| Term: | Ogive |
| Definition: | Arcuate bands or waves, convex downglacier, that develop in an icefall. Alternating light and dark bands are called banded ogives or Forbes bands. Each pair of bands, that is, one crest (light) and one trough (dark), represents a year's movement through the icefall. It can be shown that, to yield visible banding, ice must flow through the icefall in a time shorter than the duration of the ablation season or accumulation season. James Forbes was the first to describe ogives, in 1843. |