Radiometric Dating Basics
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In plain terms
Some minerals act like clocks: radioactive atoms change at a known rate, and we measure the result.
Key ideas
- Half-life: time for half the parent isotope to decay.
- Parent/daughter: parent decays into daughter isotopes.
- Closure temperature: when a mineral “locks in” the isotopic ratio.
- What an age means: often the time of crystallization or cooling, not necessarily deposition.
Key takeaways
- Choose the right mineral/system for the question.
- Context determines what the age represents.
- Heat and fluids can reset clocks.
- Multiple lines of evidence improve confidence.
- Radiometric ages complement relative dating.