Answer:
Correlation
Step-by-step explanation:
Correlation simply means matching rocks or strata's of the same age. This rock units or sedimentary strata's may be matched from same region or even different continents.
In correlation the major task is to establish time equivalency of various rocks or sedimentary strata's.
In correlation of rock unit or sedimentary strata, Geologist looks at the physical continuity. For example a sedimentary strata from a region having a particular sequence of rock or sedimentary strata . That same pattern of sequence may be found in another region . With the similarity in the sequence stratigraphy ( sediment layering), Geologist can infer the similarity in age of both strata's.
Fossil contents present in different strata; if similar fossil contents found in different regions, geologist can determine the age similarities.
The first picture indicates strata correlation using fossil similarities while the second picture uses the physical continuity like lithology to correlates strata's