•Twenty automatic crack
gauge monitors were installed
across several major South Peak
fissures
•Measure submillimetre
trends including thermal expansion
of bedrock
•Installed in sets of three
in order to resolve movement vectors
With a maximum range of 50
mm (2 inches), these are very sensitive to movements and have been impacted
significantly by snow loading, which typically extends at least four of these
instruments beyond their working range each season, leading to replacement.