A) Every Pb2+ atom detected in the zircon sample must be the result of radioactive decay, while some Pb2+ atoms found in sphene could have been incorporated during its formation.
Explanation:
The reason why the geochemist will prefer to use the ziron which takes the 4+ cation would be because, every Pb2+ atom detected in the zircon sample must be the result of radioactive decay, while some Pb2+ atoms found in sphene could have been incorporated during its formation.
✓ The Pb 2+ produced the daughter isotopes of the radioactive decays.
✓ To properly date the rock sample, any external source of the daughter isotopes should be eradicated.
✓ This will help to establish a fair ratio between the parent and daughter isotopes in order to track the decay rate.
✓ This is why the Zircon would be preferred to the Sphene.
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<span>they made many glaciers that are yet to melt and the also lowered the temperature that we have today </span>
Answer:
i think d, but i am not sure
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