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S5 Geography | Coastal Landforms Paper 2 (Advanced)
S5 Geography | Coastal Landforms Paper 2 (Advanced)
Paper 2 widens the frame: one coast has to be costed for erosion rate, sediment budget and defence cost per metre per year, and mixing units is how wrong options get chosen.
Attempt first, mark afterwards Allow about twenty-five minutes; convert everything to per metre per year or cubic metres per year first, then decide whether the question asks for a total, a rate or a gap.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 items |
| Suggested time | About 25 minutes |
| Difficulty mix | Foundation 3 · Intermediate 4 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: S5 Geography | Coastal Landforms |
| Level | S5 (Secondary 5) Geography |
02 Questions (10 items)
- FoundationA sea cave has cut 4 m into the cliff and deepens by 0.25 m a year. When do two caves meet to form an arch, and how long in total until the arch collapses into a stack 24 years later?
- FoundationLongshore drift carries 5,000 cubic metres a year and a spit is 500 m long, 40 m wide and 1.5 m thick on average. How many years of deposition does that represent?
- FoundationSea level rises 4.0 mm a year. With a beach slope of 1 in 50, how much does the sea rise in 50 years and how far does the shoreline move inland?
- IntermediateOn one coast a shale cliff retreats 0.8 m a year and a granite cliff 0.05 m a year. How much do the two differ after 40 years, and how many times faster is the shale?
- IntermediateA 1200 m sea wall costs 60,000,000 dollars and lasts 30 years. Alternatively, beach nourishment every 4 years uses 12,000 cubic metres of sand at 20 dollars a cubic metre along 800 m. What is the cost per metre per year for each?
- IntermediateThe mean tidal range is 2.4 m and the intertidal beach slope is 1 in 40. Roughly how wide is the intertidal zone?
- IntermediateA coast gains 15,000 cubic metres a year from rivers, loses 9,000 offshore and is dredged for 2,000. Keeping the present beach width actually needs a net 6,000. What is the real budget, the shortfall, and the annual retreat if the beach is 1000 m long and 2 m thick?
- ChallengeLongshore drift of 12,000 cubic metres a year is fully trapped by a groyne. Downstream the beach is 600 m long, 30 m wide and 2 m thick. How long before it is stripped, and how much builds up on the up-drift side meanwhile?
- ChallengeTwo options for the same coast: hard engineering costs 8,000 dollars a metre once plus 40 a metre a year; soft engineering costs 900 a metre every 5 years. Over 50 years, what does each cost per metre and what is the gap?
- Error redoA student writes that a groyne traps longshore drift so the sand stays put and the whole coast benefits. What is wrong with that?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 16 years to break through, 40 years in total. | 4 divided by 0.25 gives 16 years, plus 24 years before collapse, so 40 years overall; caves are eroded from both sides and the roof fails only after it is undermined. |
| 2 | About 6 years. | The spit holds 500 times 40 times 1.5, or 30,000 cubic metres; dividing by 5,000 gives 6 years, since a spit builds where the coastline turns and drift loses energy. |
| 3 | A rise of 0.2 m and a landward shift of 10 m. | 4.0 mm times 50 gives 200 mm, or 0.2 m, and times 50 gives 10 m; the gentler the slope, the wider the strip lost for the same rise. |
| 4 | A difference of 30 m, and the shale retreats 16 times as fast. | 0.8 times 40 gives 32 m against 2 m, a gap of 30 m; the ratio is 16, which is why soft rock forms bays and hard rock stands out as headlands. |
| 5 | The wall is about 1,666.67 dollars and nourishment about 75 dollars per metre per year. | Wall: 60,000,000 over 1200 is 50,000 a metre, over 30 years 1,666.67. Nourishment: 12,000 times 20 is 240,000 dollars, over 800 m is 300, over 4 years 75; only per metre per year can the two be compared. |
| 6 | About 96 m. | 2.4 times 40 gives 96 m; the tidal range sets how much ground is flooded and exposed each day, so a large range on a gentle slope produces a very wide intertidal zone. |
| 7 | A net gain of 4,000, a shortfall of 2,000 cubic metres and a retreat of 1 m a year. | 15,000 less 9,000 less 2,000 is 4,000; the shortfall is 2,000, and dividing by 1000 times 2 gives 1 m. A positive budget is not stability unless it meets the amount needed to hold the width. |
| 8 | About 3 years, with 36,000 cubic metres piling up on the other side. | The downstream volume is 600 times 30 times 2, or 36,000 cubic metres, which at 12,000 a year lasts 3 years; the up-drift side gains the same 36,000, so the sediment is merely moved, not lost. |
| 9 | Hard 10,000 dollars, soft 9,000 dollars, a gap of 1,000. | Hard: 8,000 plus 40 times 50 is 10,000. Soft: 10 rounds at 900 each is 9,000. Soft is cheaper but only holds the beach, not the cliff foot, so the choice depends on what is being protected. |
| 10 | The error is the claim about the whole coast: a groyne starves the down-drift side, so the total sediment is unchanged and erosion is moved, not removed. | Drift moves one way, so a groyne piles sand up-drift and starves the beach down-drift; that is why groynes are usually paired with nourishment. A good answer names both affected stretches instead of saying erosion is prevented. |
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.