prize9-6, Exercise 2: River or glacier valley?

Model answer (check the details):

Clues of a glacier:
1. A U-shaped cross-section with steep sides and a flat floor, where a river valley is V-shaped.
2. Hanging valleys, with side streams dropping as waterfalls from high above the main valley floor.
3. Corries and sharp ridges (arêtes) at the head of the valley, and often a truncated, straightened course instead of winding spurs.

Other clues: moraines, erratic boulders, scratched rock surfaces, a long thin lake or sea loch on the valley floor.

Care: many valleys were cut by rivers first and reshaped by ice, so both sets of features can occur together.