The geologist may have found some fossils in Sedimentary Rocks A and discovered that they are similar to fossils found in some other rocks in the region.
He would say that the date represents the time when the volcanic lava solidified.
Such an interpretation fits nicely into the range of what he already believes the age to be.
For example, a geologist may examine a cutting where the rocks appear as shown in Figure 1.
Here he can see that some curved sedimentary rocks have been cut vertically by a sheet of volcanic rock called a dyke.
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?by Tas Walker A geologist works out the relative age of a rock by carefully studying where the rock is found in the field.The field relationships, as they are called, are of primary importance and all radiometric dates are evaluated against them.In the same way, by identifying fossils, he may have related Sedimentary Rocks B with some other rocks.Creationists would generally agree with the above methods and use them in their geological work.Let us imagine that the date reported by the lab was 150.7 ± 2.8 million years.