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C) dating usually want to know about the radiometric dating methods that are claimed to give millions and billions of years—carbon dating can only give thousands of years.
Levels of carbon-14 become difficult to measure and compare after about 50,000 years (between 8 and 9 half lives; where 1% of the original carbon-14 would remain undecayed).
The question should be whether or not carbon-14 can be used to date any artifacts at all? There are a few categories of artifacts that can be dated using carbon-14; however, they cannot be more 50,000 years old.
The age of the carbon in the rock is different from that of the carbon in the air and makes carbon dating data for those organisms inaccurate under the assumptions normally used for carbon dating.
This restriction extends to animals that consume seafood in their diet.
We will deal with carbon dating first and then with the other dating methods.One rare form has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or C ratio gets smaller.So, we have a “clock” which starts ticking the moment something dies.Two dating scenarios for the fossils were tested by varying the assumed levels of Rn loss in the encasing sediments: a maximum age scenario provides an average age for the two least altered fossil teeth of 253 82/–70 ka, whilst a minimum age scenario yields an average age of 200 70/–61 ka.We consider the maximum age scenario to more closely reflect conditions in the cave, and therefore, the true age of the fossils.