Second, it is possible to determine the numerical age for fossils or earth materials.
Numerical ages estimate the date of a geological event and can sometimes reveal quite precisely when a fossil species existed in time.
The same thing can be done with geologic features in a rock outcrop.
To do this geologists use the Laws of Relative Dating.
The layers of rock at the base of the canyon were deposited first, and are thus older than the layers of rock exposed at the top (principle of superposition).
In the Grand Canyon, the layers of strata are nearly horizontal.
Most sediment is either laid down horizontally in bodies of water like the oceans, or on land on the margins of streams and rivers.
Nemo is the oldest, followed by Twilight, Hunger Games, and the Avengers Again, we have not stated anything about the actual age of these movies, we've just put them in order relative to one another.
Often when geologists examine rock outcrops like the one illustrated above they are interested in not only the types of rocks present, but the order in which they formed.
When they put events in chronological order like they use Relative Dating.
We do this all the time in our regular day to day lives.
For example, lets put the following movies in order of relative age from oldest to youngest: Twilight, Finding Nemo, the Avengers, the Hunger Games.
However, the age of each fossil primate needs to be determined so that fossils of the same age found in different parts of the world and fossils of different ages can be compared.