For each dating or chronological method there is a link in the box at right to take you to that section of this page.
Dating is not necessary to demonstrate that evolution is a fact.
Chronological sequence is all that is really required.
Cross-dating is a technique used to take advantage of consistencies in stratigraphy between parts of a site or different sites, and objects or strata with a known relative chronology.
A specialized form of cross-dating, using animal and plant fossils, is known as biostratigraphy.
This is made up of numerous regional tree-ring chronologies, particularly in the medieval and post-medieval periods, for which the laboratory now has more than 200 reference chronologies from many areas. By comparing the proportion of K-40 to Ar-40 in a sample of volcanic rock, and knowing the decay rate of K-40, the date that the rock formed can be determined.
There are over 130 radiocarbon dating laboratories around the world producing radiocarbon assays for the scientific community. A series of movie clips walks you through the process.[ While this may be true, a shrub in Tasmania could be 40,000 years old.See Oldest Living Organism.] The Sheffield Laboratory now has a continuous master sequence for England going back to about 5000BC. This article should be a "must read" for any person interested in factualy accurate information on dating methods.The most compelling argument for an age of the earth of 4.5 billion years are the large number of independent tests that have been used to confirm this date.These tests have been performed on what are thought to be the earth's oldest surviving rocks, meteorites, and moon rocks.Further, he proposed that wherever uncontorted layers were exposed, the bottom layer was deposited first and was, therefore, the oldest layer exposed; each succeeding layer, up to the topmost one, was progressively younger.