tag:blogger.com,1999:blog-2503399848376770420.post2521299034724103051..comments2024-03-08T08:25:01.699-06:00Comments on Heresy in the Heartland: Faith, Facts, and FossilsJerihttp://www.blogger.com/profile/14097266657351609701noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-2503399848376770420.post-13407506519881524682016-01-02T16:18:09.008-06:002016-01-02T16:18:09.008-06:00I just came across your excellent article.
One sm...I just came across your excellent article.<br /><br />One small technical detail. From your discussion of Francis Collins' book you say "...three types of radioactive carbon dating yield concordant results: 4.5 billion years for Earth's oldest rocks". That doesn't seem right.<br /><br />Dating from carbon (decay of the C14 isotope) is only reliable back to about 50,000 years. This is very, very recent in geological terms. Dating of older materials uses decay of isotopes of other elements, not carbon, that have much longer half-lives. I suspect that Collins wasn't talking about carbon if his context was the age of the earth, some 4,500,000,000 years.<br /><br />(To a very, very rough approximation, radioactive dating from a given isotope can only be done to about eight or nine times its half-life. C14's half-life is about 5,730 years, so its usefulness for dating goes back about a mere 50,000 years.)<br /><br />So rather than "three types of radioactive carbon dating...", what Collins probably said was a carbon-free "three types of radioactive dating...".<br /><br />Could you check this, please? Do you have the page number from Collins' book?David Leehttps://www.blogger.com/profile/03511776786134940627noreply@blogger.com