Preliminary estimate of current ice thickness in the Dobšiná Ice Cave by means of geophysical and geodetic methods

Roman PAŠTEKA; Pavol ZAHOREC; Ivan ŠULEK; Erik ANDRÁSSY; Juraj PAPČO; Katarína PUKANSKÁ; Ema NOGOVÁ; Dominika GODOVÁ; Lenka ONDRÁŠOVÁ; Jozef BÓDI

doi:10.31577/congeo.2024.54.4.5

Roman PAŠTEKA Department of Engineering Geology, Hydrogeology and Applied Geophysics, Faculty of Sciences, Comenius University, Ilkovičova 6, 842 15 Bratislava, Slovak Republic https://orcid.org/0000-0001-6477-8178
Pavol ZAHOREC Earth Science Institute, Slovak Academy of Sciences, Bratislava/Banská Bystrica, Slovak Republic https://orcid.org/0000-0003-0427-6250
Ivan ŠULEK Department of Engineering Geology, Hydrogeology and Applied Geophysics, Faculty of Sciences, Comenius University, Ilkovičova 6, 842 15 Bratislava, Slovak Republic https://orcid.org/0009-0005-4786-6471
Erik ANDRÁSSY Water-Management Construction – State Enterprise, Department of Geology and Environmental Impacts, Bratislava, Slovak Republic https://orcid.org/0000-0002-0669-0597
Juraj PAPČO Department of Theoretical Geodesy and Geoinformatics, Faculty of Civil Engineering, Slovak University of Technology, Bratislava, Slovak Republic https://orcid.org/0000-0002-4124-9625
Katarína PUKANSKÁ Institute of Geodesy, Cartography and Geographical Information Systems, Faculty of Mining, Ecology, Process Control and Geotechnologies, Technical University of Košice, Slovak Republic https://orcid.org/0000-0002-7332-7691
Ema NOGOVÁ Earth Science Institute, Slovak Academy of Sciences, Bratislava/Banská Bystrica, Slovak Republic https://orcid.org/0000-0003-1578-5501
Dominika GODOVÁ Institute of Geophysics Czech Academy of Sciences, Prague, Czech Republic https://orcid.org/0000-0002-7811-2825
Lenka ONDRÁŠOVÁ Earth Science Institute, Slovak Academy of Sciences, Bratislava/Banská Bystrica, Slovak Republic https://orcid.org/0000-0001-7183-4107
Jozef BÓDI Earth Science Institute, Slovak Academy of Sciences, Bratislava/Banská Bystrica, Slovak Republic https://orcid.org/0000-0001-9653-1487

DOI: https://doi.org/10.31577/congeo.2024.54.4.5

Keywords: ground penetrating radar, microgravity method, migration, topographic effect

Abstract

The presented study focuses on the Dobšiná Ice Cave, which is worldwide unique from the speleological viewpoint, belonging to the most famous caves in Europe. During the 20th century, the research of the cave was carried out within various scientific branches. In the last years, one important part of the survey is the geodetic monitoring of the ice surface by modern laser scanning methods. Since 2020, also geophysical (georadar and microgravity) research is conducted in the Dobšiná Ice Cave. In this contribution, we present preliminary results on the present ice filling thickness, based on the interpretation of vertical radargrams and 2.5D density modelling of anomalous gravity data. Maximum thickness values from georadar measurements are more than 24.5 m in the eastern part of the cave, in the lower part of the Great Hall. Roughly estimated error of the depth determination from GPR vertical sections is at the level of ±0.5 m. Results from gravimetry apparently point to the fact that the sections with largest ice thickness could be placed rather westward to the central part of the cave. This interpretation remains questionable though, still open due to missing GPR results in the central part of the cave. We hope that future additional data and 3D density modelling will help to resolve this issue.