formation of a hanging valley

Snow Accumulation

BEFORE

snow accumulates in north facing hollow due to more snow falling in winter than melting in summer. north facing hollows are more shaded so snow lies for longer, allowing it to compress into neve then ice.

Glacial Flow

BEFORE

glaciers flow downhill due to gravity and weight.

tributaries

BEFORE

tributary glaciers fill tributary valleys

Plucking

DURING

ice freezes onto bedrock and pulls loose rocks away from the sides, making them steeper.

Abrasion

DURING

angular rocks embedded in the ice grind the base, making it deeper.

Truncated Spurs

DURING

Former interlocking spurs may be cut off by the glacier as it flows downhill, leaving truncated spurs and steep valley sides.

Hanging Valleys

AFTER

hanging valleys form as tributary glaciers have less power to erode and so form smaller valleys which are left hanging above the main valley

Waterfalls

AFTER

Rivers that flow in hanging valleys often descend to the main valley as waterfalls.

An example of a hanging valley in the Lake District

Grisedale Valley