Investigation of Ancient Sites and Sources: Dating Methods Flashcards
Relative Dating
Stratigraphic Dating
Dating different levels of strata to establish a chronological sequence.
The strata closer to the surface are younger than those before.
Can be unreliable, such as if erosion changes the original context in which the artefacts were deposited.
Relative Dating
Typology Dating
Groups of pottery, tools, or weapons can be arranged in a sequence from earliest to latest types based on the following principles:
1. All artefacts belonging to a particular period have distinctive features based on their materials, shape and decoration.
2. Over a long period of time, these artefacts will show gradual changes. Early samples are simple, later samples are more elaborate.
Relative Dating
The Three-Age System
Ancient artefacts are organised into Stone, Bronze, and Iron ages.
The Stone Age is divided into Palaeolithic, Mesolithic and Neolithic.
The Bronze Age is divided into Early, Middle, and Late periods.
Absolute Dating
Radiocarbon Dating
Scientists can measure the radioactive emissions of carbon-14 in a sample of organism to determine when the organism died.
Dates organic materials between 50,000 and 400 years old
Absolute Dating
AMS Radiocarbon Dating
Accelerator Mass Spectronomy
A more sophisticated radiocarbon dating.
Dates materials back to 70,000 years
More accurate and requires much smaller samples. Materials that might contaminate the samples can be reduced, produces faster results.
Absolute Dating
Dendrochronology
The age of a tree or any timber objects made from trees can be determined by counting growth rings in a cross-section.
Archaeologists can produce a master sequence for a region going back thousands of years. Trees growing in the same region will have a similar pattern of ring growth. Archaeologists then match the pattern of growth rings in timber rings with the master sequence of the region, enabling them to calculate a date for the stratum the timber was found in.
Absolute Dating
Potassium-argon dating
Dates volcanic rock up to millions of years old.
Absolute Dating
Uranium-series dating
Dates rocks containing calcium carbonate (stalagmite and other cave formations).
Useful for periods between 50,000 and 500,000 years old.
Absolute Dating
Fission-track dating
Application of radioactive dating to determine the thermal age of artefacts containing uranium-bearing minerals.
Can date between 20 and 100 million years ago. Dates glass, stone, and fired ceramics.
Verifies dates obtained from K-Ar dating.
Absolute Dating
Thermoluminescence
Dates pottery and inorganic material that’s up to 50,000 years old.
Scientists measure the light emitted and radioactive content of the sample to determine the original firing date of the pottery.
Can determine the authenticity of potentially fake artefacts.