Glacial depositional landforms

• Glacial debris- Rock enters glacial system and is transported along. This is then classified by 1 of 3 types of debris. Supraglacial- material at the top of ice. Englacial- material within the ice, happens via falling through crevasses through extensional flow. Subglacial- material at the bottom of ice.
• Erratics- debris carried by glacier through Freeze thaw, plucking or erosion of valley sides. Transported by the glacier and deposited when ablation increases and the weight is too heavy. It is possible to trace the provenance of the erratic through the geology of it e.g. Erratics found in boulder clay in Northumberland travelled from Scandinavia.
• The formation of lowland depositional features-Lodgement till- beneath an ice mass where subglacial till becomes lodged in glacier bed. Is generally rounded because of the grinding that occurs at the ice- bed interface. Is released once sediment load is too high and glacier can no longer carry it.
• Ablation till- When glacier starts to melt and can no longer carry the debris and so dumps it. Can be supraglacial, englacial and subglacial. Unsorted and angular as they are not truly ground down