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How to date an archaeologist: Radiocarbon dating - Ep 27
290 Plays4 months ago
It’s time for the first episode of our Tea-break Time Travel training series, where we cover all of those essential theoretical and methodological backgrounds that every time traveller needs to have under their belt. This month, we’re kicking things off with one of the most popular archaeological dating methods: radiocarbon dating. But what exactly is radiocarbon dating? How do you do it? And why does it matter if people in the past left a lot of fish-bones behind? Tune in to find out!
Transcripts
- For rough transcripts of this episode go to https://www.archpodnet.com/teabreak/27
Links
- Nobel prize lecture from William Libby
- Detailed paper on the marine reservoir effect
- Case study demonstrating marine reservoir effect
- Detailed article on the history of radiocarbon dating
- Paper on radiocarbon dating
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Transcript
Introduction & Tea Discovery
00:00:00
Speaker
You're listening to the Archaeology Podcast Network. um You're listening to Tea Break Time Travel, where every month we look at a different archaeological object and take you on a journey into their past.
00:00:17
Speaker
Hello, and welcome to episode 27 of Tea Break Time Travel. I'm your host, Matilda Ziebrecht, and today I'm savouring a Clutie Dumpling Black Tea, which is really good, actually. It's a lot more surprising than I thought. And the person who sold it to me, so I recently visited Scotland, where my parents live, and I went to the Aboyne Highland Games, and there was a fantastic stall there.
00:00:40
Speaker
selling tea. So of course, you know, I see a stall selling tea. I go over to the stall selling tea. And I went over and I had a look and they had a very wide range of really cool looking teas. And this one just popped out at me, Clutee Dumpling Black Tea, and I smelt it and it just sm smelled of spices and deliciousness. So I thought, yeah, I got to try this one. So I got that one and they suggested having it with warm milk. So not with hot water, but with hot milk. And my goodness, it's delicious. It's so good.
00:01:08
Speaker
Clutey Dumpling, by the way, for those of you who don't know, is a Scottish dessert. It's a bit like, for anyone who's had sort of a Christmas pudding, it's kind of a thick fruitcake. So it's made with, with suet and with dried fruits and flour and eggs and everything, and sort of flavoured with milk. And it is, it can be nice and sort of moist, but sometimes it is a bit dry, I'll be honest. And so quite often you'll have it with cream or with custard or or something like that. And it's very, very good. So that's what a kluti dumpling is. And it's also usually got some kind of spices in it as well. Anyway, that's what I'm savoring
Introducing 'Tea Break Time Travel Training'
00:01:43
Speaker
today. And today is a very exciting episode because it is our very first episode of Tea Break Time Travel Training, where we're going to have a look at all of those kind of theories and methods that you really need to have under your belt.
00:01:59
Speaker
if you're a seasoned time traveller, and of course, if you're an archaeologist. So I'm going to try and give you a little bit of the theoretical and methodological background of the kind of research and the objects and the the topics that we're covering in the sort of guest episodes, which will as always happen on the fourth Tuesday of the month. So these ones will be released on the second Tuesday of the month. And on the fourth Tuesday of the month, we'll have our regularly scheduled guest episodes. So where shall we start? with this tea break time travel training. Well, let's imagine you've gone back in time, you're looking at all these fantastic objects, all these fantastic things, but you want to know, is this actually authentic? What if someone else has traveled back in time and has put this stuff here before me? How do I know that this is the real deal?
Dating Methods: An Overview
00:02:45
Speaker
And of course, one of the easiest ways to know is by seeing how old those things are. Because if you've gone back to the year 1300 and you date something and it's also dates to the year 1300, you can be pretty sure that it's authentic and it's from that time period. By the way, if this idea and this conundrum is something that interests you, I would recommend checking out episode eight of And My Trial, where we look at time travel and the authentication of materials. Just shameless self-promotion there for my other podcast that's on the Archaeology Podcast Network.
00:03:15
Speaker
So, yes, the easiest way to see if something really has come from the past is to check how old it is. So, there's many, many different ways that you can do this archaeologically. There's lots of different methods you can use, and these methods depend on how old the sample is. ah They depend on the material it is. They depend on the context. They depend on how much of the sample it is um and how, I guess, accurate you want to be in terms of, yeah, various different aspects.
00:03:41
Speaker
So we're going to be covering a couple of different ones in the first few months. And we're starting today with one that is definitely one of the most commonly used within archaeology, I would say. And it's probably one of the most better known outside of the field of archaeology as well. I feel like most people will have heard of it and it is radiocarbon dating, otherwise known as carbon 14 dating. And radiocarbon dating is one of these things that in principle is very easy.
00:04:06
Speaker
Radiocarbon dating carbon is in organic remains, a i.e. any sort of material that has come from something that was once living, so once held carbon, so bones, leather, plant material, wood, anything like that. So stone, for example, you can't date with radiocarbon because it doesn't contain carbon, or at least not enough for you to be able to date it. And by looking at how much carbon is in the object, you can see how old it is.
00:04:35
Speaker
That's not really it, though. That's very, very, very oversimplified. um And it's a little bit more complicated than that. And quite a lot of people, I think, don't really understand how it works. So I'm going to attempt to explain it in as simple terms as possible. So of course, as always,
00:04:54
Speaker
I have done my research. I have looked things up. It is all presented here. But if this is a topic that interests you, I would definitely recommend reading further and chatting to more people who have spent their whole life researching this because I am an archaeological scientist. I did do methods of artifact analysis, which included learning about dating methods. So I have done this in my studies, but I do not do this on a daily basis. So quick caveat as to the amount of detail that I can go into. Also, I'm only going to be doing 20 minutes or so. So there's only so much detail you can go into in 20 minutes. So radiocarbon dating, also known as carbon-14 dating, which I hear you cry. What is carbon-14?
Radiocarbon Dating Explained
00:05:35
Speaker
Well, carbon-14 is an isotope of carbon.
00:05:40
Speaker
Those of you who did, I guess, high school chemistry or physics will know that an isotope is versions of an atom that have the same number of protons but different number of neutrons. So, for example, carbon-14 has six protons and eight neutrons. So, this means the isotopes of an atom will have the same chemical properties because they have the same the same number of protons, but they will differ in mass, so in weight, and therefore in physical properties. So, there are, for example, stable isotopes. So, carbon has three kind of more commonly known isotopes, which are carbon-12 and carbon-13 and carbon-14. 12 and 13 are both stable. This means that they do not emit radiation. They just sit there and they're cool and they're chill and they just kind of stay the same. Carbon-14, however, is unstable. It's like that cousin that just went a little bit off the rails.
00:06:31
Speaker
This means that they emit radiation. And by the way, carbon-14 was sort of discovered and these properties of it emitting radiation and it being unstable was discovered in early 1940 by Martin Cayman and Sam Rubin.
00:06:45
Speaker
and The discovery of this led to a chemistry professor who was based at the University of Chicago called Willard Libby looking at this kind of instability and this radiation and this decay, which decay basically means that the isotope turns into something else over time. So in the case of of carbon-14,
00:07:08
Speaker
as it releases radiation, it decays, it turns into nitrogen-14. Just a little side note, that's not really important detail to remember necessarily for this, but it's just important to keep in mind while you're taking this in. And this decay is something that's very important. Now let's go like back a little bit first. So carbon-14 the isotope is basically created up in the stratosphere and then kind of moseys its way down into the atmosphere where it is then absorbed by living beings in the form of carbon dioxide.
00:07:43
Speaker
So we all remember this from biology class, I'm sure, that carbon dioxide is part of that kind of living cycle with oxygen and breathing in, breathing out, all of that kind of thing, doing photosynthesis if you're a plant, things like that. So it's an important part of the living organism. And tests and research have shown that kind of the average concentration of carbon-14 that's in the atmosphere, after having been created by in up in the stratosphere and sort of moseying down, that concentration of carbon-14 is pretty much equal to that that can be found in a living being. So what does this mean? This means that basically living beings are regulating intake and outtake of carbon-14 in sort of equilibrium with the surrounding atmosphere. So that also means though, that means that the the the carbon-14 levels in the body are sort of constantly replenished even when they're being used up, right?
00:08:33
Speaker
But what does that mean then when the living being dies? Because then they're no longer taking in new carbon-14 to replenish those kind of reservoirs within it that have been depleted. So that means that's where this decay comes in.
00:08:50
Speaker
because it emits radiation, it decays, and we know that carbon-14 has a half-life of about 5,600 years. So, this means that after that time, around 5,600 years, a non-living organism will have half the amount of carbon-14 in it compared to when it was alive.
00:09:09
Speaker
So in other words, a creature that died 5,600 years ago will have half as much carbon 14 in it than one that is alive today. Again, this is pretty simple, simplified, like the the actual calculations and everything like that is a lot more complex, but I didn't want to, it's a bit difficult to do on audio form without actually showing the calculations. And if I'm perfectly honest, there's a lot of numbers and signs and sigmas and and everything in there, which I didn't want to go into too much detail about.
00:09:36
Speaker
so By using this half-life, Willard Libby, remember Willard Libby, the chemistry professor at the University of Chicago in the 1940s, realized that you could work backwards and you could see, okay, how much carbon-14 is left in this organic so material that you have, be it bone, be it leather, be it paper, be it wood, whatever.
00:09:59
Speaker
How much is left in that? Let's calculate backwards based on this rate of decay, based on this half-life of 5,600 years, and see therefore how long this creature has been dead.
00:10:12
Speaker
And that is how you can then see how old something is. There are, of course, some issues with this, and we're going to get to that in a second. But interestingly enough, so Willard Libby actually won the Nobel Prize for his work on radiocarbon dating because it was such an amazing kind of discovery and such an amazing idea that it really just revolutionized archaeological research completely. Because before then we had to rely a lot more on typologies, we had to rely on dendrochronology, which I'll get into in a different episode, and we had to yeah sort of compare things a lot more. Whereas this way you had a method of looking at an individual sample and ascertaining how old it was. So it really was game-changing in terms of archaeological research.
00:10:58
Speaker
And my favourite fact about this, by the way, so in order to kind of test whether this this was actually valid, whether it was accurate, whether Libby, of course, tested lots of known samples of known age and was able to demonstrate that like, yes, look, if we use this method, it's it's very accurate in determining how all things are. He also looked to check, like, look, you can see that the older a sample is, the less carbon more carbon-14 it has, the less carbon-14 has, sorry, getting confused. So if a sample is older, it it will of course have less carbon-14 in it because it will have been decaying for a longer time, right? And so one of the ways that he did this, he did a couple of different tests and experiments, but one of his tests was looking at the gas methane, which contains carbon, and
00:11:41
Speaker
One of his samples of carbon from methane, he extracted from kind of natural gas, were fossil fuel, which if you think about the time that it takes to kind of create that fossil fuel, the carbon-14 should have decayed long, long, long ago. It should have little to no carbon-14 left. right and His second sample that he used as a comparison, he wanted a modern sample of methane. Where do you go to get a modern sample of methane, especially if you're in the city of Baltimore,
00:12:06
Speaker
You go to the sewers and you get it from two. So, according to his hypothesis, that should be extremely rich in carbon-14 because it's just been produced by humans. It's still pretty fresh. And that's exactly what his results showed him as well. So, the ancient met methane had no carbon-14. However, the methane that had newly been excreted by humans was pretty rich in carbon-14.
00:12:32
Speaker
So, this is a very interesting fact that, by the way, it was featured in the book by John Mara, Hot Carbon, Carbon-14 and a Revolution in Science. So, yes, that's my favourite little fun fact. So, that was a lot to take in. Hopefully you're still with me. Let's quickly top up our tea and we can continue with looking at the practicalities but also, of course, the issues of radiocarbon dating.
00:12:55
Speaker
Welcome back,
Practical & Ethical Considerations
00:12:56
Speaker
everyone. Hope you're feeling refreshed. Hope your brains are still buzzing with excitement about learning about all of this radio garden dating. And I hope that it is making sense. I hope that you understand how it's all sort of working. It is sort of quite a simple concept in reality, but it's sort of complicated to think about, I think, is is is these things. And if you reason it out and kind of think of practical examples, then it makes more sense.
00:13:22
Speaker
So hopefully that's what I've been trying to do. If anyone has any further questions, by the way, if you have any things that you think I haven't covered, please do let me know. You can email me, you can send me messages on Instagram, you can contact me via the APN discord server. So please do get in touch if there's things that you feel that I haven't covered or the questions that you still have. So.
00:13:42
Speaker
In this segment, we're going to look at the kind of practicalities of radiocarbon dating and, most importantly, the issues of radiocarbon dating, because it's very important to understand the limitations and the problems that you might encounter with any method that you use in archaeology.
00:13:59
Speaker
so First of all, how does radiocarbon dating actually work in practice? so As we mentioned before, the whole point of radiocarbon dating is to look at the decay and the half-life of carbon-14. Carbon therefore has to come from an object that held carbon. Most of the time, this is living objects who have interacted with the atmosphere in some way. right That's what you're looking at.
00:14:21
Speaker
So, you're looking at things like leather, you're looking at things like plant material, you're looking at bones, you're looking at wood. Antler can sometimes be as well. Of course, what's important though is that you have to keep in mind that the thing that you're dating is when the carbon-14 stopped being absorbed, right? And that it was just decaying. So, that's always something to keep to keep in mind. We'll come back to that in a second.
00:14:44
Speaker
but So you have to have your organic material sample. It has to be a clean sample. It can't be contaminated by something from anything else. If you're eating like a tuna sandwich and then your tuna gets on the sample, then they'll be dating the tuna instead of the sample. So important to keep it clean. Also important to have it from kind of a known context, because most of the time when you're sending off samples to the lab,
00:15:07
Speaker
to be dated you want to know how old it is because it's being sitting in a nice little stratigraphic layer so it's on a certain point in your site and you think aha that means that everything else that is on this layer in the site must be the same age as this object.
00:15:22
Speaker
It's also quite a big assumption, so you need to be pretty certain that it's all from the same layer. So that's why you're dating it. That's why you want to know how old a particular object is. Because if you say, okay, well, this this layer of dirt has two bits of bone, 50 ceramic shards, 100 flint axes, and half of a house base.
00:15:42
Speaker
Then if you find out how old the bone things are, you'll also know how old everything else is because the assumption is that they were all deposited there at the same time. Again, this is a pretty big assumption, so you need to double check that this is actually the case.
00:15:54
Speaker
So then you send them off generally to a radiocarbon dating lab. Now I've had some questions about whether private people can also send off samples to a radiocarbon dating lab. The answer is it depends because sometimes they do and they might just charge a little more. So just to give a round figure, I looked up a couple of different dating labs and prices range around a couple of hundred euros per sample, but they generally do charge more if it's a private sample.
00:16:21
Speaker
and The reason is because most labs will happily accept samples intended for kind of academic and scientific research, but the problem with accepting samples from private individuals is that you're not really sure what that date is going to be used for. and There's the ethical issue of the sale of antiquities on the black market.
00:16:39
Speaker
So it might be that people are sending something in in order to work out how old it is, in order to then be able to sell it, which that's not the point of of this research method. That's not the point of archaeological analysis. I know a lot of people seem to think that archaeologists get money from the objects that we dig up. We don't. like We never get money for them. We get our money from, well, if we're in commercial archaeology or sort of cultural resource management, then it's like a normal job, right? We get an hourly pay for them for the work that we do, but we don't get like bonuses if we find specific objects or anything like that. like You'll get paid the same if you find a ditch or if you find like a golden axe. it's It's pretty much the same. so That's sort of the commercial side of things. and On the academic side of things, usually you get paid either because you've got some sort of position at the university, so maybe they're paying you to do research.
00:17:31
Speaker
or maybe they're paying you to teach, so you're basically working as a lecturer, or you might get a grant, which is for a specific research project, but that money then goes pretty much back into the research straight away. So you do get some kind of salary, but you're mainly paying for like travel costs, you're paying for equipment, you're paying to employ PhD students or other people or assistants, teaching assistants, you're paying local communities to be able to hire areas or resources from them, for example, but you won't dig up an object and then send it off and get money back from the government or something. Like that just doesn't work anywhere in the world.
Limitations of Radiocarbon Dating
00:18:07
Speaker
And so that's the problem with going back to then this is that, you know, that's where then the sale of illegal antiquities comes in because some people do do that, but they're not.
00:18:16
Speaker
archaeologists, or well, sometimes they are, but they're not good archaeologists, because that is not what you should do ethically. That is extremely unethical practice. And if other archaeologists found out you were doing that, you would immediately be, I mean, struck off is not the term because you can't strike people off, but you know what I mean.
00:18:34
Speaker
So anyway, point being, if you're a private individual and you're sending off something to get you want to send off something to get dated, it's unlikely that a lab will accept your sample because of those ethical issues, because they'll be worried that the dating the date that they will be produced will be used in an unethical way to sell an object. So it's something to keep in mind.
00:18:58
Speaker
And then, ah it again, the time varies on the lab. Sometimes it's a couple of days, sometimes it's a couple of weeks. um You get back some dates. Now, these will not be like the 4th of September, 1782. You can't be that accurate. There'll always be a window with sort of margins of error. They always have standard deviations with them. And depending on how old your sample is, of course, these margins of error can be sort of bigger or smaller. So you usually have a date range. And you'll see that if you read papers, it'll be something like 2650 bp plus minus 450, which basically means 450 years is the kind of margin of error on either side of that. So something to keep in mind.
00:19:39
Speaker
So, let's have a look at the kind of issues of carbon dating. So, first of all, what can we actually use carbon dating for? We've already said it can be for organic materials, but how old can we actually date? Because, as we said, there's this half-life of 5,600 years And you can still date things that are older then than 1,200 years. at one thousand two hundred years sorry you know It's not that the carbon is completely depleted, it's just that that's the kind of rate of decay. you know So you can accurately date things, and there's a bit of debate about the exact date, but generally you can accurately date things up to around 40,000 years old. But after that point, there's not really enough carbon left
00:20:26
Speaker
in the material to be able to accurately date something. And the assumption is that past 60,000 years, it's pretty much impossible because there's usually no carbon left to kind of look at. So it's really hard to work out how old something is if you only have a tiny, tiny, teeny sample. So that's also something to keep in mind if you see any studies that say, oh yes, and we radiocarbon dated this and it's 120,000 years old. That's rubbish because there's no way that there would be enough carbon left in that sample to be able to actually date it.
00:20:56
Speaker
When you send off your samples, you usually need a decent amount of material, by the way. This is something, maybe I should have included this in the practical things, I've listed it here in my issues um list. But it is a bit of an issue, I suppose, because archaeological dating methods are quite often destructive. So that means that you need to actually destroy the sample that you're sending off.
00:21:15
Speaker
which is a bit of a problem. So that's why, for example, you would never send off like a nice little statue or a little needle or anything like that. Usually it's like a random bit of bone or a random scrap of something. You don't want to send anything that's too valuable in itself. So because quite often you need to send between sort of 10 to 100 milligrams of material. And there's other dating methods which need a lot less. And there are actually some newer methods, like AMS, which enables smaller sample sizes, but we'll I'll deal with them in a sort of future episode. But the point is, you you are required to send in material that you then you won't get back. right You'll just get the dates back. So that's also sort of a bit of an issue of carbon dating, if you think about it, because you're limited in in what you can actually send, because it has to be something that you're not worried about losing, that won't provide any other information about the context of the site.
00:22:03
Speaker
And something that I sort of mentioned a bit before, just because an organism died at a certain time, that doesn't mean that you can necessarily date a site to that same time. So for example, I gave the, i I said that if things were in the same layers, right, then you could date those things and then you could date that layer and then you could say, ah, that's the time that that site was. However, imagine that there was a tree that was cut down and then 200 years later, it's used to build a house.
00:22:33
Speaker
Like, you'll when you're dating it, you're not going to be dating the point of building, you're going to be dating the point of death of the tree. And also, for example, bones that might have been, I don't know, passed down through generations, if they're bone necklaces or if they're... i don't know I don't know why you would pass down bones through generations, but it's just something to keep in mind. Also, for example, linen is technically an organic material, but when you date it, you're not dating the time that the linen was made or the dress was made. You're dating the time that the flax was harvested in order to create the linen, because that's the point that the flax died and that's when the decay started. So, you need to kind of keep in mind what that date is that you're getting back um as well.
00:23:15
Speaker
So that's also just a little bit of an issue that you need to think about with those things. And then there's two pretty big issues that come up a lot in
Accuracy Challenges & Calibration
00:23:24
Speaker
radiocarbon dating. So we already mentioned sort of the oldest date that you can do. So 40,000 years accurately, 60,000 years at a pinch. So also the newest dates that you can do. It's sort of generally assumed that post 1950,
00:23:41
Speaker
it's pretty inaccurate to do radiocarbon dating. Why is this? Well, in the 1950s, there was a lot of nuclear testing. And what does nuclear testing do? It creates radiation in the atmosphere, and it basically means it meant that suddenly the levels of carbon-14 in the atmosphere increased dramatically, like a lot more than there were before. So,
00:24:04
Speaker
That means that anything kind of after this time in terms of of the atmosphere, it's not because the the whole assumption of the radiocarbon dating, if you remember, was that the there's a bit of an equilibrium between the atmospheric levels of carbon-14 and those in living organisms. But if then you have a sudden change in the atmospheric levels of carbon-14, this will then affect the accuracy of any dating that you do because you're always comparing it to that atmospheric level.
00:24:31
Speaker
so This can still be kind of taken into account. so This therefore means that any radiocarbon dates from the past still have to be calibrated against a reference standard from the year 1950. That reference standard is calculated from samples of oxalic acid at known concentrations of carbon-14. So, that it's sort of it's compared to that point where suddenly you have this increase to make sure that any inaccuracies or any kind of anomalies from that are taken into account. So, you do have calibration in radiocarbon dates as well, so that's something that happens.
00:25:04
Speaker
Interestingly enough, by the way, this whole the nuclear testing 1950s is the reason that BP came about. BP, I don't mean the oil company, I mean before present. So you might be familiar with BC before Christ and AD. And one alternative that is often used is BP before present.
00:25:24
Speaker
And what is present? Present is the year 1950. And this is because archaeologists needed something that would define dates before that point in 1950 with this reference sample against which everything is calibrated. So when you see samples saying before present, they don't mean literally before present as in like now the present day, they mean before 1950.
00:25:45
Speaker
And originally, it was only supposed to be used for those dates achieved using radiocarbon dating, but now it's sometimes used it in other contexts as well. So there we go. Fun fact for you. so That's kind of one of the major issues of it. Another major issue is what's known as the marine reservoir effect. so Remember that we are going on this assumption about carbon-14 being in the atmosphere, being absorbed by animals and creatures and plants and everything, and that's the sort of baseline for our rate of decay and our half-life.
00:26:18
Speaker
So the atmosphere and the oceans and the biosphere, they're referred to as radiocarbonate reservoirs because they contain and they store carbon-14. So when you consider the oceans,
00:26:31
Speaker
it's quite different from the land because on the land, you have the carbon-14 that's coming down from the stratosphere and being you know carbon dioxide and the carbon-14 in organisms, but the oceans, there's also another kind of carbon-14 that's created in what is called the deep ocean.
00:26:49
Speaker
So, this means that organisms that live in the ocean, or even in other marine environments, there's been some interesting research on that, won't necessarily have the same concentrations of carbon-14 as those living on land, because they're absorbing their carbon-14 from both the atmospheric and the deep ocean reservoirs.
00:27:08
Speaker
And this is shown to kind of affect the accuracy of the dating. So, generally, samples from marine-based organisms often end up being dated as around 400 years older than they actually are. So, there is a way to calibrate for this, of course. So, either you just Yeah, take that into account, although that's pretty inaccurate as well. But you can also just avoid marine samples, so quite often you want to make sure you get a kind of terrestrial animal or or plant. Although, just a quick side point, it's not necessarily limited to those creatures living in the ocean. But for example, if you have ah a terrestrial animal who has a purely maritime diet, so like a polar bear, for example, they will also demonstrate an older age than they really are, because they have
00:27:52
Speaker
the same kind of intake of of the carbon-14 through their diet. So because of the marine reservoir effect. So you really need to know what the bone is or or what it is that you're dating and whether they would have been affected by by this marine reservoir effect. So another way to kind of account for the inaccuracy is to get a value for the local reservoir concentrations so that you can see already by how many years it is offset in that particular site. And then you can adjust any kind of dates you get back accordingly But this is of course very dependent on the on the data and on the samples um that you have. But yeah, so that's something that a lot of people have to take into account. And for example, I know that in in the Arctic, it's a lot stronger, there's a lot more offset with the marine reservoir effect than other oceans just because of
00:28:39
Speaker
various things with the atmosphere. so Because you're so dependent on the kind of concentration of carbon-14 in things, you need to make sure you understand what the levels are in the place that you are as well, um and in the kind of context or the reservoir that you're looking at.
00:28:54
Speaker
as well. so yeah Those are a couple of the issues and the things to keep in mind. Luckily, we recognise these issues and luckily there's lots of research being done on how we can kind of account for the inaccuracies and the anomalies that are created through these issues. so Quite a lot of the time, they're not even really a problem, they just have to be calibrated or accounted for.
00:29:16
Speaker
But again, it's just something to look out for if you're looking at other studies and things as well. Check that they have actually calibrated for that, and they have actually accounted for that, because if they haven't, then they might have very inaccurate dates. So that brings us to the end of this quick introduction to radiocarbon
Conclusion & Next Episode Teaser
00:29:33
Speaker
dating. I hope that it was interesting. I hope you learned something. I hope things are a little clearer, and they're not just more complicated than this. And yeah, next month we're going to be looking at a different dating method. Haven't quite decided which one yet so we'll have to see what inspires me over the next week or two. Keeping my eye out by the way for this month's guest episode which will feature Dr. Adrian Maldonado and look at the Galloway Horde so that will be out as always on the 4th Tuesday of the month.
00:30:00
Speaker
So I hope that you enjoyed our training session today. If you want to help support this show and all the other amazing series that form the Archaeology Podcast Network, you can become a member. You'll be helping us to create even more amazing content. You'll also have exclusive access to ad-free episodes and bonus content.
00:30:18
Speaker
For more information, check out the homepage at archaeologypodcastnetwork.com. I hope that you enjoyed our journey today. If you did, make sure to like, follow, subscribe wherever you get your podcasts, and I'll see you next month for another episode of Tea Break Time Travel.
00:30:35
Speaker
This episode was produced by Chris Webster from his ah RV traveling the United States, Tristan Boyle in Scotland, DigTech LLC, Cultural Media, and the Archaeology Podcast Network, and was edited by
Production Credits & Contact Info
00:30:47
Speaker
Rachel Rodin. This has been a presentation of the Archaeology Podcast Network. Visit us on the web for show notes and other podcasts at www.archpodnet.com. Contact us at chris at archaeologypodcastnetwork.com.