Seriation uses the assumption that once a tool was developed, its use would become more widespread.

Radiometric dating, based on known rates of decay of radioactive isotopes in objects, allows a specific age of an object to be determined to some degree of accuracy.

Estimates of the absolute age of prehistoric and geological events and remains amounted to little more than inspired guesswork, as there was no scientific basis for testing such proposals.” With this background, it is strange that the “standard geologic column” that identifies the rock strata on the earth and assigns very old ages to those strata was developed by Sir Charles Lyell in 1830.

This was done 100 years before absolute dating methods were available.

The radiometric techniques that give absolute dating estimates are based on radioactive decay of elements such as uranium. Looking at how rock formations are structured, a geologist may be able to say which rock was developed in which layer in a particular order but not be able to determine that actual geologic age of the layers. Relative dispersion, sometimes called the coefficient of variation, is the result of dividing the st. by the mean, hence it is dimensionless (it may also be presented as a percentage).

Geologists also have radiometric methods for absolute dating based on radioactive decay of certain elements. So a low value of relative dispersion usually implies that the st. is small in comparison to the magnitude of the mean, as in a st. of 6cm for a mean of 4m would give a figure of 0.015 (1.5%) whereas with a mean of 40cm it would be 0.15 or 15%. However with measurements either side of zero and a mean close to zero the relative dispersion could be greater than 1.