O Level Geography Physical Geography Quiz

O-Level Geography Quiz - Physical Geography (Answer Key)

Total Marks: 45

Section A: Tectonics and Physical Processes (Questions 1-5)

1. Earth Structure (a) Crust [1] (b) Liquid (or molten) [1]

2. Earthquake Distribution (a)

• Concentrated along plate boundaries. [1]
• Specifically along the Pacific Ring of Fire. [1] (b)
• Plate interiors are stable/far from boundaries. [1]
• Little stress/friction accumulation to cause quakes. [1]

3. Coastal Landforms (a) Spit [1] (b)

• Waves approach coast at an angle due to prevailing wind. [1]
• Swash moves sediment up at angle; backwash moves down at 90 degrees. [1]
• Net movement of sediment along coast (longshore drift). [1]

4. Plate Boundaries (a) Plates move apart (diverge). [1] (b)

• Subduction of denser oceanic plate under lighter plate. [1]
• Friction/melting creates magma which rises to form volcanoes. [1]
• Example: Andes Mountains / Volcanic Arc. [1]

5. Volcanoes (a) Main Vent (or Pipe) [1] (b)

• High silica content magma is viscous/thick. [1]
• Gas builds up pressure and explodes when released. [1]

Section B: Climate and Weather (Questions 6-10)

6. Climate Data (a)

• Working: 24 - 10 [1]
• Answer: 14°C [1] (b)
• High rainfall year-round. [1]
• No distinct dry season / Rainfall > 150mm most months. [1]

7. Enhanced Greenhouse Effect

• Greenhouse gases trap long-wave radiation from Earth. [1]
• Human activities (e.g., burning fossil fuels) increase CO2 levels. [1]
• More heat is trapped in the atmosphere. [1]
• Leads to global warming. [1]

8. Urban Heat Island (a) Urban areas are warmer than surrounding rural areas. [1] (b)

• Concrete/asphalt absorbs and stores more heat than vegetation. [1]
• Lack of vegetation reduces cooling via evapotranspiration. [1]
• Heat generated by human activities (cars, AC, industry). [1]

9. Rain Gauge (a) To avoid rain shadow or splash-back from obstacles (trees/buildings). [1] (b)

• Obstacles block rain or cause splash-in. [1]
• Data becomes inaccurate (under/over estimated). [1]

10. Climate Comparison (a) Both have high temperatures (in summer/day). [1] (b)

• Equatorial has high rainfall year-round. [1]
• Desert has very low rainfall / irregular rainfall. [1]

Section C: Data Interpretation and Fieldwork Methods (Questions 11-15)

11. Variables (a) Distance from the sea. [1] (b) Sediment size. [1]

12. Methods (a)

• Sieves provide objective/quantitative data. [1]
• Eye estimation is subjective/prone to error. [1] (b) Use systematic sampling (e.g., every 10m) or random sampling. [1]

13. Wave Height and Slope (a) Positive correlation. [1]

• As wave height increases, slope angle increases. [1] (b)
• High energy waves deposit coarse material. [1]
• Coarse material allows water to percolate, reducing backwash, creating steeper angle. [1]

14. Questionnaires (a) Advantage: Collects primary data on people's opinions/awareness. [1] (b) Disadvantage: People may lie or give biased answers. [1]

15. Safety (a) Slipping on wet rocks / Being swept away by waves. [1] (b) Wear appropriate footwear (studded boots) / Check tide times. [1]

Section D: Extended Response (Questions 16-20)

16. Tectonic Hazards: Human vs Physical Factors (9 Marks)

• Level 3 (7-9 marks): Balanced argument. Acknowledges physical magnitude but argues human factors (development, preparation, density) determine impact severity. Uses specific case studies (e.g., Haiti vs Chile, or Japan). Clear conclusion.
• Level 2 (4-6 marks): Describes factors but may be unbalanced. Some case study detail.
• Level 1 (1-3 marks): Basic statements. Limited explanation.

17. Causes of Global Climate Change (6 Marks)

• Natural Causes: Volcanic eruptions (ash blocks sun), changes in solar output, orbital changes. [Up to 3 marks]
• Human Causes: Burning fossil fuels (CO2), deforestation (less absorption), agriculture (methane). [Up to 3 marks]
• Note: Award marks for explanation of mechanism, not just listing.

18. Formation of a Meander (6 Marks)

• River flows around slight bend. [1]
• Faster flow on outside bend causes erosion (undercutting bank). [1]
• Slower flow on inside bend causes deposition (slip-off slope). [1]
• This exaggerates the bend over time. [1]
• Helicoidal flow contributes to this process. [1]
• Diagram or clear sequence of events. [1]

19. Water Supply Challenges (6 Marks)

• Physical: Droughts, uneven distribution, pollution of sources. [Up to 3 marks]
• Human: Population growth, industrial demand, poor infrastructure/leakage, cost of desalination. [Up to 3 marks]
• Example: Singapore (reliance on imports/NEWater) or California (droughts).

20. Hard Engineering Coastal Management (6 Marks)

• Strategies: Sea walls, groynes, rock armour. [1]
• Effectiveness: Sea walls reflect energy but are expensive and ugly. [1]
• Groynes trap sediment but starve beaches further down coast. [1]
• Evaluation: Effective in short term for protecting specific assets. [1]
• But can disrupt natural processes and shift problem elsewhere. [1]
• Often unsustainable compared to soft engineering. [1]