Petrological study as a tool to evaluate the degradation of speleothems in touristic caves, Castañar de Ibor cave, Cáceres, Spain

Abstract

In Castañar cave the surface of most of the speleothems present dissolution and corrosion features. In touristic caves, this process has usually been related to the acidification of the atmospheric moisture caused by CO2 from the breath of visitors. However, in Castañar cave the process of corrosion has been also observed in rooms that are not visited by tourists. Petrological studies were carried out in the speleothems affected by surface corrosion in Castañar cave. The results indicate that this process occurs not only at present time, but over a period of thousands of years, as evidenced by the presence of corrosion lines inside and on the surface of the speleothems. All this and the fact that Castañar cave recovers very quickly from changes in the environmental parameters, indicates that the dissolution-corrosion process is slow and hence it is not related to the presence of visitors.