Methods of dating rock layers
In such cases subjective element cannot be ruled out.
But, for a single culture site the method is quite reliable.
The Age of Dinosaurs was so many millions of years ago that it is very difficult to date exactly.
Scientists use two kinds of dating techniques to work out the age of rocks and fossils. This considers the positions of the different rocks in sequence (in relation to each other) and the different types of fossil that are found in them.
This is because new sediments are always laid down on top of sediments that have already been deposited.
For example if you have a fossil trilobite and it was found in the Wheeler Formation.The deposit thus occurring forms layers depending on the nature of the material brought in by the people inhabiting the area.According to this method, the upper deposits are younger and the lower deposits are older.Sometimes, scientists already know the age of the fossil because fossils of the same species have been found elsewhere and it has been possible to establish accurately from those when the dinosaur lived.Geologists call this the principle of lateral continuity.
Current understanding of the history of life is probably close to the truth because it is based on repeated and careful testing and consideration of data.