Observations on rapid mass movement and screes on Sub-Antarctic Marion Island

Translational and rotational slides, together with debris flows, constitute the predominant contemporary rapid mass movement features in peat areas that overly grey and black basaltic lava on Maritime Sub-Antarctic Marion Island. Rapid mass movements on peat slopes frequently take place in low altitude areas (<350 m a.s.l.) and appear to be the major factor of slope development in vegetated areas on Marion Island. Relict screes are present in grey lava areas where high free faces provided the source for slope debris material and findings suggest that major scree production occurred during a period of more intensive periglacial activity than present; in the Feldmark Plateau area findings suggest an ice-free period longer than has previously been proposed for Marion Island.