Non scientific methods of dating
Tests by other scientists using paleomagnetism and fission tracks confirmed the lower date.
So by 1980 there was a new, remarkably concordant date for the KBS tuff, and this became the one that was widely accepted.
Relative dating refers to non-chronometric methodologies that produce seriation based on stylistic comparison and stratigraphic assumptions.
Using new samples of feldspar and pumice they ‘reliably dated’ the tuff at 2.61 million years, which agreed nicely.
Relative dating does not provide actual numerical dates for the rocks.
Fossils are important for working out the relative ages of sedimentary rocks.
Throughout the history of life, different organisms have appeared, flourished and become extinct.
Many of these organisms have left their remains as fossils in sedimentary rocks.