Errors in Radiometric Dating

The daughter product came from an alternative source, other than radioactive decay

• makes the rock seem older

If the daughter element is gaseous it may diffuse out of the rock

• makes rock seem younger

If the daughter element is gaseous it may diffuse into a rock

• makes rock seem older

Parent isotope could be gained from an alternative source

• makes rock seem younger

Metamorphism

• rock seems younger as it allows the parent:daughter ratio to change (reset)

Uncertainty over the exact half life makes rocks seem older or younger

If the daughter product an be produced by another decay series involving a different parent the rock seems older

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