Use this interactive to work out the relative ages of some rock layers from youngest to oldest. Drag and drop the text labels onto the diagram.
We’ve found this cliff. Help us work out the relative ages of the layers of sedimentary rocks. Remember that the younger sedimentary rocks lie on top of older ones and were horizontal when formed. It looks as though one group of layers was tilted and eroded away before new rocks were formed on top.
Drag and drop the text labels next to the layer you think is being described. If you want to redo an answer, click on the box and the answer will go back to the top so you can move it to another box. If you want to check your answers, use the reset incorrect button, which will reset incorrect answers only. When you are satisfied with your selection, use the check answers button to check them. Reset all to practise again from the start.
Once you have finished the interactive, watch the animation to see how we think the layers were formed.
For optimal viewing of this interactive, view at your screen's default zoom setting (100%) and with your browser window view maximised.
| Label | Description |
| Last before tilt | This was the last layer to be formed before the rocks tilted. |
| Oldest rock | This rock layer is below all the others. |
| Youngest rock | This is the youngest rock above all the others. |
| Second-oldest rock | This rock layer is just above the oldest. |
| Thinnest rock | This is the thinnest rock layer. |
| Above the erosion | This layer formed on top of earlier rocks after they were tilted and eroded away. |
