People can accurately obtain the absolute age of the earth through isotope determination. It has been found for a long time that radioactive isotopes in rocks will automatically and gradually decay into non-radioactive daughter isotopes at a constant rate, while releasing energy. As long as the temperature, With constant pressure and other factors, people can obtain accurate values. Of course, this method also has disadvantages. When the isotope age determination is performed, it is difficult to select the sample to eliminate the effect of thermal degradation in the later stage. If the sample is weathered The nature of the rock is far from that of the parent rock, and the determined age value often cannot represent the true age of the rock formation. It can be inferred from this text:. ['Isotope determination remains the only reliable and accurate method for determining rock formation age.', 'Accurate sampling is one of the keys to obtain an accurate geological age of a region through isotope determination.', 'Isotope determination is only suitable for rock formations that have changed drastically in some geological years and therefore contain a large number of radioactive elements.', 'Human knowledge is always limited, and scientific measurements are not necessarily credible.']