Learn how scientists determine the ages of rocks and fossils.
The most common form of relative dating is called stratigraphic succession.
This is just a fancy term for the way rock layers are built up and changed by geologic processes.
The first method that scientists use to determine the age of rocks is relative dating.
In this method, scientists compare different layers of rock to determine an ordered sequence of events in geologic history.
If I told you that I was 30 years old, that number would be my numerical age.
If I told you I was 32 years younger than my mother, that number would be my relative age.
He could be pretty confident that his super awesome dinosaur was about 175 million years old.
Stratigraphic and fossil succession are good tools for studying the relative dates of events in Earth's history, but they do not help with numerical dating.
Scientists know that the layers they see in sedimentary rock were built up in a certain order, from bottom to top.