The overlap of species extinctions and inceptions allows the development of range zones (see figure below), which can be correlated from site to site.
A biostratigraphic zone is a body of rock defined or characterized by its fossil content.
Figure 1 shows how the overlap of species' ranges (between inception and extinction) is used to define zones.
In the field of Geology, dating is an important term as it is a technique through which evaluation regarding the age and period about the fossil, remains, the archaeologists do valuables and artifacts.
At first, there were not many methods of dating were available, but now with advancement in the technology, we mainly have two types of techniques to ascertain ages of ancient belongings.
In other words, we can say that in relative dating the archaeologist determines that which of the two fossil or the artifacts are older.
Contrary to this, absolute dating is the technique, using which the exact age of the artifacts, fossils, or sites are ascertained.
Relative dating is a less advanced technique as compared to absolute dating.