Two types of absolute dating
In general, academic fields such as archaeology that research material culture associated with the cultural behaviour in human history, dating artefacts is one of the foremost priorities. To this end, the easiest way is to depend on historic records, but historical materials only provide limited information as to the scope of space and time. When scientists are able to determine the age of rocks and fossils, they can then tell a more accurate story of the Earths history.When Geologists and other scientists refer to the age of the Earth, they are using one of two methods to determine this.Before more precise absolute dating tools were possible, researchers used a variety of comparative approaches called relative dating.These methods — some of which are still used today — provide only an approximate spot within a previously established sequence: Think of it as ordering rather than dating.
In this context, the cultural and art historical importance and its associated monetary value have fuelled the row regarding when the object was manufactured and in what way the year of the piece’s production could be scientifically confirmed.
Sometimes only one method is possible, reducing the confidence researchers have in the results. “They’re based on ‘it’s that old because I say so,’ a popular approach by some of my older colleagues,” says Shea, laughing, “though I find I like it myself as I get more gray hair.” Kidding aside, dating a find is crucial for understanding its significance and relation to other fossils or artifacts.
Methods fall into one of two categories: relative or absolute.
This problem is now reduced by the careful collection of samples, rigorous crosschecking and the use of newer techniques that can date minute samples.
Volcanic rocks – such as tuff and basalt – can be used in dating because they are formed at a particular moment in time, during an eruption.
Knowing when a dinosaur or other animal lived is important because it helps us place them on the evolutionary family tree.