Relative dating is a dating method that used to determine determine the relative ages of geologic strata , artifacts , historical events, etc. This technique does not give specific ages to items. It only sequences the age of things or determines if something is older or younger than other things. Some types of relative dating techniques include climate chronology, dendrochronology , ice core sampling , stratigraphy , and seriation. Between the years of and , James Hutton and William Smith advanced the concept of relative dating. Hutton, a Scottish geologist, first proposed formally the fundamental principle used to classify rocks according to their relative ages.
Relative dating — Science Learning Hub
The law of superposition is that the youngest rock is always on top and the oldest rock is always on the bottom. The law of superposition is based on the common sense argument that the bottom layer had to laid down first. The bottom layer because it logically had to be laid down first must be older. The layers on top could only be laid down on top of the bottom layer so must be younger. However the relative ages of rocks is more commonly determined by the presumed ages of the fossils found in the sedimentary layers. The sedimentary layers with the simplest fossils are assumed to be older even if the sedimentary layer is found on top of a sedimentary layer that has fossils that are more complex and therefore assumed to be younger. Fossils that are in violation of the law of superposition where the older fossil occurs above a younger fossil are said to be stratigraphically disordered.
Difference Between Relative and Absolute Dating
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A method of determining the age of a fossil by comparing its placement with that of fossils in other layers of rock. Relative dating is the science determining the relative order of past events, without necessarily determining their absolute age. In geology rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another.