 Okay, thanks very much. So like Ben just said, I'm going to take you back to the North Sea, we're going to go a little bit further than the southern river here, but it's kind of a similar story. I'm going to do this the old-fashioned way and show you the film credits first. As you can see, there's been a whole lot of people that have helped out either with the collection or the data, with the data interpretation or with the core analysis and just with the general discussion. So there's only three people on the front page, but there's a lot of work that has gone into this. A little bit of background of how this fits with the larger ELF project. In about 2015-2016, we had two PhD students at Gantt University who were looking at seismic data and multi-beam data of the Southern North Sea. So we had David Garcia Moreno and he was trying to see if there was evidence of this LGM lake to the east of Lagerbank. And then there was Michael de Gled, who was trying to kind of see what was happening with this deep channel and how it fit with what we see in Belgium. So they were trying to answer some geological questions, because it kind of became quite clear that some of the geological questions also had archaeological implications. So ELF had already started at that point and there was a quick meetup between Gantt University and Bradford, just a meet and greet. And it just kind of became obvious that there should be a collaboration on some of these questions. So later on we also had some Dutch institutions and universities joining a consortium and then Leeds University also became part of it. And we now have this UK Belgian Dutch consortium who's working on this unfunded project named Deep History, Revealing the Paleo Landscape of the Southern North Sea. And this is kind of where this research fits into. I'll tell you in a minute why we decided on the Brown Bank, but let's start off with the strategy we're trying to follow. We've kind of heard this come back a few times though in different presentations in that we start with a regional scale answering some of the geological questions and then hope to go to a more local scale and hoping that that will help us to answer some of the archaeological questions. So where is the Brown Bank? So the Brown Bank is kind of just in Dutch waters, it's this ridge here and I'll zoom in in a minute. But what this picture is showing is the no prehistoric sites in the North Sea and on the coastal sites as well. And here you see this deep channel and you can see prehistoric sites on the western margin and you can see sites on the eastern margin and this is kind of the area where there's quite a few sites that are concentrated. So I'm going to zoom in to where this circle is here and show you where the Brown Bank itself is. So here again we have this deep channel, then we have the Brown Bank, it's actually a sand ridge that is sitting up about 20 meters above the current seabed. The seabed itself is about minus 30, minus 35 meters and then we have this deeper scour pit here which is sitting at about minus 45 meters. And you can see these sites kind of dotted across the seabed. Now these are not accurate positions, these have come up, these sites of these artifacts have come up from fishermen trolls and we don't know exactly where they were trolling or how long the trolls were. So these are just kind of rough estimations of where these sites could have been. What kind of material have we got? We have bow material which has been lovely decorators, we have perforated tools, we have a jaw, we have a piece of skull. So all of these are kind of early mesolithic and then we also have some neolithic axes here. As well as archaeological material there's some fallow remains. So in this scour pit here there have been quite a bit of mammalian fossils, especially mammoth bones and elephant bones. These are older than the archaeological material we've got, these are early to middle Pleistocene. Further to the south there's also been quite a lot of material that has been dredged up, that goes back to the early middle Pleistocene period. As well as these older materials we also have here where these stars are, we have several blocks of peat that have been dredged up, the so-called moorlogs. And Saskia Jelgesma in 1960s has analysed these and looked at these and these date back to about 10,200 to 9,400 Kbp. So the facts are that we have definitely two terrestrial landscapes that are somewhere preserved in the Brown Bank region. We have the older early metal Pleistocene one with the Cromerian faunal evidence and then we have our early Holocene or Mesolithic landscape where we have archaeological and geological evidence. For this talk I'm going to concentrate on this early Holocene Mesolithic period. So the questions we had is where is this material actually coming from? Is any of it still preserved in and then what is the significance of this area for the North Sea archaeological story? So it was kind of obvious that we had to go and look in the Brown Bank area and do some more gearcheological investigation. Just to put this in context here you've got the global sea levels for the last 800,000 years. The red area shows the average depth of the southern North Sea. So you can see that there was lots of periods during which the North Sea would have been a terrestrial landscape and then there were periods during which it became a shallow marine sea and then a kind of deeper sea. The Mesolithic period is this relatively short period compared to the rest of the quaternary. So we're sitting here right at the end or after the last ice age. What we do know is that there is a very rapid transition. Here you see a rough kind of reconstruction of what the landscape would have looked like 11,000 years ago. We have this fluvial landscapes with most of the rivers draining southwards into the English channel. Now about 8,000 years ago the entire area has been flooded. We have a shallow sea. If you look at this fluvial landscape you can imagine it's quite hard to go and try and find these mesolithic sites because it's still a very large area. So it's like looking for a needle in a haystack. So we had to go and follow the evidence and this kind of led us to this area here. As I said we started off with a regional scale trying to answer some of the geological questions and this is the footprint of the area we investigated. So this is fairly large. This is about 100 kilometers in this direction and about 50 kilometers in that direction and as a comparison that's like going from Liverpool to Leeds and from Leeds to Sheffield and trying to investigate an area from an airplane and trying to find a flint scatter. So it's enormous if you think about it in that way. So what we've done as well is we zoomed into this section here and I'll show you that now to kind of try and answer some local questions. So here again this is a zoom in here. We have part of that brown bank ridge with that scour pit to the northeast and we concentrated on two smaller areas. We have one area in UK waters, the VC45 and then we have one area in Dutch waters which is the VC40. That's still about three kilometers by four kilometers and I looked it up and that's the entire footprint of London Heathrow Airport. So it's still fairly large to go and try and find individual sites. The questions we were trying to answer here is can we actually trace a land surface and particularly can we find these peat layers that are linked to those moor logs? Can we say something more about the mesolithic landscape and what does it tell us about the Holodsee inundation? So how did we do that? We started off with doing quite a lot of geophysical surveys. We had three field seasons and during those field seasons we used a sparker source. So a sparker source is relatively low frequency. We can penetrate about 100 to 150 meters and get a resolution of about 50 centimeters. At the same time we also used a parametric echo sounder or a pest that has a higher frequency. It means we can only penetrate about 10 meters but our resolution is about 10 centimeters. The good thing is we can use these at the same time. So spark is being towed at the back of the ship and then this one the pest is being put on a pole and it can be used at the same time. So we can do a local scale deeper geology at the same time as a more local high-resolution geophysics. For people that are not familiar with geophysical data this is just to show you the difference between the sparker and the pest. So here you see a sparker line you can easily penetrate 100 meters and still see nice reflectors. But if you look at the top section then you can see that the resolution isn't it's good but it's not great. So here for example you can see this unit the kind of an acoustically transparent unit. But if we look at the same units with our pest data then we can start to see the individual layers and we see that this is a laminated sedimentary unit. So once we had our geophysical dataset we started to trace high amplitude reflectors. We started to look at certain features and we went out to ground truth bees. To ground truth we used a vibro core we had two different systems during two different field surveys and we also did some dredging. Here you can see a gillson dredge and that can actually penetrate the top few centimeters of the seabed so we can drag that along and get maybe the top 10-20 centimeters of the seabed and then we had a beam troll and that can only really pick up what's on top of the seabed itself. Once we were back in the lab we opened up our cores, described them and sampled them. We had 18 cores in total, maximum three meters length. Nine of those had petalum. We radiocarbon dated four of them and John Whitaker looked at six of them for a rapid assessment for forearms and ostracols and then Michael Grant looked at two of those for pollen analysis. And here you can kind of see what you get from those dredges and once you start to look in more detail you start to pick up bits of wood, bits of lint and even little bits of bone. I'm not going to say too much about the regional scale survey but I want to show you one line which I think is maybe of archaeological potential. So I'm going to show you one line going over the Brambank sand ridge and then over the next sand ridge to the east of it. So this is kind of what the spark of data looks like. Here we have the Brambank sand ridge, slightly deeper area and then the next sand ridge to the east of it. We have, I'll go very quickly over this, we have the older Cromerian complex sediments, then these kind of stronger reflectors, their Molagunal deposits of the Brambank formation, then we have our modern sediments. But what I want to concentrate on is the difference between the Brambank and the next sandbank along. So I'm going to just zoom into these and put them next to each other. So if we look at the Brambank you can see these clear reflectors underneath the bank, fairly horizontal. The next sandbank along is slightly different, you can still see this reflective and it stops abruptly and then it reappears on the other side and in between you can see these deeply inclined reflectors. So what has happened here is after the deposition of our older Cromerian complex sediments we had our first ice age. So the Elsterian or Anglian ice sheet came from the north and reached that area and deformed these old sediments and formed these ice pushed ridges. Later on we have our Laguna sediments kind of topping the landscape, but you can see it didn't manage to actually overtop this ice pushed ridge. So why is this important you may wonder, well if you look at some of the papers talking about the archaeological implications of the Brambank finds, then often you find the hypothesis that maybe the Brambank was a high standing area or it was already a bank, a bit like the Dogger bank, but our data does not suggest that at all. It seems to be fairly flat, similar to the rest of the Seabed in the area, but we do find the ice pushed ridges that could have formed vantage points in the landscape. It's important to still look at this regional scale geomorphology. Okay now let's have a look at these little areas, these local areas. So we'll start off with the UK area here, the VC-45. Just as a contact again, we're again looking at one of these sandbanks with this nice reflector underneath it. We kind of took a call through the side of the sandbank, I'm just going to zoom in and show you the Pest data as well. So on the Pest data you can just about see this horizontal reflector and that's where we took a call. Our call has brownish sands at the bottom, then we get a thin peat layer and then we have more kind of grayish silty sands which gradually turn into brown sands. I'm going to zoom in a little bit more so you can see even better. So here is this horizontal reflector which nicely correlates with our peat layer. We have a channel or depression feature next to it and what's also interesting is that if you get this high amplitude which we know is peat is that we also get these kind of high amplitude reflectors appearing on the side of the slope of the sandbank. So what we think is happening is that this peat land or landscape here, this layer is being eroded and that these mollock blocks are working their way down the slope. So we have in situ peat and we have ex situ peat sitting right next to it. We also did a dredge line along there. I'm going to show you some details and some more details for call. So here you can see some of the bits of peats that were dredged up as well as some flint and pieces of wood. So let's look at the core a little bit more detail. So I'm going from bottom to top. The bottom is this kind of grayish brown sand. OZL dates are coming back at about 12 to 13,000 years ago. Then we have the development of our peat starting around 10,600 kbp and stopping around 10,200 kbp. And then we get into our silty sands above that and then our marine sands. Now interestingly there are no forearms and no ostracoths in this lower sandy unit and then they start to appear above our peat layer but there's not many of them. So how do we interpret this? We start with fluvial landscape in the transition between the late white sand into the early whole sea. Then we have our trestral peat surface developing during the early whole sea. Then we have an intertidal phase during the early whole sea before we get our full marine inundation. So what Meru has done is she has mapped this peat surface, that's the red here, and then you can see this blue is where that channel is cutting through that peat surface. Now on our backscatter data we actually see very little but if you look at the backscatter, you can just about see this thin darker line here and that's where the peat layer is being exposed on the side of our sandback. So that's our peat outprop. That kind of gives you a little bit of a reconstruction of what that looks like. So we have our green sandbank and on the side of it we start to see the peat layer coming out and kind of falling onto this slope of the sandbank. And I'm sure many of the archaeologists are very excited when they see that because it is a bit reminiscent of what we see in Bordeaux Cliff. So this is definitely an area you want to go back to and analyze in more detail. So now let's have a look and go to our more eastern side in Dutch waters and I'll just quickly show you the kind of the similarities between our previous site but also some differences. Just to put it back into context, so this site is located between the brown bank and that ice push bridge I showed you earlier. So we were targeting this high amplitude reflector here and some of the features that we could see when we zoomed in. So for example here we see this depression is about a meter deep and we took a core straight through that and we also had a dredge line. Again we have brownish gray sands, a thin peat layer and then these more or less laminated silts and sands and clays and then a fairly clear surface or transition into these brownish sands. I'll show you some more details again. So we start off at the bottom with these brown sands. Our OASL data are coming back around 11,000 years ago. We don't have a data at the bottom of the peat but the top gives us the radiocarbon data for around 10,200 Kbp and then we sit into these laminated sands. We see what looks like an erosional surface than these brown sands. Again the bottom sands have no forearms and no ostracods in them. It's completely barren and then above the peat layer we start to see these brackish ostracods and forearms appearing. So it's fairly similar to what we saw in our previous site in that we start with a fluvial landscape in the transition between the late white salient and the early Holocene. Then we go to a more terrestrial peat surface and we go into an intertidal environment with a tidal river and possibly brackish mud flats before we have a fully marine transition. I'm going to show only one more core and the reason I'm showing you this one is to just demonstrate the point that we can't just link or correlate all these units across a larger area because you'll see here we have a slightly different story. So this was the core I just showed you we're going to go just a kilometer and a half maybe two kilometers further to the north and this time we have a nicely cut channel here about five meters deep. We initially targeted this reflector right at the top but now we're not actually quite that sure that we are seeing this reflector in our course or whether maybe we managed to core a little bit deeper because what's our core showing again we have sands at the bottom that a nicely developed peat layer and then again these laminated sands and silts and clays and we have a clear erosional surface and a bit of a messy layer right on the top. So let's have a look at what we are seeing here this time we also have some pollen data so it's nice to add on for a parallel environmental point of view. So we start from the bottom we have our sands which again have no forehands in them and no ostracods but we have freshwater percolar and some fish remains. The pollen are showing that definitely at the bottom there is a domination of pine in the landscape with some heathland and as we start to go up the sequence we start to see the appearance of river marsh species. The peat starts developing around 11,000 calvapie and stops developing around 10,200 calvapie. The pollen is showing that in the same way as Ben was showing in his presentation that we start to see an increase in hazel as we start to move up towards the peat but interesting there are some coastal species so the coastline is probably not too far off. Then the transition between the peat and the overlying unit is conformable so we don't see an erosional surface there's no hiatus. We thought that here we were going to be going back into this intertidal settings but we're not again there are only freshwater ostracods no forehands and freshwater snail or percolar. And the pollen interesting us showing us that we're starting to move towards more grassland. So what we have here is at the bottom we have a fluvy landscape and the pollen seems to suggest that we're looking at a slow flowing environment so fresh water but slow flowing so something like an oxbow or a cutoff channel. Then we have the development of a damp fen woodland but the coast is not too far off there's potentially a dune setting nearby. Then we have another unit that shows us a fluvial environment where there's a continued presence of water pools and marshes before we get our marine inundation. We don't really know where the intertidal sediments have gone but they seem to have been eroded. So what Rachel has done is she has potted the bottom of these strong reflectors here and created the surface from that and that's the surface what you see here. We're going from south to north in the southern area we have these shallow depressions as we can see here about one meter deep and as we go to the north we start to get proper channel cuts so you can kind of see these bluish areas here. So what Rachel has managed to do is kind of join the dots and then come up with this reconstruction of this potentially meandering river system which has different phases and that kind of fits for what we see in the pollen is that we possibly have oxbow or channels that have been cut off. Then further to the south we seem to have more either abraded river system or smaller streams or maybe depressions and pumps. Okay so what have we done so far so on the local scale we've managed to detect that peat surface. We've started to characterize the mesolithic landscape and the last thing I quickly want to show you is what we started to look at is this inundation, this holistic inundation. I'm not going to go through all the dates one by one but just to show you roughly where the kind of the geographical dispersion is of these dates. Interestingly our oldest deepest peat is only about a kilometer away of our youngest shallow speets so what I'm going to finish off with is plotting our peat dates against depth and what the colored lines here are that's model outputs that I got from Sarah Brogd Bradley based on GIA modelling and these here is our oldest peat at the bottom and then we have our youngest peat at the top. I'm just going to plot our highly environmental data next to it so before we have our peat we have our fluvial landscape which is pine dominated. Then we have our damp peatland with deciduous woodland nearby and slow water. Then we have our estuarine tidal flats and creeks and then finally we have our coastal inundation. We have to point out that our peats are limiting points there is no evidence of salt launch anywhere in any of our pools. So when I look at this then to me it seems like this green reconstruction fits our data the best in that that is a terrestrial surface sitting a little bit above where the sea level was at that point. Okay so has our strategy paid off? We started off with big picture questions we got more data resolution got better but at the same time the complexity increased and now we probably have more questions than we had before. On the big picture it's interesting to see that those ice pushed ridges formed a really important feature in the landscape and we can't forget these regional scale features. We do need to maybe have another think about the influence of that deeper channel that's cutting the whole area. It's a very big deep channel and it must have influenced the landscape, it must have influenced the hydrology and also must have been an import migration pathway for people living in that landscape at that time. So maybe we need to think a little bit again where we need to try and find for missile sites rather than concentrating just on that brown bank sandwich and landscape modelling is going to be very important for that. On the local scale we managed to trace map and target land surfaces. We now have more sea level limiting points which are older than what we had before and we have environmental information that we can add on. We don't quite understand the fluvial landscape quite yet. We don't quite understand the variation across the landscape yet so we need to try and understand that to understand how sea level changed over time. What we also now have been able to address yet and that's definitely the next step is how or where would people have lived in that landscape, how fast would they have had to adapt to the inundation and what has realistically been preserved. So the future. Our answer is always more data but I've put a little question mark next to it because we have a lot of data already. It's now just a question of rethinking or thinking again about the questions we want to answer. Where do we need to go and find the data? Where do we need to collect more data and what kind of data do we actually need to answer our questions? So we need to also make sure that we keep a good trade-off between answering the archaeological questions and the geological questions. In any case we're going back in June with a reduced crew of four scientific people so we can only do some seismic acquisition for 24 hours. We're going back as I said in June on the Seaman Steven and then we also have some time on the Belhika but the Belhika is not quite a service yet so it's either going to be the end of this year or start of next year. But I'm hoping that this talk may spark some suggestions or discussions on where we should go next or where our priority should lie next. I'm sure everybody's starting to fade at this point. It's a very long day so if you have any questions, remarks or suggestions either put them in the chat or just send me an email and I'll try to answer them as well as I can. And that's me. Thank you Ruth. That was an excellent talk. Okay we're back to the other time which is great. Wow people have gathered themselves again. We have a question of Robin Edwards here. Thanks for a great talk Ruth. Do you think there are any locations where salt marsh sediments will be preserved or were they all eroded during inundation? Yeah well the interesting thing here is that I'm not sure that where we have been looking that they've been eroded because we seem to have a conformable transition between our intertidal and our peat layers so it seems like where we're looking is that it's never really formed. So maybe we'll have to look further west or kind of southwest and try to find where that coastline actually was to find where the salt marsh would have had enough time to form above the terrestrial peat surface but at the moment that there is no evidence for salt marsh where we're looking. Okay another question here of David Field. Are you able to say where the parts of the bank were above water at the beginning of the Neolithic say around 6000 BP? If not can you account for the Neolithic access ritual deposition on a remembered landscape artifacts from a capped size boat? That's a good question. It's a very good question because that those polished axes are a real conundrum. It seems like the area would have been completely inundated by about 8000 Kp so and it was not an upstanding feature as I showed there was it was just fairly flat and then kind of those sand ridges formed towards the Holocene the south of the Holocene. So it must have been deposited there by someone who came there by boat that's the only way I can think about it and our data doesn't seem to suggest anything else and what has already been suggested in the literature about that. That's a good very good question. Any more? Anthony Firth, is the survivor of these deposits an accident of the presence of the bank features of marine sands or did marine sands form over topographic highs in the underlying surface? Yeah to me it looks like the marine sands formed but not over necessarily topographic high in the underlying surface. That's kind of what our regional data is showing us at the moment but we may have to look at the more local higher resolution data to actually confirm that whether it's an accident that they're preserved or whether some more effect that fishermen are trawling there and it's just an accident that we have a lot of material coming up because people are actually fishing and trawling there and it's an artifact of that. That's another question I think that needs to be answered and also the fact that the peat layer is starting to erode out of those banks is probably a reason why we start to see these artifacts coming out. Why they're being eroded now? That's another question so it might be worth having some kind of oceanographic modelling to see why these peat layers are being eroded at that moment or they're being eroded now but the peat layer where we see the peat coming out that's a really important site for us because it's there at the surface and we also know it's still there in situ so it's the perfect place to go and find artifacts as they are preserved in the peat. Just to kind of comment for myself really your point about rapidity of change in the radiocarbon data, it'd be interesting to see I don't know whether any of those have been modelled so there's kind of rates of change. It'd be interesting to maybe look at that in the context as some of the data from lost frontiers more broadly to look at some of these questions of rapidity and relative rapidity and so forth. That's just a kind of thought I had on when I was hearing you talk then. I think it'll be interesting to kind of join the two sets of data now and see how that landscape has evolved. We see similarities but we also see differences and it'll be nice to tease that apart. Yeah I mean it's like sometimes with these submerged landscapes we tend to think of it because we can't see them almost as being all similar process operating across the surface which obviously isn't the case on dryland, it shouldn't be the case with a landscape under the sea. Anyway how are we doing? Any more questions? We've got a couple more minutes if there's any more for any more or if not I'll just pause briefly there.