Does Radiometric Dating Prove Millions of Years?
Introduction
As we saw in our last post, the idea that the rock layers are millions of years old is mostly based on the assumption of uniformitarianism. Geologists assume that the same forces observed on the earth today are responsible for shaping the earth in the past. So they conclude that the rock layers must be millions (even billions) of years old, put down by very slow and gradual deposition. But believe it or not, other than this assumption, there is little reason to believe the rock layers are that old.
That said, those who hold to the evolutionary timescale will point to rock dating methods as proof of millions of years. But are these methods reliable?
The short answer is no. Radioisotope dating, also called radiometric dating, often yields incorrect and conflicting results. This is probably because of the unprovable assumptions required for the calculations. As a result, they are not the infallible techniques that many people think they are.
How Does Radiometric Dating Work?
No one can measure the age of a rock. Instead, scientists measure chemicals in the rock, and then estimate an age from there by doing some calculations. Radiometric dating is commonly used to date igneous rocks, which form when hot molten material cools and solidifies. The dating would be how long ago the rock hardened from the molten state.
These rocks will typically contain radioactive elements that are in the process of changing into other elements. There are many of these that geologists will look at. For example, Uranium-238 decays into Lead-206, and Potassium-40 decays into Argon-40. For samples of once living material, such as a bone, scientists will use Carbon-14 which decays into Nitrogen-14. The principles are similar, and in this case, the dating would be how long ago the organism died.
Decay rates are given in half-life, which is the time that it takes for a parent element to decay into half of its original amount. For some elements, the half-life can be in the millions or billions of years. The half-life of Uranium-238 is 4.47 billion years. The half-life of Carbon-14 is 5,700 years.
An hourglass is a good illustration of how the calculations work. The sand at the top is the parent element, and the sand at the bottom is the daughter element. Scientists can very accurately measure the ratio between parent and daughter elements in a rock. So, if they know the decay rate, theoretically they can calculate how long ago there was only parent material present in the rock. That is, when all the sand was at the top of the hourglass.
Three Unprovable Assumptions
A major problem is that the calculation from the parent/daughter ratio to a date or age in years relies on three unprovable assumptions:
- The amount of parent and daughter material is known at the start.
- The decay rate has always been the same as what is measured in the lab today.
- There has been no addition or loss of either parent or daughter material from outside the sample.
We now know that there are problems with each one of these assumptions.
For example, it is quite possible that decay rates were much higher in the past.[1] And considering that half-lives can be in the billions of years, then just a very little extra daughter material in the bottom of the hourglass will make a huge difference and cause a rock to appear much older than it is. Another likely issue is that assumptions concerning the starting ratios can be wrong.[2] It’s probably wrong to assume that there was no daughter element present at all at the start of the process. And this will vary case by case as well.
Highly qualified scientists have been researching these issues for years and the field is very technical. But for those who are interested, the information is available.[3] However, all we really need to do is look at some of the results of radiometric dating to understand the magnitude of its problems.
Let’s consider just a few examples of wrong and conflicting dates.
Wrong Dates for Rocks of Known Ages
Very often when young rocks of known ages are dated, the results will be wrong by hundreds of thousands and even millions of years.
One example is the potassium-argon dating of five different lava flows from Mt. Ngauruhoe in New Zealand. One lava flow occurred in 1949, three in 1954, and one in 1975. Eight samples from all the flows were tested, with resulting dates ranging from less than 270 thousand, up to 3.5 million years ago.[4] In this case, it is likely that excess Argon was retained in the magma after solidification.
As another example, a rock sample was taken from the newly formed 1986 lava dome at Mt. St. Helens in Washington state. First, the whole rock was tested. Then, measurements were taken on four different minerals in the rock. Five different results from the five tests came back, ranging from 340 thousand to 2.8 million years, when the samples were just 10 years old.[5]
Conflicting Dates for Rocks of Unknown Ages
Very often samples of unknown ages are tested with conflicting results that are clearly problematic.
Geologist Dr. Steve Austin sampled basalt at the bottom of the Grand Canyon, and also lava that spilled over the edge of the canyon at the top. According to secular geology, the lava at the top should be about a billion years younger than the basalt at the bottom. However, the rubidium-strontium method suggested that the lava flow at the top was 270 million years older than the basalt at the bottom of the canyon.[6] This would be impossible.
Continuing his investigation, Austin tested the basalt rock using three other methods. Six tests using the potassium-argon method came in at between 10 thousand to 117 million years. The rubidium-strontium isochron method came in at 1.34 billion years, and the lead-lead isochron method at 2.6 billion years.[7] This is a range of error in the billions of years!
In Australia, wood found in some Tertiary basalt was clearly buried in the lava flow that formed the basalt. The wood was dated by Carbon-14 analysis at about 45,000 years, but the basalt was dated at 45 million years old. This clearly can’t be. They should be about the same age.[8]
Diamonds are routinely Carbon dated at about 50 thousand years old. But according to uniformitarian geology, diamonds are supposed to be between 1 and 3 billion years old.[9]
Conclusion
We have abundant evidence that something is really wrong with radiometric dating. People don’t know that these methods produce errors in the billions of years for rocks of known ages; and variation in the millions and billions of years for rocks of unknown ages.
If we can’t trust the test results from rocks of known ages, then how can we trust the results from rocks of unknown ages? We can’t. The truth is, radiometric dating is highly unreliable. At best, it gives only very rough estimates. At worst, it is basically useless. Either way, radiometric dating does not prove millions of years.
If radiometric dating is not proof, then all we really have left, once again, are starting assumptions. And we find that there is very little reason to believe the rock layers are millions of years old. In fact, we find a lot of evidence that fits the Biblical timeline of thousands of years, very nicely. In other words, there’s nothing wrong with believing Genesis for what it appears to say, when we read it in a straightforward way.
I know that’s a pretty bold claim. So, we’ll look at some of that evidence in our next post.
[1] Ken Ham and Bodie Hodge, gen eds., The New Answers Book 1 (Green Forest, AR: Master Books, 2020), 122-123.
[2] Batten, Catchpoole, Sarfati, Wieland, “What About Carbon Dating?” The Creation Answers Book (Australia: Creation Ministries International, 2012), 76-77; available at https://creation.com/images/pdfs/cabook/chapter4.pdf, accessed 9/27/21.
[3] See “Radiometric Dating Questions and Answers”, available at https://creation.com/radiometric-dating-questions-and-answers; accessed 9/27/21.
[4] Batten et. al; “What About Carbon Dating?” 76.
[5] Robert Carter, ed., Evolution’s Achilles’ Heels (Powder Springs, GA: Creation Ministries, Int’l, 2014), 197.
[6] Batten et. al; “What About Carbon Dating?” 78.
[7] Ibid.
[8] Ibid.
[9] Carter, ed., Evolution’s Achilles’ Heels, 208-209.
This is very good Greg…it obviously took a lot of study to find this out. THANKS!
I’m looking forward to the next post!
Elaine