Most till consists predominantly of clay, silt, and sand, but with pebbles, cobbles, and boulders scattered through the till.- Till (Wikipedia)
Till or glacial till is unsorted glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes.