Relative and radiometric dating
Measurements should be taken on samples from different parts of the rock body.
This helps to counter the effects of heating and squeezing, which a rock may experience in its long history.
It may be used to date a wide range of natural and man-made materials.
Fossils may be dated by taking samples of rocks from above and below the fossil's original position.
Visit the following site and read about each of Steno's laws (principles).
Keep these principles in mind as you progress through the rest of the activities in this assignment.
Elements exist in different isotopes, with each isotope of an element differing in the number of neutrons in the nucleus.
The site also provides fact sheets on the age of the Earth and isochron dating.
In Assignment 3, we began exploring the age of the Earth. Through presentation and discussion of individual ideas, the class reached agreements as to the best way to complete each of the prompts.
Radiometric dating (often called radioactive dating) is a way to find out how old something is.
The method compares the amount of a naturally occurring radioactive isotope and its decay products, in samples. It is the main way to learn the age of rocks and other geological features, including the age of the Earth itself.