% porosity, permeability <45 mD).

A study aims to assess geothermal potential for commercial use by initially conducting geological screening of sites within Cambrian sandstone aquifers and depleted hydrocarbon reservoirs. This involves analyzing petrophysical properties, well placement, and static/dynamic parameters (pressure, temperature). Promising sites are identified based on these parameters. Further, detailed numerical modeling utilizes advanced Multiphysics numerical models, constructing high-resolution 3D reservoir models using real data from Cambrian aquifers and abandoned hydrocarbon reservoirs.

The study culminates in identifying the top three sites with high potential. These sites undergo additional analysis, including uncertainty modeling of dynamic/static parameters. Probabilistic forecasting estimates geothermal energy production potential for the selected sites. This study establishes a benchmark for assessing sustainable geothermal energy potential in similar reservoirs across Lithuania, Latvia, Kaliningrad, and Poland.