Extinct nuclide dating
Wiens has a Ph D in Physics, with a minor in Geology.
When the glass is turned over, sand runs from the top to the bottom.
Radioactive atoms are like individual grains of sand--radioactive decays are like the falling of grains from the top to the bottom of the glass.
This paper describes in relatively simple terms how a number of the dating techniques work, how accurately the half-lives of the radioactive elements and the rock dates themselves are known, and how dates are checked with one another.
In the process the paper refutes a number of misconceptions prevalent among Christians today.
He was employed at Caltech's Division of Geological & Planetary Sciences at the time of writing the first edition.