Geological strata dating
Chronometric dates are given in numbers of years since or before the beginning of some calendar system. That point can be in the past, the present, or the future.
In other words, the biochemical clock that this method relies on runs at a different rate in different environments.Their bones also were frequently found in association with our human and primate ancestors.can be used to tell us whether or not the animals they were from actually lived at about the same time.Fluorine analysis is primarily used for verifying whether or not two fossils in the same strata at a site were in fact contemporaneous.If not, then at least one of them must be physically out of context.With this system, an event that occurred in 1000 B.
In the past, relative dating methods often were the only ones available to paleoanthropologists.
give the time of an event with reference to another event that is not worldwide in scale.
They tell us simply that one thing is older or younger than another.
In many cases, however, it is possible to reconstruct the original sequence of strata so that they can be used for relative dating.
For instance, if we find a fossil bone below the strata 3 rock level shown above, we assume that the animal most likely lived at a time before that layer was formed.
As a result, it was difficult to chronologically compare fossils from different parts of the world.