Potassium argon is an example of a relative dating technique
When it comes to determining the age of stuff scientists dig out of the ground, whether fossil or artifact, “there are good dates and bad dates and ugly dates,” says paleoanthropologist John Shea of Stony Brook University.The good dates are confirmed using at least two different methods, ideally involving multiple independent labs for each method to cross-check results.This concept called the (the date after which) is of particular importance to archaeologists dealing with the historic period. Exercises: Ask the students to exchange their items with others in the class to guess their use. Your local archeologist may be able to furnish suitable materials, or the sequences in the publications listed below may be used for illustration. Then ask the students to arrange them in sets according to distinctive characteristics. Who made it, a specialized craftsman or an ordinary member of the society? The time line generated by your students will introduce them to the important concept of stratigraphy, as well as to the goal of archaeology: to reconstruct past lifeways and place them in a chronological framework in order to better understand the present. This technique dates a site based on the relative frequency of types of artifacts whose dates of use or manufacture are known. The kinds of questions they should ask are: Is it made of wood, paper, cloth, metal, pottery? Is it for personal care, decoration, or amusement, or does it have a utilitarian purpose? Were the materials used in its manufacture from the local area or from far away? The categories for classification will be suggested by the objects in the assemblage.
Natural processes like frost heaving, erosion, and the down-slope movement of soils in colder climates (solifluction) can alter the original context in which the artifacts were deposited.
This is the concept of --or the Law of Superposition.
Stratigraphic sequences in the field, however, are sometimes unreliable.
But absolute dating methods are not always useful; the particular circumstances to which they apply do not exist at every site.
Dating methods, such as radiocarbon dating, dendro-chronology or tree-ring dating, and potassium-argon dating, that may furnish an date for an archaeological site, are a contribution of the physical and the natural sciences.