Relative dating cannot establish absolute age, but it can establish whether one rock is older or younger than another.
Relative dating requires an extensive knowledge of stratigraphic succession, a fancy term for the way rock strata are built up and changed by geologic processes.
This means that a quartz sandstone deposited 500 million years ago will look very similar to a quartz sandstone deposited 50 years ago.
Making this processes even more difficult is the fact that due to plate tectonics some rock layers have been uplifted into mountains and eroded while others have subsided to form basins and be buried by younger sediments.
Ice cores showed the age of a military plane buried in the artic as thousands of years old.
Similarly, dendrochronology measures the tree rings in trees and assumes they represent years.
Some types of relative dating techniques include climate chronology, dendrochronology, ice core sampling, stratigraphy, and seriation.
ANSWER: Relative dating is used to determine the relative ages of geologic strata, artifacts, historical events, etc.
This technique does not give specific ages to items.
The most obvious feature of sedimentary rock is its layering.
This feature is produced by changes in deposition over time.