Cryogenic carbonates and cryogenic speleothem damage in the za hájovnou cave (Javoříčko karst, Czech Republic)

Abstract

A new locality of coarse-grained cryogenic cave carbonates has been found in the Za Hájovnou Cave in Javoříčko Karst in Central Moravia, Czech Republic. Crystals and crystal aggregates, usually up to 15 mm in size, form typical loose accumula-tions on the surface of large fallen limestone blocks and clays covering the bottoms of several cave chambers distant from the cave entrance. The cryogenic origin of the carbonates is supported by their mode of occurrence, specific crystal and ag-gregate morphology, and C and O stable isotope data. U-series dating of one sample of cryogenic carbonate (age 29.5 ±0.1 ka) indicated that a period of karst water freezing occurred in marine isotope stage (MIS) 3, within the Weichselian. The cave also hosts numerous examples of speleothem damage. As shown in this paper, some of these are clearly connected with freezing conditions and cave ice action.