The principle of radiocarbon dating is simple: the rates at which various radioactive elements decay are known, and the ratio of the radioactive element to its decay products shows how long the radioactive element has existed in the rock.
Misleading results can occur if the index fossils are incorrectly dated.
Stratigraphy and biostratigraphy can in general provide only relative dating (A was before B), which is often sufficient for studying evolution.
However, these “molecular clocks” are sometimes inaccurate and provide only approximate timing.
For example, they are not sufficiently precise and reliable for estimating when the groups that feature in the Cambrian explosion first evolved, and estimates produced by different approaches to this method may vary as well.
If a fossil is found between two layers of rock whose ages are known, the fossil’s age is thought to be between those two known ages.
Because rock sequences are not continuous, but may be broken up by faults or periods of erosion, it is difficult to match up rock beds that are not directly adjacent.Half-life of Carbon-14: Radiometric dating is a technique used to date materials such as rocks or carbon, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates.The half-life of carbon-14 is 5,730 years, so carbon dating is only relevant for dating fossils less than 60,000 years old.Strata are differentiated from each other by their different colors or compositions and are exposed in cliffs, quarries, and river banks.These rocks normally form relatively horizontal, parallel layers, with younger layers forming on top.Archaeologist Sturt Manning and colleagues have revealed variations in the radiocarbon cycle at certain periods of time, affecting frequently cited standards used in archaeological and historical research relevant to the southern Levant region, which includes Israel, southern Jordan and Egypt.