n. (Archaeology) any method of dating material based on the decay of its constituent radioactive atoms, such as potassium-argon dating or rubidium-strontium dating. Also called: radioactive dating.

What is meant by stratigraphy?

Stratigraphy, scientific discipline concerned with the description of rock successions and their interpretation in terms of a general time scale. It provides a basis for historical geology, and its principles and methods have found application in such fields as petroleum geology and archaeology.

What does irretrievable mean?

: not retrievable : impossible to regain or recover.