fission track

American  

noun

1. the evidence or damage left by the decay of uranium atoms in a mineral, helping to estimate the age of a sample of the mineral.

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fission track Scientific  

1. A track left by the decay of uranium atoms in a mineral. By analyzing the number and nature of these tracks in a sample mineral and inducing further fission of the remaining uranium by irradiation with neutrons to create new tracks for comparison, one can estimate the approximate age of the sample.

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