In my experience, one of the most persuasive scientific claims for a young Earth is the detection of carbon-14 in geological samples such as coal and fossilized dinosaur remains.1 According to young-earth creationists (YECs), if the coal samples and fossils are truly millions of years old (as the scientific community claims), then there shouldn’t be any trace of carbon-14 in these samples. Why? It’s because the half-life of carbon-14 is about 5,700 years, meaning that all the detectable carbon-14 should have disappeared from the samples long before they reach even 100,000 years of age. 

In Dinosaur Blood and the Age of the Earth, I respond to this young-earth argument, suggesting three mechanisms that can account for carbon-14 in fossil remains (and by extension, in geological materials) from an old-earth perspective.

When YECs detect carbon-14, they find it at low levels, corresponding to age dates older than 30,000 years (not 3,000 to 6,000 years old, as their model predicts, by the way). These low levels make it reasonable to think that some of the carbon-14 signal comes from contamination of the sample by, say, microorganisms picked up from the environment.

These low levels also make it conceivable that some of the detected carbon-14 is due to a ubiquitous carbon-14 background. Cosmic rays are continuously producing radiocarbon from nitrogen-14. Because of this nonstop production, carbon-14 is everywhere and will show up at extremely low levels in any measurement that is made, even if it isn’t present in the actual sample.

It is also possible that some of the carbon-14 in the fossil and coal samples arises from the in situ conversion of nitrogen-14 to carbon-14 driven by the decay of radioactive elements in the environment. Because fossils and coal derive from once-living organisms, there will be plenty of nitrogen-14 contained in these specimens. For example, environmental uranium and thorium would readily infuse into the interiors of fossils, and as these elements decay, the high energy they release will convert nitrogen-14 to carbon-14.

Employing a “back-of-the-envelope” flux analysis, Vernon Cupps—a YEC affiliated with the Institute of Creation Research—has challenged my assessment, concluding that neither (1) the production of carbon-14 from cosmic radiation nor (2) the decay of radioactive isotopes in the environment is sufficient to account for the carbon-14 detected in fossil and geological samples.2

Though I think his analysis may be unrealistically simplistic, let’s assume Cupps’s calculations are correct. He still misses my point. In Dinosaur Blood and the Age of the Earth, I argue that all three possible sources simultaneously contribute to the detectable carbon-14. In other words, while no single source may fully account for the detectable carbon-14, when combined, all three can.  Cupps’s analysis neglects the contribution of the ubiquitous background carbon-14 and possible sources of contamination from the environment.

Ironically, the low levels of carbon-14 detected in fossils and geological specimens by YECs actually argue against a young Earth, not an old Earth.

How can that be?

If fossil and geological specimens are between 3,000 and 6,000 years old, then somewhere between 50 and 75 percent of the original carbon-14 should remain in the sample. This amount of material should generate a strong carbon-14 signal. The fact that these specimens all age-date to 30,000 to 45,000 years old means that less than 2 percent of the original carbon-14 remains in these samples—if the results of this measurement are taken at face value. It becomes difficult to explain this result if these samples are less than 6,000 years old. On the other hand, the weak carbon-14 signal measured by YECs does make sense if carbon-14 does not reflect the material originally in the sample, but instead stems from a combination of (1) contamination from the environment, (2) ubiquitous background radiocarbon, and/or (3) irradiation of the samples by isotopes such as uranium or thorium in the environment.

To put it plainly, it is difficult to reconcile the carbon-14 measurements made by YECs with fossil and geological samples that are 3,000 to 6,000 years old, Cupps’s analysis notwithstanding.

On the other hand, an old-earth perspective has the explanatory power to account for the low levels of carbon-14 associated with fossils and other geological samples.

Resources

Endnotes

  1. Vernon R. Cupps, “Radiocarbon Dating Can’t Prove an Old Earth,” Acts & Facts, April 2017, http://www.icr.org/article/9937.
  2. Ibid.

Subjects: Age of the Earth, Young-Earth Creationism

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About The Author

Kenneth R. Samples

I believe deeply that "all truth is God’s truth." That historic affirmation means that when we discover and grasp truth in the world and in life we move closer to its divine Author. This approach relies on the Christian idea of God’s two revelatory books - the metaphorical book of nature and the literal book of Scripture. As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. My writings and lectures at RTB focus on showing how the great doctrinal truths of the faith (the Trinity, the Incarnation, the Atonement, creation ex nihilo, salvation by grace, etc.) are uniquely compatible with reason. This approach reflects the historic Christian apologetics statement - "faith seeking understanding." I work to help myself and others fulfill Peter's words in 2 Peter 3:18: "But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen." As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. • Biography • Resources • Upcoming Events • Promotional Items Kenneth Richard Samples began voraciously studying Christian philosophy and theology when his thirst for purpose found relief in the Bible. He earned his undergraduate degree in philosophy and social science from Concordia University and his MA in theological studies from Talbot School of Theology. For seven years, Kenneth worked as Senior Research Consultant and Correspondence Editor at the Christian Research Institute (CRI) and regularly cohosted the popular call-in radio program, The Bible Answer Man, with Dr. Walter Martin. As a youth, Kenneth wrestled with "unsettling feelings of meaninglessness and boredom," driving him to seek answers to life's big questions. An encounter with Christian philosophy in Mere Christianity by C. S. Lewis led Kenneth to examine the New Testament and "finally believe that Jesus Christ is the divine Son of God, the Lord and Savior of the world." From then on, he pursued an intellectually satisfying faith. Today, as senior research scholar at Reasons to Believe (RTB), Kenneth uses what he's learned to help others find the answers to life's questions. He encourages believers to develop a logically defensible faith and challenges skeptics to engage Christianity at a philosophical level. He is the author of Without a Doubt and A World of Difference, and has contributed to numerous other books, including: Lights in the Sky and Little Green Men, The Cult of the Virgin, and Prophets of the Apocalypse. He has written articles for Christianity Today and The Christian Research Journal, and regularly participates in RTB's podcasts, including Straight Thinking, a podcast dedicated to encouraging Christians to utilize sound reasoning in their apologetics. He also writes for the ministry's daily blog, Today’s New Reason to Believe. An avid speaker and debater, Kenneth has appeared on numerous radio programs such as Voice America Radio, Newsmakers, The Frank Pastore Show, Stand to Reason, White Horse Inn, Talk New York, and Issues Etc., as well as participated in debates and dialogues on topics relating to Christian doctrine and apologetics. He currently lectures for the Master of Arts program in Christian Apologetics at Biola University. Kenneth also teaches adult classes at Christ Reformed Church in Southern California. Over the years Kenneth has held memberships in the American Philosophical Association, the Evangelical Philosophical Society, the Evangelical Theological Society, and the Evangelical Press Association. The son of a decorated World War II veteran, Kenneth is an enthusiastic student of American history, particularly the Civil War and WWII. His favorite Christian thinkers include Athanasius, Augustine, Pascal, and C. S. Lewis. He greatly enjoys the music of the Beatles and is a die-hard Los Angeles Lakers fan. Kenneth lives in Southern California with his wife, Joan, and their three children.



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