How is radiometric dating used to find the age of sedimentary rock
Radioactive elements decay at a certain constant rate and this is the basis of radiometric dating. But, the decay elements need to be set, much like you would re-set a stop watch for a runner, to ensure an accurate measurement. When minerals get subducted into the Earth and come back as volcanic magmas or ash, this essential re-sets the radiometric clock back to zero and therefore a reliable age date is possible. Sedimentary rocks may have radioactive elements in them, but they have been re-worked from other rocks, so essentially, there radiometric clock has not been re-set back to zero.
Why is it difficult to date sedimentary rocks using radiometric dating techniques?
Why is it difficult to date sedimentary rocks using radiometric dating techniques? | Socratic
Android App. New to truMingle? Join for free! Forgot your password? Remember me. This is because siliciclastic rocks are a deposition of sediment that has been lithified. There are certain kinds of atoms in nature that are unstable and spontaneously change decay into other kinds of atoms.
Why can't radioactive dating be used to date sedimentary rock?
Sedimentary rock is composed of the weathered remains of a variety of rocks of all ages. It would therefore only be possible to date specific components of a sample, none of which would equate to the age of the sedimentary rock as a unit. Sedimentary rock is dated by its association in the geologic column with igneous and metamorphic rock which can be dated by radioactive dating techniques. They are called sedimentary rocks.
The most widely known form of radiometric dating is carbon dating. This is what archaeologists use to determine the age of human-made artifacts. But carbon dating won't work on dinosaur bones. The half-life of carbon is only 5, years, so carbon dating is only effective on samples that are less than 50, years old. Dinosaur bones, on the other hand, are millions of years old -- some fossils are billions of years old.