What type of rock is used for relative dating joods dating
Using these key or index fossils as markers, geologists began to identify a particular layer of rock wherever it was exposed.
Because fossils are believed to record the slow but progressive development of life, geologist use them to identify the relative age of rocks throughout the world.
They quickly realized that millions of years were necessary to accumulate the rock layers we see today.
As the amount of evidence grew, scientists were able to push the age of the Earth farther and farther back in time.
Concealed within the rocks that make up the Earth's crust lies evidence of over 4.5 billion years of time.
Hutton, a Scottish geologist, first proposed formally the fundamental principle used to classify rocks according to their relative ages.The older layers are lower 'relative' to the younger layers.Long before scientists had developed the technology necessary to assign ages in terms of number of years before the present, they were able to develop a 'relative' geologic time scale.The time scale is constantly being refined, so don't be surprised to see continuing revisions as our technology and understanding of the Earth improves!The time scale on the right shows the subdivisions of geologic time in a form that will fit on a single page.