Roll the Rock Cycle: Where Does Earth's Material Spend Its Time?

Investigation question: If every rock-cycle change is a roll of the dice, where does rock material pile up, which routes does it take, and how do the results change when we rewrite the rules for a different place on Earth?

Your role today

• Roller: Rolls the die for the current traveler, announces the number, and keeps the die on the desk between rolls.
• Table reader: Finds the current station's table, reads the outcome aloud in full (process, energy source, destination or stay), and confirms the traveler's new station.
• Recorder: Writes one row per roll in the roll log: traveler, station before, roll, process, energy source, station after. Checks that each row's energy source matches the process.
• Tally keeper and reporter: Keeps the running tally of turns at each station, posts the group totals on the class chart, and leads the choice of setting for the modified-rules run.

Safety

• No physical hazards. Keep dice on the desk, not thrown across the room; a dropped die is a trip hazard on a hard floor.
• If the lab is run as a floor game with taped stations, clear bags and chairs from the walking paths and walk, do not run, between stations.

Procedure

1. Read all five station tables aloud as a group. For each table, check that every outcome names a process and an energy source, and say which outcomes are 'stay' and which are 'move.' Note that moving and staying are both allowed results.
2. Place the four traveler tokens on their starting stations: Magma, Sediment, Sedimentary rock, Metamorphic rock. Each traveler will make 10 rolls, one traveler at a time.
3. Run traveler 1. The Roller rolls; the Table reader reads the outcome for the traveler's current station; the Recorder writes the row (traveler, station before, roll, process or 'stays', energy source, station after); the Tally keeper adds a mark under the station where the traveler ends the turn. Move the token. Repeat until 10 rolls are logged.
4. Run travelers 2, 3 and 4 the same way. Rotate the Roller role after each traveler so everyone rolls at least once.
5. Total the tally: how many of the group's 40 turns ended at each station. Calculate each station's percent of the 40 turns and post the group's five counts on the class chart.
6. Trace each traveler's route on the recording sheet as a chain of station names with the process on each arrow. Mark any traveler that never visited Magma and any traveler that skipped from one rock type directly to another rock type.
7. When the class chart is complete, copy the class totals and percents into your sheet and compare them with your group's percents and with the rule probabilities the teacher posts.
8. Choose a setting from the slide. Decide which one or two station tables would be different there and why. On a blank template, rewrite those tables (keep six outcomes, each with a process and an energy source). Write a prediction: which station will gain turns, which will lose.
9. Run two travelers for 10 rolls each with the modified tables, log the rows on the second roll log, and tally. Compare with your prediction.
10. Answer the analysis questions individually.

Record your observations

Lab 3 recording sheet: Roll the rock cycle

Log every roll as one row. If the traveler stays, write 'stays' in the process column and the reason the table gives. The energy source must match the process: Sun and gravity for surface processes, Earth's interior for melting, uplift and heat-and-pressure changes, and 'none needed' when the material simply sits.

Analysis questions