Theory question 306
Rivers and River Landforms(a) List five landforms found in the upper course of a river. (b) Highlight three differences and two similarities between an alluvial fan and a delta.
Show the model answer
(a) V-shaped valley; gorge; waterfall; rapids; potholes; interlocking spurs; plunge pool; river capture features.
(b) Differences: an alluvial fan forms on land at the foot of a highland where a stream leaves a steep valley, a delta forms where a river enters a sea or lake; alluvial fans contain coarse material (gravel, boulders), deltas mostly fine silt and clay; alluvial fans are common in dry areas and are often dry, deltas have water most of the time; deltas are larger, with many distributaries; fans slope more steeply.
Similarities: both are depositional features formed by rivers; both are fan- or triangle-shaped; both form where the river suddenly loses speed; both are made of alluvium; both have streams dividing into several channels.
Three differences and two similarities exactly.