3D Long-Term Monitoring of Recent Tectonic Activity in Demänovská Cave of Liberty

The topic of the article is the analysis of recorded data and the presentation of results from almost 24 years of monitoring tectonic movements along a neotectonic fault within the extensive underground space of the Demänovská Cave of Liberty. Displacements and rotations at the fault were measured using a mechanical-optical 3D extensometer TM-71. The measurement results subjected to statistical analysis showed a trend in two components of the spatial motion vector – vertical (Z) and horizontal (Y), which is paralel to the strike of the fault. Recent activity along the fault reflects the action of the contemporary stress field and also seismic activity within the Western Carpathians. The study also examines the relationship between the movements recorded by TM-71 and seismic events in the wider vicinity of the cave. Although long-term measurements show a significant trend of movement along the fault, its magnitude is minimal. From the perspective of cave safety, the detected neotectonic activity does not pose any risk.