Chat free meet online room sexy single - Biostratigraphic dating relies on
Some fossils, called index fossils, are particularly useful in correlating rocks.For a fossil to be a good index fossil, it needs to have lived during one specific time period, be easy to identify and have been abundant and found in many places. If you find ammonites in a rock in the South Island and also in a rock in the North Island, you can say that both rocks are Mesozoic.Throughout the history of life, different organisms have appeared, flourished and become extinct.
Relative dating is used to arrange geological events, and the rocks they leave behind, in a sequence.
The method of reading the order is called stratigraphy (layers of rock are called strata).
Relative dating does not provide actual numerical dates for the rocks.
Fossils are important for working out the relative ages of sedimentary rocks.
Species extinctions, often referred to as “tops,” are used as horizons of correlation.