Earth resources
Introduced| English | Meaning |
|---|---|
| water cycle/ˈwɔːtə ˈsaɪkl/ | The continuous movement of water between the atmosphere, land and bodies of water. |
| rock cycle/rɒk ˈsaɪkl/ | The interconnected processes that form and transform igneous, sedimentary and metamorphic rocks through different possible pathways. |
| igneous/ˈɪɡnɪəs/ | igneous |
| sedimentary/ˌsedɪˈmentəri/ | sedimentary |
| metamorphic/ˌmetəˈmɔːfɪk/ | metamorphic |
| renewable/rɪˈnjuːəbl/ | Describing a resource that can be replenished naturally on a timescale relevant to its use. |
| non-renewable/nɒn rɪˈnjuːəbl/ | Describing a resource used faster than natural processes replace it on a human timescale. |
A water cycle does not balance every pond
- An invented pond receives 30 m³ over a stated period, loses 18 m³ through its outlet and 7 m³ by evaporation. With no other inputs or losses in this simplified model, storage increases by 5 m³.
- A water cycle 水循环 moves water through evaporation, condensation, precipitation, runoff, infiltration and groundwater. Water crossing a pond's boundary can change its local storage.
Which statement fits the simplified local pond water cycle and budget?
Difficulty 1/5 · 100 coins + a small bonus on first completion today
The pond is open to inflow, rainfall, outlet loss and evaporation. A local budget does not prove exact constancy for all water on Earth.
Write the local budget before recommending use
- Storage change follows $\Delta S=\text{inputs}-\text{losses}$. Here, $\Delta S=30-18-7=5\ \text{m}^3$; this is a change, not the pond's total volume.
- Proposed extra extraction of 12 m³ gives $\Delta S=30-18-7-12=-7\ \text{m}^3$. Without starting storage and other constraints, the record cannot say whether the pond would empty.
Inputs are 30 m³, outlet loss 18 m³ and evaporation 7 m³. What is storage change in m³?
Difficulty 2/5 · 140 coins + a small bonus on first completion today
ΔS = 30 - 18 - 7 = 5 m³.
Under the same budget, add extraction of 12 m³. What is storage change in m³?
Difficulty 2/5 · 140 coins + a small bonus on first completion today
ΔS = 30 - 18 - 7 - 12 = -7 m³; this does not specify starting storage.
Distinguish rock-formation processes
- In the rock cycle 岩石循环, igneous 火成岩 rock forms when molten material cools and solidifies. Sedimentary 沉积岩 rock can form when deposited sediment becomes consolidated through compaction and cementation; some forms have other deposition routes.
- Metamorphic 变质岩 rock forms when existing rock changes under heat and pressure without melting. If it melts, later cooling can form igneous rock; not every rock follows one compulsory sequence.
Match each rock type to how it forms.
Difficulty 2/5 · 140 coins + a small bonus on first completion today
Formation processes provide different routes. The rock cycle is not one compulsory sequence for every rock, and a photograph alone does not establish exact age.
A rock that fully melts and then cools into a solid has formed metamorphic rock by that melting process.
Difficulty 1/5 · 100 coins + a small bonus on first completion today
False: crystallisation from molten material forms igneous rock; metamorphic change occurs without melting.
Compare replenishment with use
- A renewable 可再生 resource can replenish on a relevant timescale; a non-renewable 不可再生 resource does not replenish fast enough relative to human use. Renewable does not mean unlimited.
- A forest producing 100 units of new wood while 130 units are harvested loses 30 units under this simplified budget. Regrowth potential alone does not make that harvest sustainable.
A forest is harvested faster than regrowth replaces it. Which interpretation is supported?
Difficulty 1/5 · 100 coins + a small bonus on first completion today
Compare use and replenishment over a stated period. Renewable potential does not guarantee sustainable use or approval.
Fossil fuels are non-renewable because the process that forms them has stopped.
Difficulty 1/5 · 100 coins + a small bonus on first completion today
Formation and replacement are too slow relative to human use. Non-renewable does not mean no related geological process occurs.
Keep availability separate from safety and age
- Reeds at a pond do not establish drinking-water safety. A water-volume budget cannot replace measurements relevant to water quality or ecosystem requirements.
- A rock photograph can show features, but does not establish every rock's identity or exact age. Cite the actual measurements, maps, methods and dates used for a conclusion.
Use the supplied record for analysis. A calculated increase in storage does not give permission to extract water or establish long-term sustainable use.
Conserve useful resources, not only atoms
- Matter conservation does not guarantee that material remains concentrated, accessible or useful. Disposal can scatter or mix material, making recovery harder and more energy-demanding.
- Report the boundary, period, starting information and assumptions. Keep rock formation, local water storage and resource-use decisions as related but distinct questions.
A cycle describes processes; a budget tracks a defined stock. Replenishment, usable supply, safety and approval each need relevant evidence.
In one sentence, explain why recycling matters even though matter is conserved.
Difficulty 3/5 · 200 coins + a small bonus on first completion today
Example: “Matter can remain present but dispersed or mixed, making useful recovery more difficult.” A conservation statement does not guarantee local availability or unlimited usable supply.