Corrosion of calcite speleothems in epigenic caves of Moravian Karst (Czech Republic)

Corrosion of calcite speleothems in epigenic caves of Moravian Karst (Czech Republic)

WoS Article

Corrosion processes were studied in epigenic caves of the Moravian Karst (MK). Samples of naturally corroded speleothems and carbonate rocks collected in various MK caves were compared with limestone and calcite standards that were corroded under well-controlled conditions in the laboratory. Two stages of corrosion were distinguished: (1) an early stage of pitting and linear corrosion predisposed by point and line defects in the standards, and (2) an advanced stage characterized by deep corrosion of the entire standard surface. During the second stage, the internal structure of the corroded substrate remained partially preserved, however, if the water was extremely aggressive, the corrosion progressed to depth en-bloc regardless of the structure. In this paper, we (1) proposed a new corrosion mechanism based on the binding of aqueous calcium by clays and tested it experimentally in the cave, (2) characterized conditions that generally favor the formation of aggressive waters (water undersaturated with calcite) into seven categories incorporating them into a conceptual model of the karst vertical profile, and (3) discussed anthropogenic influences on these processes.

Corrosion processes were studied in epigenic caves of the Moravian Karst (MK). Samples of naturally corroded speleothems and carbonate rocks collected in various MK caves were compared with limestone and calcite standards that were corroded under well-controlled conditions in the laboratory. Two stages of corrosion were distinguished: (1) an early stage of pitting and linear corrosion predisposed by point and line defects in the standards, and (2) an advanced stage characterized by deep corrosion of the entire standard surface. During the second stage, the internal structure of the corroded substrate remained partially preserved, however, if the water was extremely aggressive, the corrosion progressed to depth en-bloc regardless of the structure. In this paper, we (1) proposed a new corrosion mechanism based on the binding of aqueous calcium by clays and tested it experimentally in the cave, (2) characterized conditions that generally favor the formation of aggressive waters (water undersaturated with calcite) into seven categories incorporating them into a conceptual model of the karst vertical profile, and (3) discussed anthropogenic influences on these processes.

Corrosion; Calcite speleothem; Epigenic cave; Karst vertical profile; Water aggressivity

Corrosion; Calcite speleothem; Epigenic cave; Karst vertical profile; Water aggressivity

FAIMON, J.; BALDÍK, V.; ŠTELCL, J.; VŠIANSKÝ, D.; REZ, J.; PRACNÝ, P.; NOVOTNÝ, R.; LANG, M.; ROUBAL, Z.; SZABÓ, Z.; HADACZ, R.

2025

14.03.2024

Springer

NEW YORK

1866-6299

Environmental Earth Sciences

83

6

Federal Republic of Germany

1

20

20

https://link.springer.com/article/10.1007/s12665-024-11449-w

http://hdl.handle.net/11012/249923

s12665-024-11449-w