Published: 03.22.2021.
The first article of this series about radioactive dating techniques will be about the most famous of them: carbon dating.
The basics
For many elements, there exist different isotopes: atoms which have the same number of protons in the nucleus, so they behave the same way chemically, but have a different number of neutrons. The total number of protons and neutrons is denoted as a number after or before the name of the isotope. For instance, carbon-14 has 6 protons and 8 neutrons.
There are three isotopes of carbon found in nature: carbon-12, carbon-13 and carbon-14. They make up about 99%, 1% and 0.000000000001% of carbon in nature, respectively. Carbon-14 (C-14) is radioactive, with a half-life of around 5730 years. It is created when the cosmic rays from the sun create neutrons in the atmosphere. Those neutrons then strike atoms of nitrogen (nitrogen-14) in the atmosphere and unite with them, while the atom loses a proton. Since C-14 is unstable, it then begins to decay back into nitrogen, whereby one of the neutrons is converted into a proton, while emitting an electron and an electron antineutrino as beta radiation.1
Radiocarbon dating works the following way in theory: plants absorb CO2 with all the different carbon isotopes into their body to make carbohydrates, building up their organisms. Animals eat the plants and so incorporate a small amount of radioactive carbon into their bodies. When they die, they stop taking up radiocarbon and so what was in their bodies at their death begins to decay. If the scientists measure this radiocarbon, they can determine when the organism died, by comparing it to the amount of radiocarbon in the atmosphere now, accounting for the increased levels in the air because of nuclear tests in the 20th century.2
Measuring radiocarbon
C-14 is usually measured with an instrument called an accelerator mass spectrometer (AMS).
The amount of radiocarbon in a sample can be given as percent of modern carbon (pMC or pmc), that is as the percent of the modern atmospheric amount (of the year 1950). The radiocarbon date can usually be given as years before present. The conversion formula between pmc and the actual age is pmc = 100 × 2–t/5730, t being the age in years.3 One can also use the Libby half-life (5568 years) for an uncalibrated date, in order to keep the measures standardized over the decades, as more and more accurate half-lives are determined.4
The assumptions
Like any other radioactive dating technique, radiocarbon dating relies on some basic assumptions5:
1. C-14 was always created at the same speed as it decayed (equilibrium of C-14 on Earth).
2. The C-14 always decayed with the same speed.
3. The percentage of C-14 in the atmosphere was the same in the past, as it is now.
4. Nothing has ever contaminated the sample with more C-14, and didn’t remove any of it either.
All of these assumptions are unproven. However, if any of these are false, they could upset any given carbon date.
Some considerations
Assumption No. 1 requires the amount of radiocarbon created in the atmosphere to be equal to the amount lost in decay, in other words, they should be in equilibrium. The C-14 atoms are created because the solar rays hit nitrogen atoms. The amount of solar rays reaching the Earth is dependent on the strength of the Earth’s magnetic field. The Earth’s magnetic field has been weakening significantly in every measurement since the German scientist Karl Friedrich Gauss measured it in 1832.6 Since that time, its strength has decayed exponentially, by about five percent every decade.7 If the Earth is just a few thousand years old, then during the time when the Earth’s magnetic field was stronger, fewer solar wind particles hit the earth, thus creating fewer C-14 Atoms. If the organism absorbed less C-14 during its lifetime, it has less C-14 to decay, resulting in older ages. A change in the Earth’s magnetic field can upset carbon dating.
Anomalies
As mentioned above, the AMS is very precise, but it has limits: if something is over 100,000 years old, it’s radiocarbon dead, meaning, that the instrument can’t detect C-14 atoms in the sample anymore. However, there are many allegedly very old samples, where radiocarbon has been detected, including coal, wood and marble. The amount of C-14 in these samples was between 0.01 to 0.71 pmc, making them around 40,900 to 76,140 years old using the standard assumptions. This research is published in regular research journals, which treat all of these measurements as the result of “contamination”, either on site or in the measuring instrument. However, scientists consistently get such results, even after pre-treating the samples to remove possible contamination. You can read about some of these results in “Measurable 14C in Fossilized Organic Materials: Confirming the Young Earth Creation-Flood Model” published by the Institute of Creation Research (ICR).8
The ICR in the RATE project (Radioisotopes and the Age of the Earth) also sent diamonds into a lab to be carbon-dated. Diamonds are supposed to be hundreds of millions, or billions of years old according to evolutionary theory. The scientists sent multiple small diamonds to a lab to test them for C-14. The results they got were very interesting. All of the diamond samples contained C-14 significantly above the laboratory background level. This would make them, using the standard assumptions, about 55,700 years old. John R. Baumgardner PhD, writes in “14C Evidence for a Recent Global Flood and a Young Earth”: “[o]ur 14C RATE project has measured 14C/C ratios above the AMS threshold in diamonds from a variety of locations. Although more confirmation is needed to justify a strong claim in this regard, these measurements appear to limit the age of the physical earth itself to the range of thousands (as opposed to billions) of years.”9
Conclusion
Carbon dating is of limited usefulness, just like other radioactive dating techniques, due to its many unknowns. However, even things, which in the evolutionary timescale ought to be without detectable radiocarbon, like many coal from coal mines, diamonds and fossils, contain radiocarbon. This points to a much younger age for those samples.
Further resources
https://answersingenesis.org/geology/carbon-14/
https://answersingenesis.org/geology/carbon-14/carbon-14-in-fossils-and-diamonds/
https://answersingenesis.org/geology/carbon-14/a-creationist-puzzle/
https://www.icr.org/article/carbon-14-found-dinosaur-fossils
https://www.icr.org/article/rethinking-carbon-14-dating-what-does
https://creation.com/c14-equilibrium-in-the-atmosphere-and-dinosaur-soft-tissue
https://creation.com/diamonds-a-creationists-best-friend
References
1: https://en.wikipedia.org/wiki/Carbon-14 . Accessed on 01.21.2021.
2: https://en.wikipedia.org/wiki/Radiocarbon_dating . Accessed on 01.12.2021.
3: http://static.icr.org/i/pdf/technical/Measurable-14C-in-Fossilized-Organic-Materials.pdf . Accessed on 01.25.2021.
An online log-2 calculator: https://miniwebtool.com/log-base-2-calculator
further data: http://www.radiocarbon.com/PDF/Beta-AMS-Methodology.pdf . Accessed on 03.05.2021.
4: same as 2
5: https://answersingenesis.org/geology/carbon-14/a-creationist-puzzle/ . Accessed on 01.10.2021.
6: https://en.wikipedia.org/wiki/Earth%27s_magnetic_field . Accessed on 03.05.2021.
7: https://www.ctvnews.ca/sci-tech/the-earth-s-magnetic-field-is-weakening-and-scientists-don-t-know-why-1.4986480#:~:text=Data . Accessed on 03.04.2021.
8: http://static.icr.org/i/pdf/technical/Measurable-14C-in-Fossilized-Organic-Materials.pdf . Accessed on 01.25.2021.
9: https://www.globalflood.org/uploads/1/0/4/4/10444187/c-14_evidence_for_young-earth_rate_chapter_2005.pdf . Accessed on 03.04.2021.