Carbon dating half life equation
It works because we know the fixed radioactive decay rates of uranium-238, which decays to lead-206, and for uranium-235, which decays to lead-207.So, we start out with two isotopes of uranium that are unstable and radioactive.The uranium-235 to lead-207 decay series is marked by a half-life of 704 million years.These differing rates of decay help make uranium-lead dating one of the most reliable methods of radiometric dating because they provide two different decay clocks.
As a member, you'll also get unlimited access to over 70,000 lessons in math, English, science, history, and more.They release radiation until they eventually become stable isotopes of lead.These two uranium isotopes decay at different rates. The half-life of the uranium-238 to lead-206 is 4.47 billion years.So, we rely on radiometric dating to calculate their ages.Radiometric dating, or radioactive dating as it is sometimes called, is a method used to date rocks and other objects based on the known decay rate of radioactive isotopes.This provides a built-in cross-check to more accurately determine the age of the sample.Uranium is not the only isotope that can be used to date rocks; we do see additional methods of radiometric dating based on the decay of different isotopes.Learn about half-life and how it is used in different dating methods, such as uranium-lead dating and radiocarbon dating, in this video lesson. As we age, our hair turns gray, our skin wrinkles and our gait slows.However, rocks and other objects in nature do not give off such obvious clues about how long they have been around.So, we see there are a number of different methods for dating rocks and other non-living things, but what if our sample is organic in nature?For example, how do we know that the Iceman, whose frozen body was chipped out of glacial ice in 1991, is 5,300 years old?