Relative chronometric dating methods
SYNONYMS OR RELATED TERMS: chronometric dating; absolute dates; absolute chronology; absolute age determination (antonym: relative dating)CATEGORY: chronology; technique DEFINITION: The determination of age with reference to a specific time scale, such as a fixed calendrical system or in years before present (B.P., BP), based on measurable physical and chemical qualities or historical associations such as coins and written records.For those researchers working in the field of human history, the chronology of events remains a major element of reflection.Archaeologists have access to various techniques for dating archaeological sites or the objects found on those sites.In the Southwest, and particularly in CRM, there are several defined types of survey: Remote Sensing: Remote sensing in archeology employs a wide variety of aerial and satellite imaging, as well as radar, sonar and lidar, to build landscape images useful for recognizing archeological materials not visible to ground crews.Many remote sensing techniques rely on portions of the electromagnetic spectrum, such as infrared, that humans are typically unable to see.Stratigraphy is the oldest of the relative dating methods that archaeologists use to date things.
Archeological excavations, or “digs,” are conducted using very specific methods and rigorous vertical and horizontal spatial controls. Relative dating in archeology determines the age of cultural material in relation to other cultural material, but does not produce precise dates.
In other words, artifacts found in the upper layers of a site will have been deposited more recently than those found in the lower layers.
Cross-dating of sites, comparing geologic strata at one site with another location and extrapolating the relative ages in that manner, is still an important dating strategy used today, primarily when sites are far too old for absolute dates to have much meaning.
For example, JJA Worsaae used this law to prove the Three Age System.
For more information on stratigraphy and how it is used in archaeology, see the Stratigraphy glossary entry.
Archaeologists use many different techniques to determine the age of a particular artifact, site, or part of a site.