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.
However, we must be careful to note whether or not the fossil comes from the mixed strata zone of the filled in hole..
However, relative methods are , which is that if there are layers of deposits, those laid down first will be on the bottom and those laid down last will be on the top. However, geological strata are not always found to be in a neat chronological order.
Presumably if all the world’s outcrops were integrated, sediments representing all of geologic time would be available for examination.
This optimistic hope, however, must be tempered by the realization that much of the record—older than 541 million years—is missing.
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Correlating two separated outcrops means establishing that they share certain characteristics indicative of contemporary formation.
The most useful indication of time equivalence is similar fossil content, provided of course that such remains are present.
Dating techniques are procedures used by scientists to determine the age of an object or a series of events.
The two main types of dating methods are relative and absolute.
These processes result in All of these processes confuse the stratigraphic record.
In many cases, however, it is possible to reconstruct the original sequence of strata so that they can be used for relative dating.
is, as mentioned earlier, the technique of piecing together the informational content of separated outcrops.