Radioactive dating of rocks
What would our geologist have thought if the date from the lab had been greater than 200 million years, say 350.5 ± 4.3 million years?
Would he have concluded that the fossil date for the sediments was wrong? Would he have thought that the radiometric dating method was flawed? Instead of questioning the method, he would say that the radiometric date was not recording the time that the rock solidified.
Here he can see that some curved sedimentary rocks have been cut vertically by a sheet of volcanic rock called a dyke.
It is clear that the sedimentary rock was deposited and folded before the dyke was squeezed into place.
Play a game that tests your ability to match the percentage of the dating element that remains to the age of the object.
by Tas Walker A geologist works out the relative age of a rock by carefully studying where the rock is found in the field.
Even different samples of rock collected from the same outcrop would give a larger scatter of results. He would again say that the calculated age did not represent the time when the rock solidified.
In the same way, by identifying fossils, he may have related Sedimentary Rocks B with some other rocks.Thus, he already ‘knows’ that the igneous dyke must be younger than 200 million years and older than 30 million years.(Creationists do not agree with these ages of millions of years because of the assumptions they are based on.) Because of his interest in the volcanic dyke, he collects a sample, being careful to select rock that looks fresh and unaltered.Or he may suggest that the result was due to a characteristic of the lava—that the dyke had inherited an old ‘age’. 200.4 ± 3.2 million years) implies that the calculated date of 200.4 million years is accurate to plus or minus 3.2 million years.In other words, the age should lie between 197.2 million years and 203.6 million years.