Composition and origin of amber ice and its influence on the behaviour of cold glaciers in the McMurdo Dry Valleys, Antarctica.

The article examines the composition, structure and deformation of amber ice as well as its influence on Rhone Glacier's behaviour in the McMurdo Dry Valleys in Antarctica. The basal ice sequence of the cold-based glacier was investigated using isotopic and solute chemistry data. The study identifies three different ice facies including englacial, amber and stratified. The analysis of stratified facies shows an isotopic signature which indicates melt then refreeze processes and is most likely associated with apron entrainment. It was found out that impurities in the amber ice has prolonged contact with the bed and that depleted isotopic signature is consistent with ice formed during a cooler period.