Upon encountering a new site, the archaeologist immediately requires information about its age in order to set it in context with other sites.In research into our heritage the conservationist or architect may be able to date the general period of a building he is working with from either the situation, materials of construction, type of timber joints or other stylistic features.Carbon dating is somewhat accurate because we are able to determine what the ratio was in the unobservable past to a certain extent.By taking a carboniferous specimen of known age (that is, a specimen which we are able to date with reasonable certainty through some archaeological means), scientists are able to determine what the ratio was during a specimen's lifetime.None is infallible and before embarking on an extensive dating survey, due thought must be given to what might be achieved and which methods might be the more successful. Whilst earlier types of wooden joints may be copied in later buildings and earlier styles may be reintroduced in later periods to confound the conservationist or historian, any reuse of older materials should become obvious by the use of the chronometrical methods described here.The incorporation of ancient bog oak into a building, no matter how intricately carved or jointed, would immediately become obvious to the chronologist, as would timber renovations.Asteroids are usually referred to as being a solid rock from outer space whereas comets are usually a mixture of ice and rock and typically burn up before hitting the earth.
There are over forty such techniques, each using a different radioactive element or a different way of measuring them. In order for carbon dating to be accurate, we must know what the ratio of carbon-12 to carbon-14 was in the environment in which our specimen lived during its lifetime.during the industrial revolution more carbon-12 was being produced offsetting the ratio a bit).These are: dendrochronology (or 'tree-ring' dating), radiocarbon dating and thermoluminescence dating.Each method has a distinct role in the investigation of historic buildings. Furthermore, the ratio is known to fluctuate significantly over relatively short periods of time (e.g.