Some Major Absolute Dating Techniques Used in Archaeology Today
|
METHOD
|
MATERIAL
REQUIRED
|
AGE RANGE
|
EXAMPLE
|
|
Dendrochronology
|
Large
pieces of wood with visible tree ring structure
|
0-12,000
years
|
Wooden
beams from Viking ship
|
|
Radiocarbon
|
Organic
material; wood, bone, shell, leather, hair, plant remains
|
300-45,000 years
|
Charcoal
from an ancient fire hearth
|
|
Argon-Argon
(Ar-Ar)
|
Volcanic
rock or ash
|
100,000-billions of years
|
Lava
flows covering fossil-bearing deposits
|
|
Uranium
Series
|
Bone,
shell, calcite
|
10,000-500,000 years
|
Fossil
bone from a limestone cave
|
|
Thermoluminescence
|
Fired
clay, pottery
(dates
last time heated)
|
0-100,000 years
|
Fired
clay vessel, sherds, figurines, daub
|
|
Electronic spin resonance
|
Tooth
enamel, calcite, bone
|
1,000-300,000+ years
|
Tooth
from a fossil hominid
|
|
Archaeomagnetism
|
Pottery,
clay, soil, rocks
|
0-30,000
years
|
Burned
clay house floors
|
|
Obsidian
Hydration
|
Obsidian
|
0-500,000 years
|
a thin
section from a projectile point
|
All are Absolute dating methods. Why? Because you get a precise
numeric (not relative) date using each.
Some of the above are Chronometric dating methods, including Dendrochronology, Archaeomagnetism and Obsidian Hydration. But only some are Radiometric dating methods - those based on known, measurable decay rates of radioactive isotopes. These include radiocarbon (14C), Argon-Argon, Uranium Series, and Thermoluminescence. In the end, though, all are Absolute dating methods because they give you absolute, not relative dates.
What are some relative dating techniques? Stratigraphy, Seriation and terminus post quem, right? Right!