Imaging the structure of cave ice by ground-penetrating radar

Several caves in high elevated alpine regions host up to several meters thick ice. The age of the ice may exceed some hundreds or thousands of years. However, structure, formation and development of the ice are not fully understood and are subject to relatively recent investigation. The application...

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Bibliographic Details
Published in:The Cryosphere
Main Authors: Hausmann, H., Behm, M.
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2011
Subjects:
Online Access:https://doi.org/10.5194/tc-5-329-2011
https://noa.gwlb.de/receive/cop_mods_00027560
https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00027515/tc-5-329-2011.pdf
https://tc.copernicus.org/articles/5/329/2011/tc-5-329-2011.pdf
Description
Summary:Several caves in high elevated alpine regions host up to several meters thick ice. The age of the ice may exceed some hundreds or thousands of years. However, structure, formation and development of the ice are not fully understood and are subject to relatively recent investigation. The application of ground-penetrating radar (GPR) enables to determine thickness, volume, basal and internal structure of the ice and provides as such important constraints for related studies. We present results from four caves located in the Northern Calcareous Alps of Austria. We show that the ice is far from being uniform. The base has variable reflection signatures, which is related to the type and size of underlying debris. The internal structure of the cave ice is characterized by banded reflections. These reflection signatures are interpreted as thin layers of sediments and might help to understand the ice formation by representing isochrones. Overall, the relatively low electromagnetic wave speed suggests that the ice is temperate, and that a liquid water content of about 2% is distributed homogenously in the ice.