herpes dating site toronto - Dating rock strata
This information has also helped determine the age of the Earth itself.
Dating rock strata video
To determine the ages of these specimens, scientists need an isotope with a very long half-life.
Some of the isotopes used for this purpose are uranium-238, uranium-235 and potassium-40, each of which has a half-life of more than a million years.
This is what archaeologists use to determine the age of human-made artifacts. The half-life of carbon-14 is only 5,730 years, so carbon-14 dating is only effective on samples that are less than 50,000 years old.
Dinosaur bones, on the other hand, are millions of years old -- some fossils are billions of years old.
Although most would be called "progressive creationists" in today's terminology, they would not be pleased to see all the evolutionary baggage that has been loaded onto their classification of strata.
The geologic column was not composed by assembling a chronology of "periods," "eras" or other supposed measures of time, but by superposition of objectively defined sequences of sedimentary strata called "systems." The "periods" and "eras" were later appended to the system nomenclature of the "geologic Column" transforming it into a "geologic time scale." The notion that the earth's crust has on "onion skin" structure with successive layers containing all strata systems distributed on a global scale is not according to the facts.
Fossils can't form in the igneous rock that usually does contain the isotopes.
The extreme temperatures of the magma would just destroy the bones.
Since the moon and the Earth probably formed at the same time, this supports the current idea of the Earth's age.
You can learn more about fossils, dinosaurs, radiometric dating and related topics by reading through the links on the next page.
Based on the analysis of these samples, scientists estimate that the Earth itself is about 4.5 billion years old.