Chronometric dating techniques based
His research culminated in proving that tree ring width varies with annual rainfall.Not only that, it varies regionally, such that all trees within a specific species and region will show the same relative growth during wet years and dry years.For example, JJA Worsaae used this law to prove the Three Age System.
Douglass believed that solar flares affected climate, and hence the amount of growth a tree might gain in a given year.
Seriation is thought to be the first application of statistics in archaeology. The most famous seriation study was probably Deetz and Dethlefsen's study Death's Head, Cherub, Urn and Willow, on changing styles on gravestones in New England cemeteries.
The method is still a standard for cemetery studies.
Archaeologists use many different techniques to determine the age of a particular artifact, site, or part of a site.
Two broad categories of dating or chronometric techniques that archaeologists use are called relative and absolute dating.
Determining calendar rates using dendrochronology is a matter of matching known patterns of light and dark rings to those recorded by Douglass and his successors.