Absolute dating ppt
By modern scientific calculations, the earth is many millions of years old.
The Absolute Geologic Time Scale has been developed by using a process called “Isotopic Dating”, in which the decay rates of certain radioactive materials are established and measured, then used as “clocks” to calculate the ages of various rocks.
These rocks are tilted due to deposition on the non-horizontal surfaces of primitive rocks.
is a way to use geometric relationships between rock bodies to determine the sequence of geologic events in an area.
Relative dating is different from absolute dating in which specific dates are assigned to geologic events (we will discuss absolute dating techniques later).
The Geologic Time Scale is illustrated here to help you see the way geologists have broken down geologic time into sections, each with an interesting and fascinating name, and each containing a package of rocks deposited during a certain time period…over the world.
The scale shows how old certain rocks are in millions of years. You will see the Jurassic rocks were deposited about 138-205 million years ago.