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Four radioisotopes commonly used radiometric dating

These basalts yield ages of up to 1 million years based on the amounts of potassium and argon isotopes in the rocks.But when we date the rocks using the rubidium and strontium isotopes, we get an age of 1.143 billion years.

Obviously, these eruptions took place very recently, after the Canyon’s layers were deposited ().Because of such contamination, the less than 50-year-old lava flows at Mt.Ngauruhoe, New Zealand (), yield a rubidium-strontium “age” of 133 million years, a samarium-neodymium “age” of 197 million years, and a uranium-lead “age” of 3.908 billion years!Part 2 explains how scientists run into problems when they make assumptions about what happened .An hourglass is a helpful analogy to explain how geologists calculate the ages of rocks.Yet this view is based on a misunderstanding of how radiometric dating works.

Part 1 (in the previous issue) explained how scientists observe unstable atoms changing into stable atoms in the present.

Yet the same uranium decay also produced abundant helium, but only 6,000 years worth of that helium was found to have leaked out of the tiny crystals. Not Billions (Master Books, Green Forest, Arkansas, 2005), pages 65–78.

This means that the uranium must have decayed very rapidly over the same 6,000 years that the helium was leaking. The assumptions on which the radioactive dating is based are not only unprovable but plagued with problems.

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.

For example, with regard to the volcanic lavas that erupted, flowed, and cooled to form rocks in the unobserved past, evolutionary geologists simply assume that none of the daughter argon-40 atoms was in the lava rocks.