Seismic Hazard Assessment from historical and instrumental earthquaKE catalogs for low- and middle-income countries

[Cod. UCRAN20089 SHAKE]

How could we speed up the energetic transition to mitigate climate change and reduce the dependency on  third-country hydrocarbons? The widespread deployment of renewable energies like solar and wind is occurring at an insuffient rate, hindered in part by their intermitency, as they depend on weather conditions. Geothermal energy could boost the transition towards net zero as it yields a constant energy output, providing clean, secure and affordable energy, and contributing to the Sustainable Development Goals (SDG) of the United Nations SDG7 “Affordable and Clean Energy” and SDG13 “Climate Action”. This project aims at determining the extent of geothermal resources and suitability of sites for energy production in Ukraine based on a map of local seismic hazard that will be developed from historical seismic data.

The most suitable region for geothermal exploitation in Ukraine is the coast of the Black Sea, with an estimated potential of 5-9 MW per well, but characterization and exploration are in the initial stages (Rudakov and Inkin, 2019). Site selection is of crucial importance as injection-induced earthquakes have the potential to cancel projects, as has already occurred at the enhanced geothermal systems of Basel, Switzerland, and Pohang, Korea Republic (Lee et al., 2019), and the underground gas storage at Castor, Spain (Vilarrasa et al., 2021). Determining the most suitable sites requires a full geologic and geophysical characterization and seismic hazard assessment. Yet, this assessment work has been limited due to lack of resources and, more recently, the current geopolitical conflict.

The project will have a positive impact on Ukraine by (1) cataloging the existing seismic events and their focal mechanisms and (2) inferring the seismic structure of Ukraine using records from the existing open access seismic networks in the region surrounding Ukraine. This data will then be used in combination with any available historical seismic data to develop a map of local seismic hazards within Ukraine. This map will help identify the regions of potential energy production with higher or lower seismic risk. This work will also aid in understanding the local stress field, which is crucial for planning geothermal wells using site specific knowledge to mitigate induced seismicity. Future plans monitoring and enhancing the local seismic network could also be developed using this initial data. The proposed methodology could be useful for other low- and middle-income countries with scarce permanent seismic stations.