You could start with https://en.wikipedia.org/wiki/Stratigraphy https://en.wikipedia.org/wiki/Stratigraphy and go from there. For the upper bound: https://en.w

You could start with https://en.wikipedia.org/wiki/Stratigraphy https://en.wikipedia.org/wiki/Stratigraphy and go from there. For the upper bound: https://en.wikipedia.org/wiki/Clair_Cameron_Patterson#Measurement_of_the_Earth's_age https://en.wikipedia.org/wiki/Clair_Cameron_Patterson#Measur...