Relative age dating and absolute age dating
Your goal is to study the smooth, parallel layers of rock to learn how the land built up over geologic time.
Now imagine that you come upon a formation like this: What do you think of it? How can you make any conclusions about rock layers that make such a crazy arrangement?
The study of fossils and the exploration of what they tell scientists about past climates and environments on Earth can be an interesting study for students of all ages.
Teaching about Earth's history is a challenge for all teachers.
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.
Sequencing the rock layers will show students how paleontologists use fossils to give relative dates to rock strata.
Numerical dating determines the actual ages of rocks through the study of radioactive decay.
The laws of physics and chemistry that governed geologic processes in the past are the same as those that govern processes now and in the future.
The geologic timescale is a chronology (calendar) of events on Earth based on obtaining ages of past events.
The table below summarises key features: Gastrioceras listeri is a particularly good example of a ZONE fossil.
As it is free swimming it could have travelled a considerable distance.