Which of the following is not a chronometric dating method alt extreme 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.Dendrochronology has been extended in the American southwest to 322 BC, by adding increasingly older archaeological samples to the record.
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.
Each tree then, contains a record of rainfall for the length of its life, expressed in density, trace element content, stable isotope composition, and intra-annual growth ring width.
Using local pine trees, Douglass built a 450 year record of the tree ring variability.
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.