THE DEEP-TIME LAB
Deep-Time Walkway Planner
Give geological time a physical scale. Plan a measured timeline for your classroom, corridor or museum, with a placement sheet and teacher discussion prompts.
Earth history fits in your hallway
Walk through time.
10 m
4,600 → 0 Ma · Earth history
Ma = million years ago; older to the left. Mixed ranks: Precambrian is an informal span, Paleozoic and Cenozoic are eras; the Mesozoic is expanded into its three periods.
Every metre represents
460 million years
Position formula
Distance from start = (oldest age − event age) ÷ total duration × walkway length
| Event / marker | Ma | From start (m) | From finish (cm) |
|---|---|---|---|
| Earth forms (rounded) | 4,600 | 0 | 1,000 |
| Cambrian begins | 538.8 | 8.8287 | 117.13 |
| Triassic begins | 251.902 | 9.4524 | 54.761 |
| Early dinosaurs (approx.) | 230 | 9.5 | 50 |
| Jurassic begins | 201.4 | 9.5622 | 43.783 |
| Cretaceous begins | 143.1 | 9.6889 | 31.109 |
| K–Pg extinction boundary | 66 | 9.8565 | 14.348 |
| Quaternary begins | 2.58 | 9.9944 | 0.561 |
| Present | 0 | 10 | 0 |
Decimals help with placement; they do not imply equivalent dating precision. If markers are closer than your tape can resolve, use a longer walkway or a Phanerozoic / Mesozoic window. Do not space the events equally.
Prints current values. Expand teacher answers to include them.
Classroom investigation · suggested ages 10–14
Predict. Measure. Explain.
Goal: convert time to distance, measure a scale model and explain why recent events cluster near the finish.
- Mark the start 4600 Ma and the finish 0 Ma. Have each group choose an event, calculate its position independently, then check the table.
- Walk the timeline in order. Which markers are hard to distinguish, and how could you adjust the model?
- If the walkway doubles in length, what happens to marker distances and the amount of time per metre?
Teacher answers & discussion
- Position = (4600 − event Ma) ÷ 4,600 × 10 metres. Measure from the same starting point to avoid cumulative errors.
- Short intervals cluster in an Earth-history model. Extend the walkway or narrow the time window to separate markers, keeping all distances proportional.
- Distances from the start double. Time per metre halves from 460 to 230 million years.
Geological boundaries use central values from ICS 2026/06; dating uncertainties are not plotted. Early dinosaurs use a rounded 230 Ma marker. The 4600 Ma Earth origin is a classroom convention, not a formal stratigraphic boundary.
ICS 2026/06 ↗ · USGS: age of Earth ↗ · NHM: dinosaur origins ↗
Free to project and print this activity for non-commercial teaching with credit and sources retained. Ages and timing are planning suggestions, not classroom-trial results. AI-assisted; independent expert review is not claimed. More teaching materials ↗