3 assumptions of radiometric dating
And, of course, the reported error ignores the huge uncertainties in the Creationist physicists point to several lines of evidence that decay rates have been faster in the past, and propose a pulse of accelerated decay during Creation Week, and possibly a smaller pulse during the Flood year. He may suggest that some of the chemicals in the rock had been disturbed by groundwater or weathering.What would our geologist think if the date from the lab were less than 30 million years, say 10.1 ± 1.8 million years? Or he may decide that the rock had been affected by a localized heating event—one strong enough to disturb the chemicals, but not strong enough to be visible in the field.The field relationships are generally broad, and a wide range of ‘dates’ can be interpreted as the time when the lava solidified.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.He may suggest that the rock contained crystals (called xenocrysts) that formed long before the rock solidified and that these crystals gave an older date.In the same way, by identifying fossils, he may have related Sedimentary Rocks B with some other rocks.
Such an interpretation fits nicely into the range of what he already believes the age to be.
(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.
On his return, he sends his sample to the laboratory for dating, and after a few weeks receives the lab report.
From the mapped field relationships, it is a simple matter to work out a geological cross-section and the relative timing of the geologic events.
His geological cross-section may look something like Figure 2.