29 year old rock paintings in the Alpine karren field of Innerbergli (Siebenhengste, Switzerland) prevented the underlying rock from corrosion, while the surface nearby was corroded. Measurement of the steps indicates an average recent corrosion rate of 0.014 (±0.007) mm/a. This denudation rate is very similar to those observed in other comparable places and with other means.
Surface corrosion of an Alpine karren field: recent measures at Innerbergli (Siebenhengste, Switzerland).
International Journal of Speleology,
Available at: http://scholarcommons.usf.edu/ijs/vol37/iss2/3