Absolute dating archeology
Correlation of fossil inclusions is a principle of stratigraphy: that strata may be correlated based on the sequence and uniqueness of their floral and faunal content.
The amount of carbon dioxide in the living organism is equal to that in the atmosphere.
Because the concentration of radiocarbon in the atmosphere has varied considerably over time, radiocarbon dates as far back as 7,000 years may be corrected by calibrating them against accurate dates from radiocarbon-dated tree rings and developing a master correction curve.
Archeologists use a statistical standard deviation to increase the range of dates for a sample that has been given a C14 date.
with a standard deviation of plus or minus 120 years, the chances are two in three that that sample dates from between 1120 and 880 BC.
Here's how: Calculations based on one standard deviation of 120 years: 1000 120 = 1120 BC (Oldest date) 1000 - 120 = 880 BC (Most recent date) To increase the range of possible dates of a sample, archeologists may calculate the radiocarbon date to two standard deviations.