This principle presumes that the oldest layer of a stratigraphic sequence will be on the bottom and the most recent, or youngest, will be on the top.
The Scottish geologist James Hutton (1726-1797) argued that granite and basalt by solidification within the earth (as opposed to precipitating in from oceanwater).
Relative dating methods allow one to determine if an object is earlier than, later than, or contemporary with some other object.
It does not, however, allow one to independently assign an accurate estimation of the age of an object as expressed in years.
This also works with stone tools which are found abundantly at different sites and across long periods of time.
Stratigraphic dating is based on the principle of depositional superposition of layers of sediments called strata.