Also found in: Thesaurus, Encyclopedia, Wikipedia.
An accumulation of boulders, stones, or other debris carried and deposited by a glacier.
[French, from French dialectal morena, mound of earth, from Provençal morre, muzzle, from Vulgar Latin *murrum.]
mo·rain′al, mo·rain′ic adj.
(Physical Geography) a mass of debris, carried by glaciers and forming ridges and mounds when deposited
[C18: from French, from Savoy dialect morena, of obscure origin]
moˈrainal, moˈrainic adj
1. a ridge, mound, or irregular mass of unstratified glacial drift, chiefly boulders, gravel, sand, and clay.
2. a deposit of such material left on the ground by a glacier.
[1780–90; < French < Franco-Provençal morêna rise in the ground =mour(o) mound + -ena suffix of landforms]
mo•rain′al, mo•rain′ic, adj.
A mass of boulders, pebbles, sand, and mud deposited in the form of a long ridge along the front or sides of a glacier. Moraines typically form because of the plowing effect of a moving glacier, which causes it to pick up rock fragments and sediments as it moves, and because of the periodic melting of the ice, which causes the glacier to deposit these materials during warmer intervals. ♦ A moraine that forms in front of a glacier is a terminal moraine. ♦ A moraine that forms along the side of a glacier is a lateral moraine.
Rock debris moved or dumped by a melting glacier or ice sheet.