But Earth’s layers of rock did not give up the secret of Earth’s age easily. However, from working with layer upon layer of rock laid down on Earth over long time spans, early 20th century scientists came to believe Earth not of atoms of one chemical element into another.
Radiometric dating is self-checking, because the data (after certain preliminary calculations are made) are fitted to a straight line (an "isochron") by means of standard linear regression methods of statistics.
In this activity, students begin a sequencing activity with familiar items letters written on cards.
Once they are able to manipulate the cards into the correct sequence, they are asked to do a similar sequencing activity using fossil pictures printed on "rock layer" cards.
Despite seeming like a relatively stable place, the Earth's surface has changed dramatically over the past 4.6 billion years.
Mountains have been built and eroded, continents and oceans have moved great distances, and the Earth has fluctuated from being extremely cold and almost completely covered with ice to being very warm and ice-free.