Who's to say that the rocks a particular scientist is studying have not been displaced from their original positions?
In addition to the "relative" uncertainty that the geological features of an area have retained their historical integrity, there is another problem associated with relative dating.
Each original isotope, called the parent, gradually decays to form a new isotope, called the daughter.
Each isotope is identified with what is called a ‘mass number’.
From this information, scientists can accurately infer the age of the test material.
These use radioactive minerals in rocks as geological clocks.
To obtain further practice with the concepts of Steno's laws and geologic dating, work through the Understanding Geological Time section of this assignment.
This portion of the assignment is an interactive web site that allows you to apply what you have learned and to learn more about how scientists tell time with geology.
Because this assignment is linked with your work in Assignment 3, you will have "If Scientists Think. Before scientists had modern technology to assist them in their research, they had to use their power of observation to infer the relative ages of the rocks they were studying.
The process of Relative Dating was established by Nicholaus Steno in the 1600's.