Radioisotope Dating: The Facts and Fallacies


Radioisotope dating has been used to supposedly disprove the Bible by showing the Earth is billions of years of old, but are the assumptions for radioisotope dating valid? Do the rocks contain radiogenic materials (i.e., materials produced by radioactivity) accumulating for millions of years? I believe that radiometric dating has been shown to be greatly flawed, and all the data can be accurately interpreted within the biblical framework of a 6,000-year-old Earth.


There are different types of any one element called isotopes. Isotopes are certain types of atoms of any one element, for example, Potassium, that have a different number of neutrons. We know that Potassium (K) has nineteen protons, but each isotope has a different number of neutrons. 39K,40K, and 41K (the natural isotopes) have 20, 21, and 22 neutrons respectively. The only listed isotope of radioactive K is 40K, and is therefore called a radioisotope.

Radioisotopes decay into stable isotopes (i.e., nonradioactive). Using our example, 40K decays into stable Argon-40 (40Ar). 40K is called the parent, and 40Ar is called the daughter. The daughter is also called a radiogenic isotope since it was caused by radioactivity.

Scientists can measure the length of time it takes for half of the parent to decay into the daughter. This is called the radioactive half-life. Using statistical information, one can calculate the age of the dated specimen. However, because of certain factors, we only date igneous and metamorphic rocks,1,2,3 with a few exceptions.1,2,3

Radioisotope dating has three major assumptions, that

  1. there was little or no daughter isotope at its formation,
  2. there has been no parent or daughter coming into or out of the rock, and
  3. there has been a constant rate of decay since the rock’s initial formation.

However, there are many problems with these assumptions. The first is concerning the assumption that there was little or none of the daughter present at the rock’s formation. We mainly date igneous rocks because at their formation the high temperatures are believed to diffuse all the daughter material out of the rock.3 The problem with this assumption is that we have dated rocks of known age and found extremely old ages for rocks only a few decades old!2,3,4,5,6 Scientists have discovered that the anomalously old ages were from the daughter not being completely diffused from the lava immediately prior to its cooling, therefore having some radiogenic material from the Earth’s mantle.3

The assumption of no parent or daughter material coming into or out of the rock falls short. This is because most isotopes used in radiometric dating are easily leached out of rocks.3,5

The last assumption fails miserably. Scientists have found evidence of what is called accelerated nuclear decay. 1,6 They found radiogenic Helium (He.) in rocks that should have several orders of magnitude (powers of ten) less He if the rocks were millions or billions of years old. 1,2,3,6 Other evidence includes Polonium radiohalos and fission tracks.3,6

There are other methods we can use that produce a more accurate estimate of the Earth’s age. While they do not yield an exact age of the Earth, they do provide a maximum age limit for the Earth. For example, at present deposition rates the seafloor sediments could be deposited in a maximum twelve million years.1,3 While this is a huge problem for secular geologic models to account for, it fits nicely into the biblical framework for Earth’s history, because the Genesis Flood would have deposited vast amounts of seafloor sediments.

The Earth’s magnetic field is decaying at a measurable rate.1,3 It could only exist for a maximum of ninety million years,3 and yet here it is, and, comparatively, it is still going strong! However, another study showed that only  ten thousand years ago the magnetic field would be too strong for life.3


Radiometric dating has been shown to be greatly flawed in determining the Earth’s age. I have shown that it fails to be an accurate chronological meter, and I have shown alternative relative dating methods. All the data can be interpreted in an approximately 6,000-year-old Earth.


I thank Jay Fischer for reviewing this article and increasing the readability of this work.


1 Ross, Marcus; Whitmore, John; Gollmer, Steven; Faulkner, Danny. The Heavens and the Earth: Excursions in Earth and Space Science. Dubuque: Kendall Hunt Publishing Company, 2015.

2 Batten, Donald; Carter, Robert; Catchpoole, David; Harwood, Mark; Mason, Jim; Sarfati, Jonathan; Silvestru, Emil; Walker, Tasman. Evolutions’ Achilles’ Heels: 9 Ph. D. Scientists Explain Evolution’s Fatal Flaws — Areas Claimed to be its Greatest Strengths. Powder Springs: Creation Ministries International, 2015.

3 Snelling, Andrew. Earth’s Catastrophic Past. 2 Vols. Green Forest: Master Books; Petersburg: Answers in Genesis, 2014.

4 Morris, John; Austin, Steve. Footprints in the Ash. Green Forest, Master Books, 2009.

5 Wanser, Keith. Radioactive Decay Update: Breaking Down the Old Age Paradigm. Taped at Higher Ground Conference and Retreat Center. West Harrison: Answers Media, 2003.

6 Vardiman, Larry; Snelling, Andrew; Chaffin, Eugene. Radioisotopes and the Age of the Earth. Vol 2. Cajon: Institute for Creation Research; Chino Valley: Creation Research Society, 2005.