You excavate a piece of land, which is blessed by a rich collection of sedimentary rocks throughout the history of Earth.
Make a table to list the representative fossil(s) or mineral/elemental timestamps that you may find as you continue to dig down. Match the fossil to their respective geological times and estimate the age of the fossil. For practice purpose, list the full hierarchy of commonly known geological times (see page 2).
Fossils Estimated age Geological time
human stone tools
(k = kilo = 103, ya = years ago)