Fig. 14From: Cold-based glaciation of Pavonis Mons, Mars: evidence for moraine deposition during glacial advanceSketch of proposed mechanism for ridge deposition. a Sublimation lag develops on surface of ice sheet. b Ice accumulation on the flanks of Pavonis produces a velocity wave which collects surface debris. c Debris is deposited at the ice margin and subsequently overridden by the advancing ice sheetBack to article page