The laws of physics and chemistry that governed geologic processes in the past are the same as those that govern processes now and in the future.
The geologic timescale is a chronology (calendar) of events on Earth based on obtaining ages of past events.
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.Archaeology dating techniques can assure buyers that their item is not a fake by providing scientific reassurance of the artefact's likely age.Archaeological scientists have two primary ways of telling the age of artefacts and the sites from which they came: relative dating and absolute dating.Relative dating in archaeology presumes the age of an artefact in relation and by comparison, to other objects found in its vicinity.
Limits to relative dating are that it cannot provide an accurate year or a specific date of use. There are two main methods determining a fossils age, relative dating and absolute dating.Relative dating is used to determine a fossils approximate age by comparing it to similar rocks and fossils of known ages.Different methods have their own limitations, especially with regard to the age range they can measure and the substances they can date.A common problem with any dating method is that a sample may be contaminated with older or younger material and give a false age.This approach helps to order events chronologically but it does not provide the absolute age of an object expressed in years.