# How to solve radiometric dating problems

When we look at sand in an hourglass, we can estimate how much time has passed based on the amount of sand that has fallen to the bottom.Radioactive rocks offer a similar “clock.” Radioactive atoms, such as uranium (the parent isotopes), decay into stable atoms, such as lead (the daughter isotopes), at a measurable rate.These long time periods are computed by measuring the ratio of daughter to parent substance in a rock and inferring an age based on this ratio.This age is computed under the assumption that the parent substance (say, uranium) gradually decays to the daughter substance (say, lead), so the higher the ratio of lead to uranium, the older the rock must be.

Jim raised some interesting points but I don’t believe that he addressed the central points that Justin raised.

PART 1: Back to Basics PART 2: Problems with the Assumptions PART 3: Making Sense of the Patterns This three-part series will help you properly understand radiometric dating, the assumptions that lead to inaccurate dates, and the clues about what really happened in the past.

Most people think that radioactive dating has proven the earth is billions of years old.

Although the time at which any individual atom will decay cannot be forecast, the time in which any given percentage of a sample will decay can be calculated to varying degrees of accuracy.

The time that it takes for half of a sample to decay is known as the half life of the isotope.