Task: Modeling Tectonic Landscapes

Anchoring Phenomenon: Mountains don’t last forever, yet there are still mountains on Earth today. If wind and water are constantly wearing down rocks, why hasn’t Earth’s surface been completely flattened out?

Part 1: Engage

Look at a photo of a rugged mountain range like the Himalayas, and a photo of a rounded, older mountain range like the Appalachians.

1. What do you notice about the shapes of the peaks in both pictures? _____
2. What natural forces do you think are responsible for making mountains tall, and what forces are responsible for wearing them down? _____
3. What questions do you have about how mountains change over long periods of time? _____

Part 2: Explore

Open the Tectonic Landscape Modeler simulation. This model allows you to speed up geologic time (where 1 unit of time = 1 million years) and observe how different forces shape the land.

1. Constructive Forces (Building Up):
   • Ensure the simulation time is paused.
   • Select the Tectonic Uplift tool. Set the Intensity slider to 5.
   • Click and drag across the landmass to create a mountain range.
   • Now select the Volcano tool, set Intensity to 8, and click repeatedly in one spot to build a volcanic peak.
   • Sketch or describe the shape of the land features you created. _____
2. Destructive Forces (Wearing Down):
   • Select the Weathering/Erosion tool. Set Intensity to 5.
   • Click and drag over the peaks you just built. Observe what happens.
   • Now select the Mass Wasting tool (landslides/rockfalls) and click near the top of a steep peak.
   • Describe how weathering/erosion differs from mass wasting in the simulation. _____
3. Temporal Scale (Geologic Time):
   • Click Reset World.
   • Build a single large mountain using the Tectonic Uplift tool.
   • Click Play Time to start geologic time. Watch the “Geologic Time” counter.
   • Without using any tools yourself, observe what happens to the mountain over 10 million, 50 million, and 100 million years.
   • Record your observations in the table below:

Part 3: Explain

Using the data and observations from your exploration, answer the following questions:

1. Constructive vs. Destructive Forces: Which tools in the simulation act as “constructive forces,” and which act as “destructive mechanisms”? Explain your reasoning based on how they changed the landscape. _____
2. Spatial Scale: How did the location of your constructive forces determine where valleys and mountains formed? _____
3. Temporal Scale: The slow, continuous weathering that happened when you clicked “Play Time” represents global erosion over millions of years. How does this compare to the sudden collapse caused by the Mass Wasting tool? Why is it important to consider different time scales (temporal scales) when studying Earth’s surface? _____

Part 4: Elaborate / Evaluate

Develop a Model: Use evidence from the simulation to develop a written or sketched model explaining how the interaction of internal processes (uplift/volcanism) and surface processes (weathering/erosion) operate to form and change continental features over time.

Your model must include:

• Descriptions and locations of specific continental features (e.g., mountains, valleys).
• Identification of internal processes (constructive) and surface processes (destructive).
• An explanation of the relationship between these processes (e.g., how uplift creates high ground that is then acted upon by erosion).
• Reference to the temporal scale over which these processes operate (slow vs. rapid).

Extension Options:

1. Investigate how different types of rock (e.g., granite vs. sandstone) might weather differently over time, and research which simulated tool settings best mimic these specific rock types.
2. Research a specific geological feature, such as the Grand Canyon or the Hawaiian Islands, and describe how the simulation’s constructive and destructive forces could be used to model its formation.

Teacher Notes

NGSS Alignment:

• Performance Expectation: HS-ESS2-1: Develop a model to illustrate how Earth’s internal and surface processes operate at different spatial and temporal scales to form continental and ocean-floor features.
• Science and Engineering Practice (SEP): Developing and Using Models: Develop a model based on evidence to illustrate the relationships between systems or between components of a system.
• Disciplinary Core Ideas (DCI):
  • ESS2.A: Earth Materials and Systems (Earth’s systems cause feedback effects).
  • ESS2.B: Plate Tectonics and Large-Scale System Interactions (Plate movements are responsible for most continental features).
• Crosscutting Concept (CCC): Stability and Change: Change and rates of change can be quantified and modeled over very short or very long periods of time.

Evidence Statements Addressed:

• 1.a.i: Descriptions and locations of specific continental features. (Addressed in Part 4 model development).
• 1.a.iii: Internal processes (such as volcanism and tectonic uplift) and surface processes (such as weathering and erosion). (Addressed in Part 2 and Part 3).
• 1.a.iv: A temporal scale showing the relative times over which processes act. (Addressed in Part 2 Geologic Time and Part 3).
• 2.a.i: Specific internal processes are identified as causal agents in building up Earth’s surface over time. (Addressed in Part 3 and Part 4).
• 2.a.ii: Specific surface processes are identified as causal agents in wearing down Earth’s surface over time. (Addressed in Part 3 and Part 4).
• 2.a.iv: The rate at which features change is related to the time scale. (Addressed in Part 3 and Part 4).

Estimated Time: 45-60 minutes Materials: Device with internet access, Tectonic Landscape Modeler simulation, task handout.