WEBVTT - Age of the Earth, Part 2 0:00:03.000 --> 0:00:06.080 Welcome to Stuff to Blow your Mind from how Stuffworks 0:00:06.120 --> 0:00:14.160 dot com. Hey, are you welcome to step to Blow 0:00:14.160 --> 0:00:17.000 your Mind. My name is Robert Lamb and I'm Joe McCormick. 0:00:17.040 --> 0:00:20.000 And this is part two of our two part exploration 0:00:20.560 --> 0:00:22.720 of the Age of the Earth. If you have not 0:00:22.880 --> 0:00:25.680 heard part one of this episode, you should go back 0:00:25.720 --> 0:00:27.760 and listen to that first. That's really gonna lay the 0:00:27.760 --> 0:00:31.200 groundwork for everything we're talking about today. In the last episode, 0:00:31.240 --> 0:00:34.279 we talked about why we're addressing this topic even though 0:00:34.320 --> 0:00:38.600 it's a topic that there is not legitimate scientific controversy about. 0:00:38.840 --> 0:00:42.720 There's no real scientific argument about whether the Earth is 0:00:42.800 --> 0:00:46.159 billions of years old or younger. Uh, it is billions 0:00:46.159 --> 0:00:49.600 of years old. But we are addressing it because we've 0:00:49.680 --> 0:00:52.960 we've frequently gotten mail from listeners asking us to help 0:00:53.000 --> 0:00:56.600 them sort out and understand the differences in claims about 0:00:56.600 --> 0:01:00.000 the age of the Earth. So we're on that adventure now. Yeah, 0:01:00.040 --> 0:01:02.280 and if you listen to the first episode, I don't 0:01:02.520 --> 0:01:05.320 I do want to just tell everybody this one is 0:01:05.319 --> 0:01:07.880 is definitely worth listening to as well. It's not all 0:01:07.920 --> 0:01:10.759 gonna be elements and isotopes. There's gonna be some cool 0:01:10.800 --> 0:01:14.399 history in here. There's gonna be some some other dynamic 0:01:14.720 --> 0:01:17.520 geologic examples. So there's a there's a lot of cool 0:01:17.560 --> 0:01:20.600 stuff in this episode. Even if you don't need convincing 0:01:20.640 --> 0:01:23.080 about the scientific consensus about the age of the Earth, 0:01:23.360 --> 0:01:27.240 or you don't need uh ammunition for arguments with people 0:01:27.240 --> 0:01:29.760 who do hold onto a some sort of a h 0:01:30.040 --> 0:01:32.800 a young Earth view. Uh, there's gonna be a lot 0:01:32.840 --> 0:01:35.920 of fun in this episode regardless. Robert, I say, we 0:01:35.959 --> 0:01:39.360 should meet a scientist named Claire c. Patterson, who I 0:01:39.400 --> 0:01:42.440 will hereafter call the Lord of Lead. Lord of lad 0:01:42.480 --> 0:01:46.520 does sound a lot more metal, I will say, well, 0:01:46.560 --> 0:01:49.160 Claire Claire was a Lord of lad He. Claire Cameron 0:01:49.160 --> 0:01:53.040 Patterson lived nineteen twenty two to nineteen and he was 0:01:53.080 --> 0:01:55.960 a geochemist on the faculty at cal Tech and a 0:01:56.000 --> 0:01:58.880 member of the National Academy of Sciences. According to his 0:01:58.920 --> 0:02:01.520 New York Times A Bitch Worry by William Dick, he 0:02:01.560 --> 0:02:03.880 had something of a reputation as sort of a rebel 0:02:04.000 --> 0:02:07.960 and an outlier in his field, and Barclay cam who 0:02:08.040 --> 0:02:11.520 was provost at Caltech in the nineteen eighties, once said 0:02:11.560 --> 0:02:15.440 that Patterson's thinking and imagination were quote so far ahead 0:02:15.440 --> 0:02:18.480 of the times that he has often gone misunderstood and 0:02:18.560 --> 0:02:22.480 unappreciated for years until his colleagues finally caught up and 0:02:22.560 --> 0:02:25.720 realized he was right. Nothing to inflate your ego like 0:02:25.800 --> 0:02:31.040 somebody saying everybody will finally realize he's right. And speaking 0:02:31.040 --> 0:02:34.480 to an article in USA Today, the Caltech geologist John 0:02:34.520 --> 0:02:37.920 Eisler described him as fearless and said quote wherever the 0:02:37.960 --> 0:02:41.240 science took him, he would follow. And so Patterson was 0:02:41.320 --> 0:02:44.520 reportedly sometimes critical of colleagues who he might have referred 0:02:44.520 --> 0:02:48.600 to as ivory tower scientists. His research was definitely not 0:02:48.800 --> 0:02:53.520 confined to arcane academic matters. He got down into the world, 0:02:53.639 --> 0:02:56.600 into stuff that that had an impact on human life 0:02:57.160 --> 0:03:01.160 and for one thing, much of Patterson's important, most important 0:03:01.160 --> 0:03:05.240 work focused on measuring and contrasting levels of lead in 0:03:05.320 --> 0:03:09.480 the atmosphere at various times in history, and as the 0:03:09.560 --> 0:03:13.000 Lord of Lead, Patterson, using a variety of methods, demonstrated 0:03:13.040 --> 0:03:15.760 that people in the twentieth century were taking in these 0:03:15.960 --> 0:03:20.480 enormous doses of lead contamination in their bodies, uh much 0:03:20.520 --> 0:03:23.960 more than their prehistoric ancestors had consumed, and this exposure 0:03:23.960 --> 0:03:26.960 to lead has extreme consequences on the health of humans 0:03:26.960 --> 0:03:30.080 and other organisms. Lead gets in you. It effects everything 0:03:30.120 --> 0:03:33.320 from the brain to the kidneys. Um to quote from 0:03:33.320 --> 0:03:36.600 his New York Times obituary quote, he sampled snow from 0:03:36.600 --> 0:03:39.760 the ice caps of Greenland and Antarctica that had fallen 0:03:39.840 --> 0:03:42.720 hundreds or thousands of years earlier, showing there had been 0:03:42.760 --> 0:03:46.040 significant increases in lead in the northern Hemisphere when the 0:03:46.040 --> 0:03:50.320 Greeks and Romans smelted lead in antiquity. He discovered that 0:03:50.360 --> 0:03:52.840 millions of years ago, the amount of lead stored in 0:03:52.920 --> 0:03:56.960 microscopic plant and animal life or plankton in ocean sediments 0:03:57.040 --> 0:03:59.960 was only one tenth to one on the amount now 0:04:00.080 --> 0:04:04.440 flowing into the oceans from the continents. And so Patterson's 0:04:04.480 --> 0:04:07.000 research helped form the basis of the case for the 0:04:07.040 --> 0:04:10.120 Clean Air Act of nineteen seventy and the elimination of 0:04:10.200 --> 0:04:13.640 leaded gasoline, which was the biggest single cause of lead 0:04:13.680 --> 0:04:16.440 pollution in the environment at the time. All right, well, 0:04:16.480 --> 0:04:18.240 this is all, this is all well and good. I mean, 0:04:18.240 --> 0:04:21.080 this is great. Uh, but where does this where does 0:04:21.120 --> 0:04:24.240 he come into our discussion of the age of the Earth. Well, 0:04:24.480 --> 0:04:28.600 Patterson was also the first person to make an accurate 0:04:28.720 --> 0:04:31.040 estimate of the age of the Earth and the Solar System, 0:04:31.240 --> 0:04:34.719 which he published in the nineteen fifties based on the 0:04:34.760 --> 0:04:38.720 accumulating body of knowledge about radioactive decay. Now, if you 0:04:38.800 --> 0:04:41.800 remember in the previous episode, one of the types of 0:04:41.880 --> 0:04:47.080 radiometric dating we talked about was uranium lead dating, and 0:04:47.480 --> 0:04:50.880 so that studies the decay of a radioactive isotope of 0:04:51.000 --> 0:04:55.880 uranium into lead over millions of years, and so specifically, 0:04:55.920 --> 0:04:58.400 in Patterson's case, the key was to look at the 0:04:58.440 --> 0:05:01.400 Solar system at law to find out how old the 0:05:01.400 --> 0:05:04.680 Earth was. Since the evidence indicated that everything in the 0:05:04.680 --> 0:05:08.320 Solar System was formed around the same time, Patterson and 0:05:08.360 --> 0:05:11.400 others realized they could study the decay of uranium and 0:05:11.480 --> 0:05:16.560 thorium into daughter isotopes of lead in meteorites to determine 0:05:16.560 --> 0:05:19.960 the age of the Solar System objects, including the Earth, 0:05:20.160 --> 0:05:22.160 and so in the nineteen fifties, I think the late 0:05:22.160 --> 0:05:25.560 forties and early late forties and the fifties, Patterson used 0:05:25.600 --> 0:05:29.640 mass spectrometry to study Earth based zircons. Those are these 0:05:29.640 --> 0:05:32.640 little crystals I talked about in the previous episode that 0:05:32.760 --> 0:05:36.840 are usually formed with zirconium atoms in them, but sometimes 0:05:36.880 --> 0:05:40.880 get radioactive uranium atoms lodged into them, and these the 0:05:40.960 --> 0:05:46.040 decay of these radioactive uranium atoms inside the zircon crystals 0:05:46.320 --> 0:05:49.560 can be used to date the crystals. So he was 0:05:49.560 --> 0:05:53.279 studying Earth based zircons and uranium lead decay and meteorite 0:05:53.320 --> 0:05:57.160 material and ultimately Patterson was able to pin the date 0:05:57.240 --> 0:06:00.400 of the solar systems accretion including the Earth to about 0:06:00.480 --> 0:06:04.039 four point five billion years, which is still basically the 0:06:04.120 --> 0:06:07.159 accurate figure. And I love this link between his work 0:06:07.240 --> 0:06:11.520 on like environmental contaminants and and lead in human life, 0:06:12.040 --> 0:06:15.160 uh to to studying the very origin of the Earth. 0:06:15.240 --> 0:06:17.640 That's that's some of the best stuff in science. When 0:06:18.080 --> 0:06:20.960 when knowledge gets applied in such different ways like that, 0:06:21.120 --> 0:06:23.560 it really gets my gears going right at the human 0:06:23.640 --> 0:06:27.600 level and right at the essentially the god level. So 0:06:27.640 --> 0:06:30.359 earlier I mentioned the quote from John Eiler talking to 0:06:30.440 --> 0:06:33.560 USA Today, UH and Eiler makes this case pretty well. 0:06:33.600 --> 0:06:36.240 He says, quote Patterson is a pretty clear example of 0:06:36.279 --> 0:06:40.360 the link between basic science that seems unrelated to everyday life, 0:06:40.680 --> 0:06:42.960 the age of the Earth, and science that makes a 0:06:43.000 --> 0:06:46.839 crucial difference every moment in our everyday lives. There really 0:06:46.920 --> 0:06:49.640 isn't a difference between the skills the methods and the 0:06:49.720 --> 0:06:52.880 thinking that led him to both discoveries. And that's the 0:06:52.920 --> 0:06:56.000 story of science. And I love that quote because I 0:06:56.000 --> 0:06:57.800 feel like that's sort of the case we're trying to 0:06:57.839 --> 0:06:59.800 make in these episodes, right that there's sort of a 0:06:59.800 --> 0:07:04.440 coherent scientific approach to looking at the world around you. 0:07:04.880 --> 0:07:08.080 And in order to reject the age of the Earth 0:07:08.120 --> 0:07:10.239 and say that the Earth is just a few thousand 0:07:10.280 --> 0:07:14.200 years old, you're not just arguing with a particular method 0:07:14.200 --> 0:07:17.080 of radiometric dating, as we will continue to explore throughout 0:07:17.080 --> 0:07:19.920 the rest of this episode, it's essentially a rebuke of 0:07:19.920 --> 0:07:23.240 the entire scientific way of looking at the world. Yeah, 0:07:23.320 --> 0:07:26.240 it would really force you to throw the trigonometry baby 0:07:26.280 --> 0:07:32.120 into the ocean, and and you shouldn't have to do that. Um. So, 0:07:32.640 --> 0:07:35.160 there are a lot of difficulties Patterson had in his work, 0:07:35.240 --> 0:07:39.360 so he had to develop extremely stringent experimental procedures in 0:07:39.440 --> 0:07:42.800 order to get accurate results. That the Time's obituary talks 0:07:42.840 --> 0:07:45.240 about this. I've read about this elsewhere too, that he 0:07:45.400 --> 0:07:49.600 found that lead contamination was just everywhere. So scientific labs 0:07:49.600 --> 0:07:52.840 are full of lead contaminants because of all all kinds 0:07:52.840 --> 0:07:55.960 of lead pollution. And if you're trying to measure minute 0:07:56.080 --> 0:07:59.320 ratios of lead isotopes inside a hunk of meteorite. You 0:07:59.320 --> 0:08:02.280 don't want to be taminating it with lead from I 0:08:02.320 --> 0:08:04.600 don't know, the car exhaust he walk through on the 0:08:04.600 --> 0:08:07.800 way to the lab, and all other kinds of ambient 0:08:07.880 --> 0:08:11.080 lead that are currently poisoning your body. So he established 0:08:11.080 --> 0:08:14.680 clean room procedures, including like washing your hands and distilled 0:08:14.760 --> 0:08:17.240 water and putting on all the you know, all the 0:08:17.560 --> 0:08:19.560 what are the when people go and work on the 0:08:19.640 --> 0:08:22.760 chips in the laboratories, Those suits and all of this 0:08:22.800 --> 0:08:25.760 should help us notice that radiometric dating has all kinds 0:08:25.800 --> 0:08:29.760 of important caveats, Like pretty much all types of chemical measurement. 0:08:30.120 --> 0:08:34.320 It can be subject to sample contamination, to equipment malfunction, 0:08:34.480 --> 0:08:37.280 to user error, and so forth. And this is why 0:08:37.320 --> 0:08:42.000 it's really important to corroborate any radiometrically generated date with 0:08:42.160 --> 0:08:46.920 multiple tests and if possible, with multiple methods. Also, when possible, 0:08:46.960 --> 0:08:50.720 I think it's better to think about radiometric dating instead 0:08:50.760 --> 0:08:53.760 of giving us a date, giving us sort of confidence 0:08:53.880 --> 0:08:57.480 ratings for different ranges of dates. So, just as an example, 0:08:58.480 --> 0:09:01.520 a radiometric test or series of tests might tell us 0:09:01.600 --> 0:09:05.840 that we're sure that the thing is between four and 0:09:05.920 --> 0:09:09.400 five billion years old, and seventy percent sure that it's 0:09:09.400 --> 0:09:12.120 between four point five and five points or four point 0:09:12.200 --> 0:09:15.040 six billion years old, and that kind of thing, right, Yeah, 0:09:15.040 --> 0:09:17.079 I mean there is there is a certain amount of 0:09:17.120 --> 0:09:21.160 uncertainty baked into the process, right, But it will tell 0:09:21.200 --> 0:09:25.400 you bigger ranges with greater certainty. But what about rocks 0:09:25.440 --> 0:09:28.400 from the Earth itself? This can be more difficult since 0:09:28.440 --> 0:09:31.280 the Earth is just frequently eating and barfing up its 0:09:31.280 --> 0:09:34.079 own crust. It's part of how Earth is. Yeah, it's 0:09:34.160 --> 0:09:37.360 it's it's dynamic. Yeah uh, and this this can be 0:09:37.400 --> 0:09:40.760 more difficult. So rocks from billions of years ago often 0:09:40.800 --> 0:09:43.240 tend to disappear into the bowels of the Earth. They 0:09:43.240 --> 0:09:45.160 get gobbled up in one way or another, they get 0:09:45.240 --> 0:09:49.120 subducted or something like that. But sometimes we can find them. 0:09:49.160 --> 0:09:52.280 And it's pretty common to read about discoveries of increasingly 0:09:52.440 --> 0:09:55.360 ancient rocks found on Earth. Just I was looking at 0:09:55.400 --> 0:09:58.040 a few articles from recent years. One is that um 0:09:58.320 --> 0:10:02.400 rocks from the Acosta Knife in the Northwest territories of Canada. 0:10:02.440 --> 0:10:04.960 And that's nice g N E I S S. That's 0:10:04.960 --> 0:10:08.880 a geological term, not not like, oh, nice um that 0:10:09.080 --> 0:10:11.800 those have been dated to more than four billion years old. 0:10:12.960 --> 0:10:15.680 In September two thousand eight, there was a National Science 0:10:15.720 --> 0:10:18.360 Foundation press release. I was reading about a piece of 0:10:18.360 --> 0:10:21.880 Canadian bedrock from the and I'm sorry if I mispronounced this, 0:10:22.000 --> 0:10:26.360 the Neuvo Agatuck Greenstone Belt, which was dated to between 0:10:26.400 --> 0:10:29.400 three point eight and four point to eight billion years old. 0:10:29.800 --> 0:10:33.120 And then also there is a zircon from the jack 0:10:33.200 --> 0:10:36.280 Hills of Western Australia that's been dated to over four 0:10:36.320 --> 0:10:39.959 billion years I think about four point four billion years old. 0:10:40.360 --> 0:10:42.600 So here and there we find little bits of the 0:10:42.640 --> 0:10:45.160 surface of the Earth that seemed to go almost all 0:10:45.200 --> 0:10:47.880 the way back to the beginning and certainly back before 0:10:47.960 --> 0:10:50.840 say that's six thousand year point. Yeah, I mean they're 0:10:50.880 --> 0:10:54.440 they're not just quibbling with the six thousand year point. 0:10:54.480 --> 0:10:58.040 They're saying it is so many orders of magnitude off. 0:10:58.880 --> 0:11:01.320 As we said that, they just of confidence intervals. They 0:11:01.320 --> 0:11:03.840 don't tell you an exact date. So you know, you 0:11:03.880 --> 0:11:07.400 could quibble here or there with calibrating the correct date 0:11:07.440 --> 0:11:10.040 of these rocks, but they're not going to calibrate orders 0:11:10.080 --> 0:11:12.559 of magnitude down. It just comes back to what I 0:11:12.760 --> 0:11:15.880 said in the last episode about the difference between the 0:11:15.880 --> 0:11:18.719 scale of human history and the scale of geologic history, 0:11:19.120 --> 0:11:23.360 religion and myth with with a with some notable exceptions 0:11:23.880 --> 0:11:27.000 tend to take place within human history because it is 0:11:27.040 --> 0:11:29.800 a product of human understanding. That's a good point. Our 0:11:29.840 --> 0:11:34.840 our minds are just not made to contemplate time scales 0:11:34.960 --> 0:11:38.480 like this. It's not I would argue, actually, it's not 0:11:38.720 --> 0:11:43.240 just theological beliefs that drive people to want to imagine 0:11:43.600 --> 0:11:45.760 a younger Earth. I think. I mean, it's also like, 0:11:45.960 --> 0:11:48.640 if you want to wrap your brain around the history 0:11:48.679 --> 0:11:50.520 of the Earth, you're not going to be able to 0:11:50.600 --> 0:11:53.080 do it with a four point five billion year old Earth. 0:11:53.160 --> 0:11:56.040 You're not really picturing that time. You're just sort of 0:11:56.080 --> 0:12:00.240 condensing it into a representation of a timeline you can 0:12:00.360 --> 0:12:03.200 kind of picture, right, I mean they I mean, how 0:12:03.200 --> 0:12:06.959 do you put that into a perspective of generations? Right, 0:12:07.440 --> 0:12:10.079 and and and so and so begot so and so, 0:12:10.200 --> 0:12:11.959 you know, I mean it doesn't work right, I mean, 0:12:12.000 --> 0:12:14.480 And I mean and I'm not just you know, harping 0:12:14.520 --> 0:12:17.800 on you know, books of the Bible or anything here, 0:12:17.880 --> 0:12:21.640 but just the human perspective, the human shape of things, 0:12:21.679 --> 0:12:24.880 Like we just have a tendency to understand those better, 0:12:24.920 --> 0:12:28.320 to understand those stories better. Again, the the appeal of 0:12:28.360 --> 0:12:33.000 storytelling versus the kind of data that is involved in 0:12:33.000 --> 0:12:37.800 in rigorous scientific understanding. Yeah, and I mean we are 0:12:37.840 --> 0:12:41.719 always vulnerable to this. Stories are more compelling. Stories are 0:12:41.720 --> 0:12:43.960 more compelling than data. They shouldn't be. I mean, the 0:12:44.040 --> 0:12:47.040 data are actually more reliable. But what are people going 0:12:47.080 --> 0:12:50.199 to remember better a story? What's going to connect better 0:12:50.240 --> 0:12:53.960 with people emotionally is a story. Even even people who 0:12:54.000 --> 0:12:57.560 try to be scientifically minded are highly vulnerable to stories. 0:12:57.600 --> 0:13:03.080 I think about the most if effective science communication books 0:13:03.520 --> 0:13:07.320 try to be story based. Like in in our last episode, 0:13:07.440 --> 0:13:08.800 you know, there was a point where we had to 0:13:08.840 --> 0:13:11.960 talk about radioisotopes and stuff like that in order to 0:13:12.000 --> 0:13:16.560 explain how how radioactive decay works. But talking about how 0:13:16.760 --> 0:13:20.360 radioisotopes decay is not as compelling as like telling the 0:13:20.400 --> 0:13:23.720 story of the Lord of Lead anyway, I mean to 0:13:23.760 --> 0:13:26.440 derail the conversation. I can I can talk all day 0:13:26.440 --> 0:13:29.480 about you know, science and religion and where and where 0:13:29.520 --> 0:13:32.200 and when they can line up and and um and 0:13:32.200 --> 0:13:34.760 and support each other. Really, you mean like we need 0:13:34.800 --> 0:13:38.200 to create new religious narratives that that that help people 0:13:38.240 --> 0:13:41.000 confirm scientific knowledge, or I mean part of it is 0:13:41.000 --> 0:13:43.280 realizing what kind of answers religion can provide versus what 0:13:43.360 --> 0:13:46.360 kind of answers uh science can provide. Um. It's been 0:13:46.400 --> 0:13:50.480 pointed out, for instance, that uh, you can take the 0:13:50.559 --> 0:13:54.320 question why and they're they're essentially two different versions of why. 0:13:54.440 --> 0:13:57.480 There's a causal why, and there's a teleological why. There's 0:13:57.520 --> 0:14:01.320 the why like why is this, Why did this happen? 0:14:01.400 --> 0:14:05.200 What is the thing uh that preceded it? What was 0:14:05.240 --> 0:14:08.360 the process physical chain of events that caused it? Right? 0:14:08.400 --> 0:14:10.559 And then on the other hand that the telological why 0:14:11.000 --> 0:14:15.240 is for what reason is this as it is? For 0:14:15.320 --> 0:14:19.120 what reason? Am I? What I am? And so um 0:14:19.240 --> 0:14:22.320 I mean, broadly speaking, you can say that religion can 0:14:22.360 --> 0:14:28.240 provide the teleological and science provides the causal Um. Religion 0:14:28.320 --> 0:14:31.720 is very good at providing a sense of narrative, as 0:14:31.760 --> 0:14:33.640 we were just talking about narratives and stories, a sense 0:14:33.680 --> 0:14:37.920 of narrative or story that that makes sense of things. 0:14:38.440 --> 0:14:40.760 But again, I don't mean to derail the conversation. I 0:14:40.800 --> 0:14:42.720 could talk about that all day. Well, yeah, but I 0:14:42.720 --> 0:14:44.120 guess I guess we've got to get back to the 0:14:44.160 --> 0:14:46.040 idea of what we're setting out to talk about we 0:14:46.040 --> 0:14:49.240 have a lot of impersonal geology to unpack here. No, 0:14:49.400 --> 0:14:51.880 we'll try to make it as personal it's and it's 0:14:51.920 --> 0:14:54.840 exciting stuff. It is dynamic. We're talking about the stuff 0:14:54.880 --> 0:14:58.440 of of you know, earthquakes and volcanoes here. So so 0:14:58.760 --> 0:15:01.040 you might be thinking, you you've heard us talk about 0:15:01.120 --> 0:15:05.400 radio isotope decay, about radiometric dating, about Claire Patterson, and 0:15:05.440 --> 0:15:08.920 you think, yeah, but how do we know these methods 0:15:08.920 --> 0:15:11.360 of dating the Earth actually work? Like are we just 0:15:11.480 --> 0:15:14.200 taking some scientist's word for it? Like what if a 0:15:14.240 --> 0:15:18.200 scientist is lying and saying it works but it doesn't. Really, 0:15:18.760 --> 0:15:23.600 that's not really a plausible critique because like the yes, 0:15:23.680 --> 0:15:28.240 but what if it wasn't response? I can explain why 0:15:28.240 --> 0:15:31.240 it's not a plausible critique. And one strong line of 0:15:31.280 --> 0:15:36.400 evidence is when multiple independent tests with different methods produce 0:15:36.560 --> 0:15:39.240 results that are in agreement with each other. The simple 0:15:39.360 --> 0:15:41.840 version of this is, um, how do you know when 0:15:41.920 --> 0:15:45.360 eyewitness testimony is good? Right? You know? And eyewitness can 0:15:45.400 --> 0:15:47.520 get all kinds of stuff wrong. We explore that on 0:15:47.560 --> 0:15:50.240 the podcast all the time. So say you you know, 0:15:50.560 --> 0:15:52.400 you arrive at the scene of a crime, you pull 0:15:52.480 --> 0:15:56.160 up at the video store, and uh, and somebody has 0:15:56.200 --> 0:15:59.000 just sped away stealing a priceless copy of Highlander. To 0:15:59.080 --> 0:16:03.120 the quickening, I mean, especially if you're an orthodox Highlander 0:16:03.160 --> 0:16:08.600 tooth than as except no director's cut, except no renegade 0:16:08.600 --> 0:16:12.040 cut unacceptable. You've got to get the original version on 0:16:12.200 --> 0:16:15.200 VHS that's got all the bad scenes. It's the only 0:16:15.200 --> 0:16:18.040 way to feel the quickening. But yeah, so you get 0:16:18.040 --> 0:16:20.720 on the scene a copy of Highlander two has been stolen, 0:16:20.720 --> 0:16:22.840 and you want to find out who did it. Fortunately, 0:16:22.840 --> 0:16:25.840 there are several people standing around it just happened. So 0:16:26.040 --> 0:16:29.320 you separate all the people and they can't talk to 0:16:29.360 --> 0:16:31.280 each other, and you interview them one at a time, 0:16:31.320 --> 0:16:33.520 And the first witness tells you that it was a 0:16:33.600 --> 0:16:36.360 man wearing a kilt with a bagpipe on his back 0:16:36.720 --> 0:16:39.120 and a katana sword hanging from his hip, and he 0:16:39.200 --> 0:16:41.240 ran into the store and he yelled, there can be 0:16:41.320 --> 0:16:44.840 only one and he grabbed the tape and he ran out. Now, 0:16:45.200 --> 0:16:48.280 as we've said, I witness testimony can be very faulty 0:16:48.320 --> 0:16:50.880 sometimes people they are all kinds of issues with perception 0:16:50.960 --> 0:16:53.680 and memory. But if you talk to the second witness 0:16:53.760 --> 0:16:57.480 and they independently mentioned all the same stuff. They kill, 0:16:57.680 --> 0:17:00.920 the bagpipe, the katana, and you talk to a third 0:17:01.000 --> 0:17:03.800 witness they mentioned all the same stuff again, you really 0:17:03.840 --> 0:17:06.400 have to think, Okay, if they haven't talked to each 0:17:06.440 --> 0:17:09.199 other and they're all telling me all the same details, 0:17:09.440 --> 0:17:12.120 what are the odds that three people are getting all 0:17:12.160 --> 0:17:15.480 this different stuff wrong in the same way. And that's 0:17:15.480 --> 0:17:18.080 how corroboration of dating methods works. It's like having a 0:17:18.160 --> 0:17:21.240 second witness or a third witness on the scene who 0:17:21.280 --> 0:17:24.159 independently tells you they saw the same thing that the 0:17:24.160 --> 0:17:27.199 other witnesses did. It's possible they could be all they 0:17:27.240 --> 0:17:28.840 could all be wrong, But if they haven't talked to 0:17:28.880 --> 0:17:31.400 each other, why would they all be wrong the same way? 0:17:31.880 --> 0:17:33.480 All right, Well, on that note, let's take a quick 0:17:33.480 --> 0:17:35.600 break and we come back. We'll jump right back into 0:17:35.600 --> 0:17:41.000 the discussion. Thank alright, we're back, alright. So I wanted 0:17:41.040 --> 0:17:44.200 to talk about a really great article that I read 0:17:44.200 --> 0:17:48.320 on this subject about how to corroborate the dating methods 0:17:48.440 --> 0:17:51.520 that are used in h in radiometric dating and establishing 0:17:51.560 --> 0:17:53.600 the Age of the Earth, and the articles by the 0:17:53.640 --> 0:17:57.439 American geologist Brent Dalrymple, who worked for the U S 0:17:57.480 --> 0:18:00.720 Geological Survey and was a professor at Oregon State University, 0:18:00.800 --> 0:18:02.919 and he published a book on the Age of the 0:18:02.960 --> 0:18:05.920 Earth called The Age of the Earth with Stanford University 0:18:05.960 --> 0:18:09.879 Press in And so he's got this really excellent article 0:18:09.960 --> 0:18:12.720 hosted on the National Center for Science Education website and 0:18:12.760 --> 0:18:16.480 which he picks out four different examples, basically four studies 0:18:16.520 --> 0:18:20.400 that he had personal experience with in which radiometric date 0:18:20.520 --> 0:18:24.760 ranges were corroborated by multiple kinds of tests, multiple labs 0:18:24.840 --> 0:18:28.000 that showed them to be accurate. Um, So it's again 0:18:28.080 --> 0:18:30.320 not just that we do one test and assume it's 0:18:30.400 --> 0:18:33.720 the answer is right, but we test multiple samples, multiple methods, 0:18:33.760 --> 0:18:38.040 multiple labs and get agreement on the results. So, first example, 0:18:38.040 --> 0:18:41.560 he gives the Manson meteorite impact site and the Pierre 0:18:41.600 --> 0:18:45.399 Shale the Manson the Manson meteorite. There's got to be 0:18:45.440 --> 0:18:47.800 a metal band for this one. And also this has 0:18:47.840 --> 0:18:50.280 nothing to do with Charlie though right as I don't know, 0:18:50.680 --> 0:18:53.919 uh it's Manson Iowa. Does Manson Iowa have anything to 0:18:53.920 --> 0:18:57.720 do with Charlie does? But it's still hard to shake 0:18:57.800 --> 0:19:01.000 that possible connection. Okay, well, this is a look at 0:19:01.119 --> 0:19:04.080 argon argon dating, argne orgon dating is a method that's 0:19:04.080 --> 0:19:07.600 a derivative of the classic potassium argone dating method, but 0:19:07.640 --> 0:19:11.240 it's now considered a more accurate version of that decay 0:19:11.280 --> 0:19:14.920 series test. It helps detect errors protect against an accurate results. 0:19:15.520 --> 0:19:18.560 And so during the Cretaceous period, we know that there 0:19:18.640 --> 0:19:21.040 was a big old meteorite the hit part of what 0:19:21.200 --> 0:19:24.120 is now Iowa in the United States, near Manson, Iowa 0:19:24.680 --> 0:19:28.080 and uh. The hot impact melted a bunch of feldspar 0:19:28.200 --> 0:19:30.840 crystals and the granite rockley are near the surface of 0:19:30.920 --> 0:19:34.400 the time, and when these crystals are melted, their internal 0:19:34.520 --> 0:19:38.200 radiometric clocks get reset to zero. So if you use 0:19:38.359 --> 0:19:41.480 argon argon dating to date these melted crystals, you'll get 0:19:41.480 --> 0:19:45.280 an age of about seventy four point one million years. However, 0:19:45.520 --> 0:19:48.720 when the Manson media write hit, it also created what's 0:19:48.760 --> 0:19:52.360 known as shocked quartz crystals that exploded up into the air. 0:19:52.840 --> 0:19:55.320 They came down west of the impact and what's what 0:19:55.400 --> 0:19:57.720 was then an inland see and now you can find 0:19:57.760 --> 0:20:00.080 the shocked quarts from this impact in a thing in 0:20:00.200 --> 0:20:03.920 layer that's known as the Crow Creek member, and that's 0:20:03.960 --> 0:20:08.320 been within this larger sedimentary rock formation called the Pierre Shale. 0:20:08.880 --> 0:20:12.879 The Pierre Shale also contains marine fossils like ammonites and 0:20:13.040 --> 0:20:17.959 ash from volcanic eruptions. These ash beds from the volcanic eruptions, 0:20:17.960 --> 0:20:20.840 they've also got minerals in them like sanity and feldspar 0:20:20.960 --> 0:20:24.600 and biotite which have been independently dated using the argon 0:20:24.760 --> 0:20:28.920 argon method. And so there there's a study that that 0:20:29.080 --> 0:20:35.040 the Dalrymple sites from Isaac Koban Dalrymple and Obradovich in 0:20:35.440 --> 0:20:40.400 n in the Geological Society of America bulletin. And what 0:20:40.440 --> 0:20:42.920 did they find. So they found more than a half 0:20:43.000 --> 0:20:46.600 dozen dates of biotite and sanitine surrounding the Crow Creek 0:20:46.680 --> 0:20:49.760 member where the where the evidence of this impact near 0:20:49.760 --> 0:20:53.800 Manson was and interesting, so remember that the melted feldspar 0:20:53.920 --> 0:20:56.360 crystals from the impact were dated to seventy four point 0:20:56.440 --> 0:21:00.119 one million years old. The minerals found right below the 0:21:00.160 --> 0:21:02.560 impact layer, so that means they should be a little 0:21:02.560 --> 0:21:04.840 bit older, came up with dates about seventy four to 0:21:04.920 --> 0:21:08.240 seventy five million years old. The minerals found right above 0:21:08.320 --> 0:21:10.679 the impact layer, which should be a little bit younger, 0:21:10.960 --> 0:21:14.040 got results indicating they were about seventy three to seventy 0:21:14.040 --> 0:21:17.640 four million years old. So these dates for each mineral 0:21:17.720 --> 0:21:20.880 we're all corroborated with multiple sample tests to make sure 0:21:20.920 --> 0:21:24.200 they all agreed, and they tested with different kinds of minerals, 0:21:24.200 --> 0:21:27.760 and the results agreed. The biggest discrepancy and results came 0:21:27.800 --> 0:21:30.480 from comparing the biotite and the sanity and from the 0:21:30.560 --> 0:21:33.520 layer right below the impact, but this was less than 0:21:33.560 --> 0:21:37.240 a one percent difference. Also, the dates generated by the 0:21:37.359 --> 0:21:40.520 argon argne tests generally agree with how old these layers 0:21:40.560 --> 0:21:42.640 of rock are supposed to be and with the kinds 0:21:42.680 --> 0:21:45.359 of fossils we'd expect to find in them. So if 0:21:45.400 --> 0:21:48.080 the dating method is not reliable, why do so many 0:21:48.160 --> 0:21:51.840 different tests of different minerals from different time periods agree 0:21:51.920 --> 0:21:55.240 with each other and fit together in the correct plausible 0:21:55.320 --> 0:21:58.040 geological order. And this is another thing we haven't even 0:21:58.080 --> 0:22:03.240 talked about much yet, is the the idea of geologic stratification, 0:22:03.480 --> 0:22:07.760 like that there are layers of deposition of sedimentary that 0:22:07.880 --> 0:22:11.680 happened over time and volcanic deposits from volcanic eruptions that 0:22:11.800 --> 0:22:14.040 you can see going back through time. And you know, 0:22:14.560 --> 0:22:17.920 there were paleontologists who were looking at fossil layers in 0:22:18.080 --> 0:22:23.399 rock formations going down this uh stratigraphic column looking at 0:22:23.480 --> 0:22:26.760