Start Advantages and disadvantages of radiocarbon dating

Advantages and disadvantages of radiocarbon dating

However, there are a number of other factors that can affect the amount of carbon present in a sample and how that information is interpreted by archaeologists.

By comparing the amount of carbon 14 remaining in a sample with a modern standard, we can determine when the organism died, as for example, when a shellfish was collected or a tree cut down.

Compared to conventional radiocarbon techniques such as Libby's solid carbon counting, the gas counting method popular in the mid-1950s, or liquid scintillation (LS) counting, AMS permitted the dating of much smaller sized samples with even greater precision.

Regardless of the particular 14C technique used, the value of this tool for archaeology has clearly been appreciated.

Desmond Clark (1979:7) observed that without radiocarbon dating "we would still be foundering in a sea of imprecisions sometime bred of inspired guesswork but more often of imaginative speculation." And as Colin Renfrew (1973) aptly noted over 30 years ago, the "Radiocarbon Revolution" transformed how archaeologists could interpret the past and track cultural changes through a period in human history where we see among other things the massive migration of peoples settling virtually every major region of the world, the transition from hunting and gathering to more intensive forms of food production, and the rise of city-states.

However, as with any dating technique there are limits to the kinds of things that can be satisfactorily dated, levels of precision and accuracy, age range constraints, and different levels of susceptibility to contamination.

The introduction of "old" or "artificial" carbon into the atmosphere (i.e., the "Suess Effect" and "Atom Bomb Effect", respectively) can influence the ages of dates making them appear older or younger than they actually are.

This is a major concern for bone dates where pretreatment procedures must be employed to isolate protein or a specific amino acid such as hydroxyproline (known to occur almost exclusively in bone collagen) to ensure accurate age assessments of bone specimens.

For example, rootlet intrusion, soil type (e.g., limestone carbonates), and handling of the specimens in the field or lab (e.g., accidental introduction of tobacco ash, hair, or fibers) can all potentially affect the age of a sample.