Method of historical dating
Amino acid dating: This relatively new form of absolute dating is useful in archaeology, anthropology, paleobiology, molecular biology and anything else that may study organic substances to pinpoint an actual date or define a date range.
It's found a great use in the tracking of human migrations in antiquity, demonstrating earlier arrival of humans into North America - pushing dates back from 15,000 years to 50,000 years (4).
Amino Acid Dating is used to acquire dates numbering in the hundreds of thousands, although some calibration is required to account for local temperature conditions. Paleomagnetic / Archaeomagnetic dating: By studying the changes in the magnetic signature of deposits, artefacts, but particularly soil disturbance, archaeologists and paleontologists can determine precise dates.
There are two ways a magnetic signature forms - firstly through extreme heat such as in pottery production or hearth fires.
Similarly, herbchronology examines the growth rings in perennial plants other than trees to come up with the same information.
Such rings can tell us the year the plant or tree was cleared; it can also shed light on geological or environmental events that alter the environment.
However, some other areas apply the same or similar principles in dating.
Luminescence/Thermoluminescence: This measures the amount of light emitted from energy stored in rocks.
Geological materials store energy from the sun at a constant and known rate.
These energy levels are measured against what they should be if they had not been interfered with and we are able to obtain a date of the intervention.
This is used in archaeological and anthropological contexts (7) in areas where radiocarbon dating is problematic such as dating post AD1700 and where dates from RC14 is anomalous or lacks data. Potassium-argon dating: Typically used in geology and geochronology, K-Ar dating has a minimum age of around 100,000 years ago (but can be problematic when examining material close to this earliest date) up to a top end of around 4.5 billion years.For example, a tree ring pattern may show lower growth during a volcanic eruption.