Learning how to constuct a graph of a decaying isotope and using it in radiometric dating

This activity is written by Ntungwa Maasha, of the College of Coastal Georgia based on the original activity from Richard M. Busch of West Chester university of Pennsylvania
College of Coastal Georgia, Natural Science
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In this exercise students will learn how to construct a decay curve for a radioactive isotope and how to use it in determining the age of an object.

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Learning Goals

Learning outcomes of this exercise:
  • To plot the natural decay curve for a radioactive isotope during decay
  • To plot the curve of daughter atoms produced by radioactive isotope
  • To use the curves to work sample problems on absolute dating

Methods of Geoscience

The activity is meant to show student how to represent data graphically. In particular the emphasis is the the natural decay curve.
This exercise what inspired by a real situation in class. it was observed that several students needed extraordinary help in completing the laboratory exercise on radiometric dating. The problem disappeared when this supplement was introduced.

Context for Use

An exercise the course laboratory manual requires students to use decay curves to infer radiometric ages of rocks. This exercise is meant to give the student an idea about how the decay curve is constructed and how decay of radioactive isotope is related to the presence of the daughter atoms.

Description and Teaching Materials

Required Items: paper, pencil, graph paper, calculator
Radiometric Dating -suplement to existing activity (Acrobat (PDF) 277kB May7 12)

Teaching Notes and Tips

There are no additional notes on this activity


This is not the complete activity. Assessment is done for the complete laboratory activity modified with this complement.

References and Resources

There are no additional resources needed.