Some of the basic Dating Methods are as follows:
- Samarium - Neodymium. (Sm-Nd)
- Rhenium - Osmium (Re-Os)
- Uranium / Thorium - Lead. ( U/Th-Pb)
- Ribidium - Strontium (Rb-Sr)
- Potassium - Argon (K-Ar)
- Argon - Argon (Ar-Ar)
- Lutetium - Hafnium (Lu-Hf)
- Constant decay rate.
- No gain or loss of parent or daughter isotope.
- Known amounts of daughter isotope at start.
A shift from contamination can take place in all of the data points, but such contamination does not affect all data points equally, so it can cause the data points to shift off the true Isochron completely. Given this when one looks at an Isochron plot how can one really tell where the true Isochron line should be. Sufficient contamination can produce any Isochron pattern regardless of the true Isochron. It is even possible to get a negative slope, this would be equivalent to a negative or future date.
When you look at actual isochron plots such as the ones at above link, there seems to be room for subjectivity. Some are better than others but there is often room for multiple plot lines. Even uniformitarian geologists recognize the existence of false isochron. So how do they distinguish good data from bad? The answer is where the sample fits in the Geologic Column.
The unique key assumption of Isochron dating is that the affect of contamination does on the Isochron can be determined. However the quality of an Isochron is still judged by where the sample fits in the Geologic Column. Also like all forms of radiometric dating it assumes that nuclear decay rates are constant, an assumption which will later be shown false.
This email is free from viruses and malware because avast! Antivirus protection is active.