fluted moraine A ground moraine surface which shows streamlined ridges and grooves trending (see TREND) at right angles to the ice front. Individual ridges are generally less than 1 km long, and less than 10 m high. They may form as a consequence of high vertical ice pressure forcing a subglacial, plastic till up into the low-pressure zone downglacier of a large boulder.

fluted moraine A ground moraine surface which shows streamlined ridges and grooves trending at right angles to the ice front. Individual ridges are generally less than 1 km long and less than 10 m high. They may form as a consequence of high vertical ice pressure forcing a subglacial, plastic till up into the low-pressure zone down-glacier of a large boulder.