This means that a quartz sandstone deposited 500 million years ago will look very similar to a quartz sandstone deposited 50 years ago.
Relative time can not determine the actual year a material was deposited or how long deposition lasted; it simply tell us which events came first.
Examples include fractures, faults, and igneous intrusions.
Igneous intrusions are sometimes referred to as a seperate principle, the Hutton’s theory of uniformatarianism and the principles of stratigraphy would be fully developed and made popular by another Scottish geologist Charles Lyell (1797-1875) with his classic three volume work, first published from 1830 to 1833, entitled The science of stratigraphy changed humans’ view of the world from one, which was static to one that was dynamic and changing.
Unlike relative time, absolute time assigns specific ages to events or formations and is typically recorded in years before present.
This process requires much more sophisticated chemical analysis and, although other processes have been developed, often utilizes the decay rates of radioactive isotopes to determine the age of a given material.
Relative dating uses the principles or laws of stratigraphy to order sequences of rock strata.