Glaciological controls on debris cover formation are investigated from the perspective of primary dispersal of supraglacial debris across a melting ice surface. This involves the migration of angled debris septa outcrops across a melting, thinning
glacier ablation zone. First, simple geometric relations between englacial septa and the supraglacial debris load are outlined to elucidate the role of glaciological variables (gradient, ice motion, ablation, rate of glacier thinning) on debris cover