A deep valley with steep upper walls that grade into a flat floor, usually eroded by a glacier.
A valley with a U-shaped cross-section caused by glacial erosion. Contrast with the V-shape of a typical stream valley.
The U-shaped valleys (or beheaded glacial valleys) that form Sun Notch and Kerr Notch were carved by glaciers on Mount Mazama. The glaciers had retreated far up the volcano when the caldera collapsed, beheading these and other, less spectacular valleys at the caldera wall. Glacial valley is shaped like a U, whereas stream valley (V-shaped valley carved by water) is shaped like a V.
a sign that a glacier had been there once before
A valley with a parabolic or "U" shaped cross-section, steep walls and generally a broad and flat floor. Formed by glacier erosion, a U-shaped valley results when a glacier widens and over-steepens a V-shaped stream valley.
A glacially carved valley having a pronounced parabolic cross-sectional profile suggesting the form of a broad letter "U" and characterized by steep sides and a nearly flat bottom.
A U-shaped valley is one formed by the process of glaciation. It has a characteristic U-shape, with steep, straight sides, and a flat bottom. Glaciated valleys are formed when a glacier travels across and down a slope, carving the valley by the action of scouring.