New Research Perspectives in Light of Dense Cross-Border Experiments in West Bohemia and Vogtland Regions

Abstract

The Eger Large-N International Seismic Experiment (ELISE) is a major cross-border project deploying a temporary network of over 300 broadband and short-period seismic stations in the West Bohemia/Vogtland region, located at the border of Czechia and Germany. This experiment offers new research opportunities in one of the most seismically and geodynamically active intraplate regions in Europe, characterized by recurrent earthquake swarms resulting from magmatic crustal fluids and mantle CO₂ degassing processes. The collision and thrusting of Variscan tectonic domains have created a unique natural laboratory to investigate how ancient structures influence present-day magmatic processes and fluid–rock interactions. ELISE aims to address fundamental questions regarding the origin of swarms, their dynamics, and hazard potential, as well as their relationship with geodynamic activities in the region. The stations of this dense array have been operating since August 2025 and will record for up to 18 months. They will enable high-resolution imaging of crustal structures through the use of high-resolution earthquake locations, ambient noise tomography, receiver function analyses, and local earthquake tomography. Based on previous experience, we hypothesize that intensifying seismic networks will reveal at least ten times more local earthquakes, ultimately clarifying the mechanisms of swarm earthquakes by constraining fluid migration paths and structural and geological boundary conditions. Better earthquake locations, together with high-resolution subsurface models of different quantities, will provide new insights into the interaction between tectonic and fluid-induced seismicity revealing the possible role of carbonate brines and melts in the formation of swarms. This will improve our understanding of geodynamic and fluid-magma interactions in intraplate tectonic settings. This paper provides an overview of the ongoing ELISE experiment. It outlines its goals, scientific framework, and expected contributions.