Located in the valley of the same name, the city first formed between 150 BCE and 200 CE and benefitted from a plentiful supply of spring water which was channelled through irrigation.The largest structures at the site were completed before the 3rd century CE, and the city reached its peak in the 4th century CE with a population as high as 200,000.Adding the margin of error for carbon-14 (in this case, /- 150 years), the archaeologist can give a reliable date range for the bone: 1655-1405 B. A bone found deep in the ground will generally be older than one found close to the surface, for example.Two bones found in the same archaeological deposit are likely to be the same age.Voyage into Archaeology Links, articles, and other beginner's resources in archaeology, including a simulation game called "Be a Time Detective." Glossary of Archaeological Terms What is chert? For example, the arrival of sophisticated carbon-14 dating methods in the 1940s caused scientists to revise their interpretation of events in Europe in prehistoric times. Accurate dating is important for putting events and objects in sequence.
Thermoluminescence dating is used for rocks, minerals, ceramics and burned features.
When an archeologist has identified the source of the obsidian from which an artifact is made, he or she may be able to date the artifact using the obsidian hydration technique.
This technique of dating obsidian artifacts measures the microscopic amount of water absorbed on freshly broken surfaces.
The principle behind obsidian hydration dating is simple—the longer the artifact surface has been exposed, the thicker the hydration band will be.
Obsidian hydration can indicate an artifact's age if the datable surfaces tested are only those exposed by flintknapping.