Forms of relative dating
states, “Before the 20th century, archaeologists and geologists were largely limited to the use of relative dating techniques.
Estimates of the absolute age of prehistoric and geological events and remains amounted to little more than inspired guesswork, as there was no scientific basis for testing such proposals.” With this background, it is strange that the “standard geologic column” that identifies the rock strata on the earth and assigns very old ages to those strata was developed by Sir Charles Lyell in 1830.
Cultural seriations are based on typologies, in which artifacts that are numerous across a wide variety of sites and over time, like pottery or stone tools.
If archaeologists know how pottery styles, glazes, and techniques have changed over time they can date sites based on the ratio of different kinds of pottery.
Other methods include fluorine dating, nitrogen dating, association with bones of extinct fauna, association with certain pollen profiles, association with geological features such as beaches, terraces and river meanders, and the establishment of cultural seriations.
This also works with stone tools which are found abundantly at different sites and across long periods of time.
Stratigraphic dating is based on the principle of depositional superposition of layers of sediments called strata.
The majority of chronometric dating methods are radiometric, which means they involve measuring the radioactive decay of a certain chemical isotope.
They are called chronometric because they allow one to make a very accurate scientific estimate of the date of an object as expressed in years.