Radioactive carbon dating problems consolidating schools in pa
Thus the physical principle of the method is well established. The dates obtained by radiometric dating are verified by independent methods, including dendrochronology (tree rings), varve chronology (sediment layers), ice cores, coral banding, speleotherms (cave formations), fission track dating, and electron spin resonance dating.
The multiple checks verify that the rate of isotope decay does not change over time, and it verifies the accuracies of the methods.
Every few years, new geologic time scales are published, providing the latest dates for major time lines.
Older dates may change by a few million years up and down, but younger dates are stable.
Sediment columns giving an unbroken history for more than 25,000 years have been identified in about 30 locations around the world.
Coral growth patterns are also seasonal and provide a long independent date history. The dates obtained by different radiometric isotope pairs cross-check each other.
The actual accuracy of radiometric dating is about 2%, but there is no point in splitting hairs for this debate as to whether it is 2% or 3%.
An error of 90% would, for example, still disprove Young Earth Creationism.
For example, the C14 concentration in the atmosphere depends upon cosmic ray intensity.
To take this into account, a calibration curve is developed using other dating methods to establish the C14 levels over time.
Methods are precise insofar as they are properly used.
A good explanation of all of the dating methods used for samples up to about 200,000 years old, together with their accuracies and references to the scientific literature is contained in  Walker, Mike, "Quaternary Dating Methods," John Wiley & Sons, 2005
Measuring the ratio of C14 to C12 and C13 therefore dates the organic matter for periods back to about eight half-lives of the isotope, 45,000 years.Tags: Adult Dating, affair dating, sex dating