Relative Dating Excavation Lab
You are a geologist and you have been asked to correlate the rock columns from three different
archaeological digs. You will excavate the earth layers to determine the relative ages of the
layers. As you carefully examine each layer think about what you see, feel, uncover, and how
you might use this information to determine the age of each layer.
1. Review concepts and information on Correlation
2. Examine your samples and think about what you will be looking for prior to starting
3. In your groups determine the best way to chart your data. It should be clear as to what
you are finding and where.
4. You will want to digitally document this excavation, so prepare the webcam.
5. You will also need to record the findings so one team member needs to record the
findings in the iNB chart. This team member must share accurate data with the rest of the
team.
Now that you are set up let’s begin
Materials
Material
Amount (SI Units)
500 mL plastic beakers with samples of
earth layers
spoon (regular table size)
1
Science spatula
1
100 mL plastic beaker
6
5 L plastic tub
1
Web Cam
1
Tac-pen
Shell
Paperclip
3
Hershey Kiss
Eraser
Pop cicle stick
Leaf
Relative Dating Excavation Lab
Procedures:
1. All members need to wear aprons so as to not stain clothing. There are no safety concerns for
this lab, however students with long hair need to pen it back to no to contaminate the
excavation.
2. Prepare all materials according to materials list and have conversion chart “Time Lived on
Earth” visible once excavation begins.
3. Label samples in 500mL beakers A, B, & C.
4. Label 100mL beakers L1 – L6 for layers 1-6.
5. Student Excavator will select sample A.
6. Excavator will examine top layer to determine type of rock.
7. Student Recorder will mark it on the chart in the iNB
8. Excavator will then carefully scrape and “dig” through the layer removing the rock from only
that layer.
9. Place the rock material and fossil if found in the 100mL beaker labels “layer 1”.
10. When the Excavator discovers a fossil, he/she will show it to the Recorder and Student
Photographer.
11. The Photographer will take a picture using the Web Cam and paste it into the TecActive Flip
Chart for documentation. Photographer must label each picture for accuracy (digital journal).
12. The Recorder will record the fossil finding in the iNB chart.
13. Repeat steps 6-12 for all layers in sample A.
14. Repeat steps 5-12 replacing sample A with sample B.
15. Repeat steps 5-12 replacing sample A with sample C.
16. Once the data has been recorded clean up the lab and the area. Rock layers must be put into
labeled tubs and beakers washed. NOTE: sand, dirt, and rock are to be rinsed and disposed of
outside – not in the sink!
Now answer the questions below on the output page of your iNB:
1. Differentiate: which fossils in the key appear to be index fossils? Explain and use
examples.
2. Match: Correlate layer A-2 to one layer in each of the other two columns. Determine
the approximate age of these layers. Explain how you found your answer.
3. Infer: Use evidence from the excavation to determine the approximate age of layer B-4.
In complete sentences explain what information you used and how is was helpful in
finding your answer.
4. Write: Using a Sum-it-Up explain how fossils can be used to determine the relative ages
of rocks.
Relative Dating Excavation Lab
Extension:
Now that you have complete the excavation and recorded your data you need to report your
finding.
To do this you will be conducting a video interview for an on-line science magazine.
You will each develop three questions the interviewer can use to ask the “geologist” about the
excavation. The magazine will also have a few questions as well.
Questions from the magazine:
1. What was the purpose of this excavation?
2. We have heard a lot about Alfred Wagener and his theory of Continental Drift. How
does the findings from this excavation help to prove or disprove this theory?
3. What evidence do you have to support your claim?
Your questions:
4. How far back in time do these fossils date?
5. What type of dating did you use? How reliable is this type of dating?
6. What was the most interesting fossil you found?
7. Can you explain the results? What did your data show?
8. Were there any procedural errors during the excavation?
9. Did you have a team helping you record your findings?
10. Please explain how excavations such as the one you just completed can be used to help us
understand the Earth better.
11. How can this information help industries or governments in the real world?
Relative Dating Excavation Lab
Now that you have your questions it’s time to conduct the interview.
Excavator – Geologist
Recorder – Interviewer
Photographer – Cameraperson
Take a few minutes and decide how you want to set up the “stage”.
Test the lighting and the equipment to unsure it is all working properly.
Ensure the Interview is ready with questions and has rehearsed them so he/she will speak clearly.
Relax. Lights. Camera. Action. 4-3-…
You may do as many takes as you need – but you must complete it and save it before the end of
the period. The interview is an assessment grade!