Geology · Year 12

Active learning ideas

Hydrogeology: Groundwater Resources

Explore the hidden world of groundwater, the planet's largest accessible source of fresh water, and uncover the geological controls on its storage and flow.

• National Curriculum Attainment Targets
• A-Level Geology (Eduqas): Theme 3 - Geological Resources
• A-Level Geology (OCR): Learner Group 3 - Interpreting the Earth

• 30–60 min
• Pairs → Whole Class
• 3 activities

Activity 01

• Experiential Learning
• 50 min · Pairs

Porosity and Permeability Practical

Students measure the porosity and permeability of different materials like sand, gravel, and clay. They pour a known volume of water into a beaker filled with the material to calculate pore space, and then time how long it takes for water to drain through to compare permeability.

Explain the difference between porosity and permeability using examples of common rock types.

Facilitation Tip

Ensure students compact the clay sample to demonstrate how high porosity does not always mean high permeability.

What to look for

Students complete a card sort activity, matching key terms (e.g., aquifer, aquitard) with their definitions and example rock types.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 02

• Experiential Learning
• 30 min · Whole Class

Aquifer in a Tank

Create a model aquifer in a clear plastic tank using layers of gravel (aquifer), sand (aquitard), and clay (aquiclude). Students can observe the water table, simulate rainfall for recharge, and use a small pump or syringe to demonstrate the formation of a cone of depression during abstraction.

Compare the characteristics of a confined and an unconfined aquifer.

Facilitation Tip

Add a few drops of food colouring to represent a pollutant to visualise how it spreads differently in confined versus unconfined aquifers.

What to look for

An exam-style question presenting a geological cross-section of a coastal area. Students must identify the different types of aquifers, explain the risks of saltwater intrusion due to over-abstraction, and suggest management strategies.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 03

• Case Study Analysis
• 60 min · Small Groups

UK Aquifer Case Study Analysis

In small groups, students research a specific UK aquifer, such as the Chalk aquifer or the Permo-Triassic sandstones. They use data from the Environment Agency or British Geological Survey to analyse abstraction rates, water quality issues, and management strategies, presenting their findings to the class.

Analyse the causes and consequences of over-abstraction from an aquifer, such as the formation of a cone of depression.

Facilitation Tip

Provide a structured worksheet to guide their research on key aspects like geology, water use, and environmental impacts.

What to look for

Students use a RAG (Red, Amber, Green) rating system to assess their confidence against the learning objectives before and after the topic is taught.

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management

A few notes on teaching this unit

Start with physical models and analogies to build a strong conceptual foundation for porosity and permeability. Use clear, well-annotated diagrams to build up from a simple unconfined aquifer to more complex confined systems. Then, introduce human interaction through case studies, encouraging students to apply their knowledge to analyse problems and propose solutions.

Students will be able to explain how different rock types function as aquifers and analyse the real-world consequences of our reliance on this vital resource.

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Watch Out for These Misconceptions

• Groundwater exists as vast underground rivers or lakes.

  Groundwater is primarily held within the tiny pore spaces between grains of rock or sediment, or in fractures. It moves very slowly through these interconnected spaces, rather than flowing like a surface river.

• A rock with high porosity must also have high permeability.

  Porosity is the measure of void space, while permeability is a measure of how well those spaces are connected. A rock like clay can have high porosity but very low permeability because the pore spaces are not well connected, preventing water from flowing through it easily.

• The water table is a flat, level surface.

  The water table is rarely flat. It typically mimics the overlying topography, rising under hills and falling in valleys where it may intersect the surface as springs, rivers, or lakes. Its level also fluctuates with seasons and abstraction rates.

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Methods used in this brief

• Experiential Learning
• Case Study Analysis