 Okay, well thanks for that introduction. So over the next 15 minutes or so, I want to take you through the methods that Derek and myself employed to date the Doggerland Cores. Before I do that, we just want to acknowledge some people. Yeah, in St Andrews, I have to thank the technical support of Rebecca Neyland-Ayush, and that Rebecca deserves a special mention because she was an undergraduate that won a Carnegie Trust scholarship to look at some of these materials. And over in CERC, we'd like to thank the Hall of the Rideau Carbon dating team. So, need to reconstructing the paleogeographies and environments of Doggerland is a robust chronological framework. And this has been constructed here from at least 22 of the 109 recovered cores. And now we've got a very extensive datasets. So we've got 178 real carbon constraints, 139 OSL constraints, and they are augmented by luminescence stratigraphies constructed from both proxy and calibrated data. So if it's not already apparent, Derek, he leads the Rideau Carbon and I read the OSL. So what's more, we've got a great spatial distribution of core with a representative selection from across the Southern North Sea, including the Southern River Valley we've heard about this morning, the Silver Lake, sorry, the Silver Pit Lake, and then also Brumbank. And moreover, we've got a great temporal distribution which spans everything from the Lake Glacial up to the final inundation. And I've got this as an exclamation mark here because you can see in some of the cores, we have evidence of a slightly later inundation for Doggerland. But as you can imagine, constructing these chronologies hasn't been without difficulties. So in regard to OSL dating, it's the sheer number of environmental settings that we attempted to investigate that has presented a challenge to dating. And this has been compounded by the fact that we're examining sediments from core. So I don't have the same quantities of sediment that I normally would use in the study. But if I'm on the right then, it shows how the range of human environments that we're interested in, where they have a range of environmental conditions that are conclusive to dating. And also what it shows is that not all the sediment has the same response. And as you can imagine, we're covering a massive area here. So the lithologies are very different and the minerals within them are very different and they have a range of luminescence responses. So again, I've attempted to show that this on this diagram to the right. A fourth challenge we have is how do we reconstruct those rates to the sediments within these cores. But thankfully, we do have some solutions. One of these is the construction of luminescence stratigraphies. And the second is we can look at down profile trends in radonuclide concentrations so that we can model environmental dose rates as robust as we can. So we're going to demonstrate the processes by sorry the methods by looking at two cores. In terms of OSL, we're going to concentrate on one a and then when we come to the radio carbon, we're going to concentrate on 34. So you've heard both those cores that this morning, one a is located at the head of the Southern River Valley. And it had interest to us because this is where the potential tsunami was it's worth. So this is what I show on the on the left. This is a photo of the core. It's been identified by marking Bates. Just to point out four and seven, we know that they are titled mud flats. And in fact, and this is interrupted in five and six by these Shelly gravels. And it's that interval there that's potentially relates to the story of the tsunami. So I've shown this core schematically in the center here with units one to seven in their pale environments there. So let's have a look at it. So there's that schematic. So the first potential solution is looking at luminescent stratigraphies. So what I show here, this is depth and core. And then this is the net signal intensities. What is a net signal intensity? Well, this is shown on the right here. So this is two samples. We have a young sediment sample and an old sentiment sample. And what I'm just showing is one measurements cycle with a portable work cell unit. What we have is luminescence on the vertical axis. In time on the horizontal axis. And we choose to look at two stimulation methods infrared. So that's our IRSL and our blue light stimulated. So that's our OSL. And I think it's quite apparent. You can see that young sediment has a low luminescence count. And this older sediment has a higher luminescence count. So what does that mean for this core? We can see that each of these units then is characterized by a distinct set of luminescence characteristics. And importantly, you can see the stratigraphic breaks, which relates to temporal breaks and time within the core. What it does show is we have very complex depositional sequences. So the next stage is to take those samples from just that first proxy record that we had it. We collected a core sampling to the lab. So we take each of those samples through some simple analytical procedures. So that for each sample we have an apparent dose. So this is comparable to the burial dose that you've heard mentioned in OSL data. So I'm just going to simplify this and just return to that one plot. The reins in stored doses isn't too relevant, but what I just want to draw your attention to is where we have stratigraphic progressions. Because that tells us something about sedimentation. It tells us if the sediment package is consistent and coherent. And where we have temporal breaks, because that's where we have our unconformities. So that's great. We can start to identify specific horizons in the core that we wish to date. But again, now you go, we have the complex depositional histories that we still need to interpret. So I'm just now going to zoom in on these two units and show you what that data looks like. So that's it here. There's our relative plots and then our calibrated plots. I think you can see that there's at least three couplets in here going from low to higher dose, low to higher dose, low to higher dose. So that's what we're seeing in the luminescence. But what do we see in other proxies? Well, this is some of the inferences from the core scanning. And this is a similar depth. So if I just do this and overlay this on top, well, this is potentially three waves within that deposit. And we're seeing it both in the luminescence and the geochemistry. So with construction, constructing these profiles, we have a good sense of the sedimentation histories. So we know where we are. So we can produce in samples where we think we'll get good dates. But the next challenge then is reconstructing the dose rates. And how do we go about doing that? We've got various methods available to us. We can directly measure radonuclide concentrations by a supermass or a gamma spectrometry. But we can also use core scanning to look at down core variations. So the sum of all this is we can be quite robust when we say we have a dose rate at any one point, sorry, any one depth in the core. And the third solution that we have is we can look at how the different samples relate stratigraphically. So this is a depth model being put together by Derek with individual OSL constraints soon. And their position is in sequence. This is great and interesting. You can see what the potential horizons where we've got incomplete bleaching of sediment. And if your sediments incompletely bleached, you'll have an age overestimate. And also shows done here that we had a radio carbon constraint from a shell. And in this case, that is residual and overestimating the age. So in terms of ELF 1A, we're able to have a robust chronology through that unit that spans from 6000 at the top. This is the base of the mudflats down to 9.2 base and the high energy deposits. They come in at between 8 and 8.2, a mean age of 8.1. So yes, they are a contender for storage. So that first part of the talk talked about the OSL. Now we're going to look at the radio carbon chronologies. So as a OSL, it has its own set of challenges. So tapponomic and technical challenges can impact the development of radio carbon based chronologies. What's important for dating these units is that we have a tight security on the material that's being investigated. And how we've gone about that in this project is we've looked at dating multiple fractions. So we've looked at both the humic acid and the human fraction. So both Ben and Tom alluded to this earlier. So the human fraction, for those that don't know, lets any organic matter that's recovered. Whereas the humic acid is a byproduct of the humification process. So the human fraction is acid and upline soluble, whereas the humic acid precipitates out of a highly acidic solution. So it's possible to separate the two in the lab. Why is that important? Well, the human fraction can be affected by tapponomic processes and it might introduce residual materials to the core. Whereas the humic acids will remain in solution in a weak acidic environment and they can be somewhat mobile through the profile. But what's great is when the two fractions yield statistically consistent dates, we can have increased confidence in the security of the samples and the robustness of the chronological model. So we're going to return to ELF 34, which is the core that both Ben and Tom talked about. And in this first slide, we're going to look at the relationship between the two dated fractions. And you can see them coming through in pairs here. You can see for the top part of this up to depth of 172 centimeters, they've got good consistency. So that's great. Whereas beneath that, the two fractions diverge. When we resolve these potential conflicts, we can then reconstruct age death models. So here's the age death model now for 34. What's really great about this is it removes us thinking about individual constraints on certain horizons in the core to be able to talk about chronology for the whole core. So we can query this model to date specific events in the chronology. So just to highlight this and this is referring back to Ben's presentation, we want to date for the start Holocene in the start studio. So there's the query and it comes in. So we have a date for the start of the studio in 34 to between 13 and 12,000. And you can read the rest of the dates there. So we realized when Tom was giving his presentation that we've mistook the description. So we've taken the base of the peak to be the base of pollen. So we can exclude that often date and we'll come back to that. So also great about having the two methods, the two chronological methods as we can compare in contrast. So with the reference to one a I showed that the radio carbon date was residual. The OSL dates from 34 were there the opposite they've underestimated the correct deputational age. Why is that when OSL dating I'm sampling the mineral rich horizons, and I don't tend to sample the organic rich horizons. Those organic rich horizons will have a lower dose rate than the horizons I've sampled, but because of my dose rate measurements are taking on the mineral rich horizons. I have overestimated my dose rates, which has resulted in underestimation in age. So, because we have such a large data set, we can apply these methods across the course, and we can be sure when we say we have a date or a specific court that we do. So that's my 15 minutes up. So to conclude, I thought I'd just throw up the slide at the start. And see, we have built a robust chronology for those 22 investigated course. And this has provided the temple framework on which to test the period geographical environmental reconstruction. So I can take any questions. Well, thank you very much Tim. I'm checking on the chat box. We haven't had any questions come in yet, but if anybody does now would be a good time. Well, we're waiting for that actually. Oh, hello. So we have from Michael Grant. With pet the pair dating, have you been able to model the effect of changing moisture content over the burial period. Yeah, we've done that to some extent just on OSL side. Now we have the, the two data sets both radio carbon and OSL. We're going to look at modeling the age death models for both. And then we can start to look at how much. Well, what you'd have to do to change the moisture content to bring it in line with the the radio carbon. So yeah, that's that's the next stage. Okay. And from Irene gosh, why I hope I got that pronounced correctly. In the first core you showed two outliers in OSL dates. How certain can you say this is due to incomplete bleaching is the question. Yeah, so in general, it's easier to see a situation where you have older sediment coming in and not seeing daylight than younger material coming into the profile and working its way down. More so because we have our profiles. So we can say if we think that there is an evidence of material moving up and down a core. And that allows us to exclude all the dates that would be younger being, is it being too young because the material working in. And it's more likely that the material sitting to the right so order and age is residual. Okay. We have a couple more questions coming through. Can you model the dose rate from your extensive scan data to correct the age under estimations. Yeah, that's one of the next stages. Yeah. And Zoe, Zoe out from. Did you consider radiocarbon dating plant macros as well as comparing them to the human and humic fractions. Yes, we did. And there's Derek. I'm going to highlight it earlier today that the, there's quite a bit of compression and actually there really weren't any plant macros that were being identified. Kind of within the Pete so we were stuck with humic and human fractions. Okay, and we've got one more question here from Michael Grant. Did you attempt an EK felt spa dating. No, we haven't done. Short and sweet.