Carbon dating zooarchaeology
Carbon dating zooarchaeology - Dirty chatbots
The amount of carbon 14 remaining in the material to date is compared to a reference standard (ratio 14C/total carbon, 12C and 13C) to calculate the time elapsed since its occurrence.
Relative dating includes different techniques, but the most commonly used are soil stratigraphy analysis and typology.
Indeed, some items whose exact or approximate age is known are called "diagnostic artifacts." Examples of such objects include very specific stone tools, different pottery styles, objects that belong to a specific period (eg, the historic period or the French regime), coins with a production date, or other items bearing a trademark and whose history can be traced in historical records.
Their presence on archaeological sites is used to date the soil layers and the objects and events they are associated with and thus contributes to refine the chronology of sites.
This is the only type of techniques that can help clarifying the actual age of an object.
Absolute dating methods mainly include radiocarbon dating, dendrochronology and thermoluminescence.
An initial reading dates the specimen which is then calibrated by considering this date and its correspondence with the measurable level of carbon 14 stored over time in the growth rings of certain tree species, including redwood and pine bristol.
The results of radiocarbon dating are expressed in years and include a time range (eg, 630± 60 BP).However, this method is sometimes limited because the reoccupation of an area may require excavation to establish the foundation of a building, for instance, that goes through older layers.In this case, even if the foundation of the building is found in the same stratigraphic level as the previous occupation, the two events are not contemporary.Several sets of rings from different trees are matched to build an average sequence.Subsequently, overlapping series of average sequences from trees that died at different times and come from various sources (ie, the wood of historic buildings, archaeological and fossil woods) are used to build a chronological sequence covering several hundred years which becomes a reference.Dendrochronology Dendrochronology is a method that studies the rings of tree trunks to define characteristic sequences by analyzing the morphology of growth rings for a given species.