How Accurate Is Radiometric Dating? - SC2529

SPEAKER 1 Welcome to Science Conversations. I'm Kaysie Vokurka. How accurate is radiometric dating? Joining me to discuss part two of this topic is Dr. John Ashton. Welcome to the program, Dr. John. SPEAKER 2 Hello, Kaysie. SPEAKER 1 Dr. John Ashton has written a book entitled Evolution Impossible 12 Reasons why Evolution Cannot Explain the Origin of Life on Earth. And we'll be referring to chapter 10 of his book in this program. So, John, there are many different radioactive isotopes that can be used to test and date rocks. If people use a number of different isotope testing for the same sample, what kind of results can we see? SPEAKER 2 Right, okay. Well, this is quite an interesting area when we look at dating rocks. Of course, as you say, depending on the minerals, there are a number of different methods that we can use. And it's quite fascinating what the results are. But I think one of the important areas to look at is that initially, when we compare the dates of conventional dating from the fossil record, for example, the traditional dates that have been applied, and then we date by standard methods, we get quite different results. So we get different results, often get quite different results. Now, it's interesting. Back when I was teaching physics in the mid-80s, one of the textbooks on the principles of isotope geology that came out then was by G. Furey, and he was one of the authorities in radiometric dating in the world at that time. And he actually points out a number of cases where radiometric dating data and dating is just wrong. And again, it's one of these areas that people have to be aware of. So it's a number of cases. For example, he cited studies that were done on some lava that was dated less than 1.6 million years according to its position in the rock layer. And yet using the rubidium strontium dating, it was dated at 773 million years. So there's no. No. SPEAKER 1 Or is it more. SPEAKER 2 1.6 million. SPEAKER 1 Oh, million. SPEAKER 2 One and a half million. And then it was stated at 773 million. So that's. SPEAKER 1 That's a lot more. SPEAKER 2 Yeah. Wow. That's 700 times more. SPEAKER 1 That's huge. SPEAKER 2 It gives another example of upper Miocene to Pliocene larva, which was traditionally dated 5 to 9 million years old and by potassium argon and dated at 31 to 39 million years old using rubidium strontium. So we can see there that this is what you were talking about earlier when we use potassium argon, 5 to 9 million years using the rubidium strontium, 31 to 39 million years. So again, a huge difference there. Which date do you take? Well, the date that they take, if it fits closest, closest one, they pick the one that's closest to the actual fossil record. So you can see there's a basis, a bias here. Yes, we can get a whole lot of different results. We're saying, oh, the other ones must be wrong. We don't know why they're wrong. But hang on, we'll choose this one because this is closest to the one we expect to get. Yeah, a number of classic examples of this. Another case of some larva that strategically was dated at Pliocene to Holocene. So that's, you know, current that is less than 5.3 million years old. And it gave rubidium strontium ages of 570 million years. So this is should be only 5 million, but 570 million years with rubidium strontium. And another method gave 870 million years, another rock in the same age. So it should be fairly young, about five. Less than five million. Five million years old. Gave was dated as one and a half thousand million years old by rubidium strontium. So these, you know, we could go through a whole lot of another rock that was assigned as less than 24 million years old according to the fossil record, but dated as 1200 million years old by rubidium strontium method. Now these are what, these examples that I've just read out are all from the textbook, right. Warning Students, that was published by Wiley and sons back in 1986. And so, you know, we need to understand this. And again, if we look, say at some more recent data, for example, here in Australia, the Somerset Dam up in Queensland there, there's a Jurassic Triassic intrusion that's supposed to be around about 220 million years old there. This is from the fossil record. And it gave potassium argon ages range from 183 to 252. With the isochron dates, that's the accurate method of 174 million years. So it's supposed to be 220. The accurate method gave 174 million years and the error was only plus or minus 9. When they dated with the rubidium strontium isochron method, they got an age of 390 million years. When they dated the using the samarium neodymium isochrome method, an age of 259 million years. But it's interesting, the lead lead method gave an age of about 1400 million years, plus or minus 1000 million years. So again, so how old was the intrusion? 174 million years or 1425 million years. These are the range of ages for the same intrusion. This 1997 results. SPEAKER 1 Wow. And so this is, we've got the same sample, we are applying different radiometric methods on the same sample and we're getting a vast majority. SPEAKER 2 We're getting this huge. So if you're doing your master's thesis or your PhD or Honours thesis, I was studying these rocks. The result that you would pick is the one that's closest to the fossil dating method. And how is the fossil dating method worked out? It was worked out by assuming uniform deposition of sediment over hundreds of millions of years that contradicts erosion rates and plus the evidence for catastrophic path. So you can see we've got major problems. And yet these dates are slam, you know, are put up on big billboards at national parks and all this sort of thing and people, and they're so, you know, widespread, so ubiquitous, so to speak, that people have just assumed, oh, these ages are all correct. Yeah. SPEAKER 1 What is so, I guess puzzling to me is in any other field of science or a scientific study, if you had data across the spectrum and then you picked and choose the data according to what fit a theory which you aligned to that would be looked down upon very much as you skewed the data. You're cherry picked it. Yeah. And now you're presenting information that's misleading the public if it, if it's related to a public issue and that that's like a big no, no for true science. And yet in here it's done and it's, it's just left and it's considered normal. It's a con, It's a huge contrast to me. SPEAKER 2 Yes. Yeah. Well, of course public doesn't know about this. And this is the sad part. And the people in museums, people working in other fields, they don't realize this is happening. You know, I, one of the scientists I know that worked in this area, PhD from the University of Sydney in geology, did radiometric dating of uranium deposits as part of his doctorate and work afterwards. And he found a rock, a piece of lava that had encased some wood. When they dated the wood, they got about 30,000 years. When they dated the rock, they got about 30 million years. SPEAKER 1 Oh, wow. SPEAKER 2 So you got a, you know, so how old is it? How old? You know, the wood's saying, hang on, it's only 30,000. The Rock's saying, Hang on, it's 30 million. Yeah. These are rough figures. It might have been 37 million, you know. Well, yeah, but there was this huge, huge, huge contrast Here. And this has happened too, when they've measured rocks at the base of the Grand Canyon. And this sort of thing, depending on the method that they get, and they get huge ranges, you know, they might get a range of 600 million years difference between the different methods. And so what do they do? They settle on a method that's closest to the states. SPEAKER 1 So another question for you. What about for rocks where they already know how old the rock is based on history or something? So they know there was like the volcanic eruption 300 years ago. That means this rock is this age. Let's now test it and see if the dating lines up. How does that kind of. How does that show? SPEAKER 2 Well, that's a good question. And that's been done. For example, we have historical lava flows in Hawaii and that were about 200 years old, something like that, and they were dated as 3.34 billion years old. SPEAKER 1 For rock that's only 200 years old. SPEAKER 2 Yep. And the same dating lava from Vesuvius and all these sort of known volcanoes, when the lava flows, historical ranges from 100 million years old to 10,000 million years old, like 10.5 billion years old, which is older than the age of the Earth because it's only supposed to be four and a half billion years old. SPEAKER 1 That's a bit of a problem, isn't it? SPEAKER 2 And if any of the listeners are interested in that. Yeah, that was some work that was published. Well, that work was done back in 1970. It's interesting, some work that was done at the Australian National University School of Earth Sciences samples from the Mount Noahoe eruption in New Zealand in the early 1950s, I think 954. So those rocks were dated in 1999 or around 2000, something like that. So they're a bit less than 50 years old. And those results are very, very interesting. So they were analyzed by the PR I S E Laboratory and the Research School of Earth Sciences at the Australian National University. The rubidium strontium isotope gave an age of 133 million years, postmised 87 million years. The samarium neodymium isochron gave an apparent age of 197 million years. Posthumous 160 million years. And the lead, lead isochron gave an apparent age of 3.908 plus or minus 390 million years. So nearly 4000 million years from lead, around 200 million years for samarium neodymium and 130 million years for rubidium strontium on rocks that were less than 50 years old. And similar data has been done on the lava from the Mount St. Helens eruption. And again, they've got ages, hundreds of thousands of years for rocks that were about 20 years old when the work was done. So we can see here, it's crazy. And that would be the way of validating the method because you have a rock of known age, of course it would be. And you measure its age and we get these, these huge ages for rocks that we actually know are young. And this is crucial evidence that we have major problems with the radiometric dating method. And again, you know, we've got, probably one of the best universities in Australia did this work to analyze these, these rocks here. And it's consistent. When they do analyze known historical date rocks that are only hundreds of years old or 1,000 years old, whatever, we get millions of years for the ages. And so again, this should ring alarm bells when we're posting all these millions of years, ages around, flaunting them all around. They're very inconsistent with what we've. If we have a rock of known ages and analyze them, we get those ridiculous ages. This should be really throwing up red lights. We've got major, major problems with this method. SPEAKER 1 Absolutely. Time to completely reevaluate. That's what it's saying to me, that kind of evidence. Yeah, absolutely fascinating and important stuff. We're going to keep talking about this in the next session as we examine the question, how accurate is radiometric dating? Be sure to join us.