Whats up a relative age dating activity
Students not only want to know how old a fossil is, but they want to know how that age was determined.
Some very straightforward principles are used to determine the age of fossils.
Some half lives are several billion years long, and others are as short as a ten-thousandth of a second.
After students have decided how to establish the relative age of each rock unit, they should list them under the block, from most recent at the top of the list to oldest at the bottom.It wasn't until well into the 20th century that enough information had accumulated about the rate of radioactive decay that the age of rocks and fossils in number of years could be determined through radiometric age dating.This activity on determining age of rocks and fossils is intended for 8th or 9th grade students.The teacher should tell the students that there are two basic principles used by geologists to determine the sequence of ages of rocks.They are: Principle of superposition: Younger sedimentary rocks are deposited on top of older sedimentary rocks.