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Rock samples from Marion Island in the Sub-Antarctic and from the Drakensberg, South Africa were divided into sets and subjected to wetting and drying at 2 different moisture amplitudes to determine changes in physical rock properties. Rock porosity
of wetting and drying cycles is a more important factor than the degree to which the samples have been saturated; 2) changes in rock properties were detected for the control samples as well as the field samples, suggesting that the experimental techniques
used for determining the rock properties have themselves affected the samples; 3) samples that outwardly appeared very similar have responded differently to wetting and drying. This implies that even small changes in internal rock structure can have

Cold area ; Geophysics ; Instrumentation ; Rock mechanics ; Temperature ; Thermal stress ; Threshold ; Weathering
Rock surface temperature changes in excess of 2°C min-1 have been argued to result in permanent strain in rock. The single threshold value and the supposed importance of a rate of 2°C min-1 rock temperature change is rejected, based on lack
of a sufficient empirical basis, contrasting results from acoustic emission studies, varying strength properties of different rock types, lack of data on actual strain resulting from short-term temperature variations, and lack of notable long-term weathering

Pronival ramparts are often confused with moraines, protalus rock glaciers or rock-slope failure debris accumulations. Various characteristics have been suggested for identification of pronival ramparts but these are derived largely from relict

for a blockfield, using data collected during the 2009-2012 Austral summer seasons. Proxy data recorded for weathering included rock hardness rebound values as well as visual evidence of flaking, pitting, surface roughness and lichen presence. Aspect was found

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