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S4 Geography: River Landforms – Intermediate Practice (10 Questions)
S4 Geography: River Landforms – Intermediate Practice (10 Questions)
Ten items focus on valley development and simple calculations: lateral erosion, downcutting rates, Strahler order, meander migration, runoff volume, flood peaks, sinuosity and the effect of dams.
Quick answer 1. broad shallow trough, lateral erosion; 2. 5 cm; 3. second order; 4. 100 m; 5. about 2 × 10⁸ m³; 6. four times; 7. 1.5; 8. supply trapped, deposition lags erosion; 9. gravel, sand, silt, clay; 10. energy depends on discharge and gradient.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | about 25 minutes |
| Difficulty mix | Foundation 3 · Intermediate 4 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: S4 Geography | River Landforms: erosion, transport, deposition and valley development |
| Level | S4 |
02 Questions (10 items)
- FoundationWhat shape is a lower-course valley cross-section, and which erosion dominates?
- FoundationA river bed is downcut by 0.5 cm each year. How much lowering after 10 years?
- FoundationTwo first-order tributaries join. What is the Strahler order of the stream below the junction?
- IntermediateA meander outer bank retreats 2 m a year. How far has it moved in 50 years?
- IntermediateA 250 km² basin receives 2 000 mm of rain a year with a runoff coefficient of 0.4. What is the annual runoff volume?
- IntermediatePeak discharge rises from 20 m³/s to 80 m³/s. By what factor has it increased?
- IntermediateSinuosity is channel length divided by valley length. With 12 km of channel in an 8 km valley, what is the value?
- ChallengeWhy does a delta retreat after a dam is built upstream?
- ChallengeWhat is the correct order of sediment from coarsest to finest?
- Error redoA student claims river energy depends only on gradient. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | Broad and shallow, trough-shaped, dominated by lateral erosion. | On a gentle lower course the river swings sideways, so the valley is much wider than upstream. |
| 2 | 5 cm. | Multiply the rate by the number of years, though armouring and base level eventually slow it. |
| 3 | Second order. | Equal orders add one, while unequal orders keep the higher value, so 2 plus 1 stays 2. |
| 4 | 100 m. | Meander migration accumulates over decades and can finally cut off an oxbow lake. |
| 5 | About 2 × 10⁸ m³. | Convert the area to 2.5 × 10⁸ m², multiply by 2 m of rain and by 0.4. |
| 6 | Four times. | A fourfold rise in discharge greatly increases both transport power and flood risk. |
| 7 | 1.5. | A value near 1 means a straight channel; above 1.5 is strongly meandering. |
| 8 | The dam traps sediment, so downstream supply collapses and deposition can no longer match erosion and wave attack. | A delta balance depends on river supply against marine removal, and cutting the supply makes it shrink. |
| 9 | Gravel, sand, silt, clay. | Finer grains settle more slowly and travel farther, which is why river mouths are built of fine sediment. |
| 10 | Energy depends on discharge as well as gradient, so a large slow river can still move far more load. | Discharge means mass, so a big gentle river can carry more total energy than a steep small stream. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
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Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.