There are two main methods determining a fossils age, relative dating and absolute dating.
Absolute dating is used to determine a precise age of a fossil by using radiometric dating to measure the decay of isotopes, either within the fossil or more often the rocks associated with it.
The majority of the time fossils are dated using relative dating techniques.
Hutton viewed tilted strata as having been initially deposited horizontally, and then were subsequently deformed (tilted and folded) by the forces of Earth's internal heat engine.
Long before geologists tried to quantify the age of the Earth they developed techniques to determine which geologic events preceded another, what are termed "relative age” relationships.
Relative dating is different from absolute dating in which specific dates are assigned to geologic events (we will discuss absolute dating techniques later).
(light brown) Next, fossil-rich sedimentary rocks were precipitated.This group is dedicated to providing information about the scientific method as it concerns the idea of evolution in the Creation/Evolution debate. The site provides background information about stratigraphic principles and relative time, biostratigraphy (using fossils for relative dating), and radiometric dating. (dark brown) Flat lying sedimentary rocks were eventually precipitated.The secondary rocks were thought to include interlayered basalts, which Werner thought formed by combustion of buried coal layers.Relative age-dating methods determine when an event happened compared to another event. Geologic time scale Relative age-dating involves comparing a rock layer or rock structure with other near-by layers or structures. Roadcut in Wise County showing the principle of superposition (Photograph by Stan Johnson) Flat-lying sedimentary layers from the Appalachian Plateaus province of southwestern Virginia illustrate the principle of superposition.