Stratigraphic column dating
Using fossils simply for identification purposes, Smith constructed a map of the various surface rocks outcropping throughout England, Wales, and southern Scotland.
Almost without exception, the relative order of strata defined by fossils has been confirmed by radiometric ages.
In this example, archaeologists might radiocarbon date the basket fragment or bone awl in Stratum E, and they could use artifact seriation to obtain fairly precise date ranges for Strata A, B, C, and E.
If the date on the car license plate is preserved, they can say with certainty that Stratum A was deposited in that year or later.
Suppose, too, that all the layers contain a good representation of the animal life existing at the time of deposition.
From an examination of such outcrops with special focus on the sequence of animal forms comes the empirical generalization that the faunas of the past have followed a specific order of succession, and so the relative age of a fossiliferous rock is indicated by the types of fossils it contains.fossil assemblages.
The basis for assuming that like fossils indicate contemporary formation is faunal succession.