Dating of fossils by scientists
So in order to date most older fossils, scientists look for layers of igneous rock or volcanic ash above and below the fossil.Scientists date igneous rock using elements that are slow to decay, such as uranium and potassium.Knowing this first: that scoffers will come in the last days, walking according to their own lusts, and saying, “Where is the promise of His coming?For since the fathers fell asleep, all things continue as they were from the beginning of creation.” For this they willfully forget: that by the word of God the heavens were of old, and the earth standing out of water and in the water, by which the world that then existed perished, being flooded with water.
This technique is widely used on recent artifacts, but educators and students alike should note that this technique will not work on older fossils (like those of the dinosaurs alleged to be millions of years old).
This evidence has indicated that radioisotopes have not decayed at a constant rate, and therefore the radiodating "clocks" in general are all broken.
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology.
But radiodating cannot proceed without some primary assumptions: the starting conditions of a given sample (e.g., how much of each isotope was present in the beginning), a steady rate of decay of certain radioactive isotopes of elements called radioisotopes, and a lack of tampering with the system (e.g., elements added or subtracted since the radioisotope "clock" first began counting time).
Then, the current amount of radioisotope is compared to the amount of stable element into which it is slowly changing. However, evidence has mounted that radioisotopes underwent a period of radical acceleration of decay in the past.
Fossils are generally found in sedimentary rock not igneous rock.