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0:03
Jane Harrison: Okay, can everyone hear me yep okay good right so last time we talked about the before and after of an excavation and this week. Jane Harrison: I want to discuss everything that happens on site and and why that happens and, of course, you all know, there's a lot more that happens on site then just charging and finding things. Jane Harrison: And I can't cover everything in detail in just an hour and a little bit and, but I want to start looking at how a site is and picked.
0:38
Jane Harrison: discuss the idea of a context and the critical and the critical significance of the relationships between elements of a site, so the less the structures and all the other things that make up a site and the importance of detail and cross checking.
0:58
Jane Harrison: So we always remember that that it's a responsibility we're taking a site apart and our records and the quality of your digging. Jane Harrison: doesn't just allow people working in post excavation after the excavation and to be able to end envisage the site, as you found it, but also to really understand and interpret it and and try and.
1:25
Jane Harrison: get to the bottom of it story, so the excavation process is actually more than that phrase preservation by record it's more than just capturing a site in writing and drawings and photographs. Jane Harrison: And, as a consequence, what happens on site is fascinating and challenging and the recording methods that we use are designed to be detailed and comprehensive.
1:52
Jane Harrison: and have built in fail safes but they're also intended to make you think when you're working on a site so, for example on the slide you can see a field drawing here.
2:08
Jane Harrison: Which is a section from the war town crags X excavation through phases of war collapse and and.
2:19
Jane Harrison: it's it's a detailed scale record of what that section looked like the stones and the soil is in that section. Jane Harrison: But it's also an interpretation of what happened and that's a really important thing about site drawing. Jane Harrison: and on sites you'll do both plans, which are the bird's eye view and these vertical sections, so they can see. Jane Harrison: Section going into way or tan crags and planning and away on a site of mine in Oxfordshire.
2:50
Jane Harrison: And then, of course, there are lots of other things that that happened on site like collecting samples and we'll come back to those. Jane Harrison: And I think, even if you're not planning to actually be on site and take part in any of the excavation and the things that happen on site.
3:08
Jane Harrison: If you're interested in archaeology you do need to understand how evidence has been gathered in order to be able to evaluate the stories and narratives and ideas that people generate off the back of that evidence so that's part of what i'm trying to to do tonight as well.
3:28
Jane Harrison: Okay, so we'll be thinking about, amongst other things, what actually happens on site, what are the approaches to digging up a site, how do you go about exploring the various features on the site.
3:43
Jane Harrison: And what are the stages of the digging process why archaeological stratigraphy is central to that digging to the practice excavation and how we record sites and you can see that, on the slide I sort of typical classic open area research excavation where you've got quite a big.
4:05
Jane Harrison: area of land open and then on the right, you can see, almost the extreme opposite, which is a watching brief at peel gap. Jane Harrison: And that's where we're repairing the dismantling and then repairing a collapse on the wall, but an archaeologist is there to make sure that anything significant is recorded and now you can see.
4:28
Jane Harrison: Some some original and non clayton Roman fabric that slipped out of place as part of the collapse.
4:39
Jane Harrison: Okay, an excavation is an exercise in project management and. Jane Harrison: From what we talked about in the last session we've got to the point before the excavation where everything is in place we've done our background research we've got our research questions we've got our permissions. Jane Harrison: And we're actually physically setting it up, and of course there's a huge variety of physical infrastructure that goes with an excavation and.
5:06
Jane Harrison: You can see on the slide now, this is the infrastructure for a fairly big open area excavate excavation as part of a community rooted project and in a suburban area and very neglected Patrick can you can see that there are toilets, and I sort of place to keep.
5:27
Jane Harrison: paperwork and drawings there's a little kitchen somewhere to shelter somewhere for the equipment. Jane Harrison: And in order before we got to that stage would have had to clear the ground and open the trenches and put up fencing and tracking. Jane Harrison: And in this case, this may look very similar to what corporates like we have to have a sump pump going over the full period of the excavation to keep that one open.
5:55
Jane Harrison: But then, of course, you don't have so much infrastructure if you're doing something like wartime crags there we had plastic bags and.
6:04
Jane Harrison: cheating to keep stuff dry we had.
6:08
Jane Harrison: Again sort of minimal fencing to to protect the area where we were working on and we had our tools in in boxes, and that was pretty much it and oops sorry. Jane Harrison: And then on the right, you can see how we got to work doing an excavation on an uninhabited island that's the geophysics crew and piling into a rib to go across to the island and there are there.
6:33
Jane Harrison: The infrastructure was a tent to protect the geophysics equipment and that was it so all sorts of things can be covered.
6:43
Jane Harrison: And then, when you come on to onto the site, there are certain key elements that in a sense, will always be there, whatever the excavation. Jane Harrison: Whatever the size or location of the excavation and there'll be some form of shelter for valuable and more rain sensitive things whether it's a big plastic box or in this case, a little site office just off the the the picture here.
7:07
Jane Harrison: And there'll be some sort of shelter, most of the time for the workers, although not always. Jane Harrison: And they'll be perhaps an equipment store and toilets in it for this excavation we had an arrangement with. Jane Harrison: The local council and there was a really nice set of toilet box associated with it a bit just near to the coast. Jane Harrison: And with a beach and we pay them a little fee, and we were allowed to to use that and very nice and clean, it was.
7:37
Jane Harrison: And you might need fencing and then, of course, there are the trenches and, very importantly, the spoil heaps This is one thing you do have to think of in advance, where is all the stuff you dig out going to end up.
7:52
Jane Harrison: In the case of this excavation where it was very Sunday and windy we had to think carefully about the prevailing winds, because we didn't want to be constantly downwind of a sudden spoil heap and you can see we've used the turf to create a little shelter for people and things as well.
8:11
Jane Harrison: So that's the the elements of a site.
8:15
Jane Harrison: Now.
8:17
Jane Harrison: The overall process is that you are trying to excavate in reverse order to that, in which the site, the layers of the site were created. Jane Harrison: collecting, recording and considering the evidence as you go along to try and generate the best possible understanding of what happened in the past to create.
8:39
Jane Harrison: What you are dismantling and i'm going to now look at a range of approaches to actually taking attention to an area apart to digging and there are a lot of strategies also have ways of approaching a site once you've got it uncovered.
8:58
Jane Harrison: And all excavations as well as recording the details of any structures of.
9:05
Jane Harrison: Any ditches or pits and last, and all the things they defines that come up it's really important that you're gathering horizontal and vertical information on the relationships between. Jane Harrison: All those elements, the last the pits the deposits, the features, the bits of structures, because that is the essential framework for all the other information, the finds.
9:34
Jane Harrison: The dating the samples your mission record you're drawn record if photographs so it's really important. Jane Harrison: And I think when you're digging to have that in always in the back of your mind How does that relate to you know how do these elements of time looking at relates to one another, is is really important.
9:54
Jane Harrison: And then, when you tackle aside and more smaller areas narrower areas deeper excavation is often a really good way of collecting vertical relationships, whereas a bigger open area gathers horizontal information.
10:14
Jane Harrison: But what is often the case on archaeological sites is they are what is known as truncated, which means that, over time, whether it's plowing or. Jane Harrison: Later activity has taken off the top of the site. Jane Harrison: So what you're getting is not the full depth of the original archaeological layers and deposits, but you're getting you've lost I don't know, maybe 30 centimeters or whatever it is.
10:44
Jane Harrison: To the plow and otter stripping topsoil for potatoes or to building whatever it is, and you can see, on the slide here. Jane Harrison: This is an iron age site with a huge number of interconnecting pits, some of which had been used in their final finally for burials. Jane Harrison: But it is quite truncated we've lost nearly half a meter of the tops of those pits so that working out how they related to one another.
11:16
Jane Harrison: was really difficult because you've lost the horizontal surface on which relationships can be established, and so it was where. Jane Harrison: The pits intercut so well one pitch have been used and filled up and another had been cutting and taking some of that pit away That was where we could get relationships, but the horizontal ones were. Jane Harrison: Otherwise, and missing because of in this case a combination of cloud damage and topsoil stripping.
11:48
Jane Harrison: But all the approaches i'm going to talk about are often compromises and between gathering vertical and horizontal information. Jane Harrison: and almost all larger excavations use a combination of approaches, according to the specific demands of the archaeology you're dealing with and. Jane Harrison: being flexible about your approach is key to excavating a site well and, indeed, most of the techniques i'm going to cover briefly in the next few slides are all used within.
12:20
Jane Harrison: area excavation.
12:24
Jane Harrison: Okay, so i'll just use this site as an example of how you combine horizontal and vertical approaches, and this is an early Anglo Saxon hall and. Jane Harrison: These are the foundation trenches for the post date the plank in in trench construction of the call it's really difficult to see even in this lovely aerial shot it's quite hard to see whether the trenches for the walls of the building are, and that was partly because.
13:04
Jane Harrison: There is heavy truncation again we've lost the top nearly half meter of that site, but also because there's a rising and falling water table.
13:15
Jane Harrison: In this particular spot, which has taken all the organic material out of the out of the trenches so that they are very similar now to the surrounding undisturbed sub soils, so what we did, if you look at the slide you can see that we have.
13:34
Jane Harrison: Clean down quite a little bit and then we've taken it deeper over the wall trenches in order to get this clear picture is, we can have the plan of the building. Jane Harrison: And then we've gone down deep in these boxes, to look at the profile of the war trenches because it was almost impossible to just dig out the feel of the ditches because of this complication of rising and falling water table, and what that had done.
14:03
Jane Harrison: To the the archaeology So you can see here that's looking across that site, and this is what you can see, in the section in the vertical profile of one of those boxes and you can see here's the the outline of the.
14:22
Jane Harrison: Of the trench for the planks and that made the built the building the bottom is very unclear, because all the shifting of water and i'm salts has has has has.
14:35
Jane Harrison: Has merged material at the bottom and the material in has actually bellied as well and obscured the side to little bit So you can see, there were having to combine approaches.
14:49
Jane Harrison: Right so.
14:53
Jane Harrison: The creation of an archaeological site with during its use and after the its abandonment is complex, because it shaped by the existing landscape, the geology the solid and drift geology. Jane Harrison: By the light of the land, the topography and the hydrology the water courses then also natural processes have an effect erosion.
15:18
Jane Harrison: alleviation, so the depositing of silt Columbia, which is the movement of material Dan slope and other ways in which. Jane Harrison: sediments moved around by wind and water and worms and and other borrowing animals or via automation as we call it, and all those things can both add and remove less and there's a very. Jane Harrison: good example of that when we were digging in that windblown sons in Orkney and other places.
15:49
Jane Harrison: Where the sand and you see in a storm is lifted off some areas and then deposited in others, and that was a sort of quick time. Jane Harrison: example of what happened over a longer period on sites and so material can be added and taken away and less can be changed after they've been deposited. Jane Harrison: By some of those natural processes, and those are called post deposition or processes, so the things that happened to the site.
16:18
Jane Harrison: After it's been buried and abandoned and worms roots borrows chemical reactions and precipitation, for example, I insults rusting and plain old decomposition can all have an effect on what the site out on the site and then of course people.
16:36
Jane Harrison: Both while it's being used and after it's been abandoned people change archaeological sites and they remove parts of archaeological sites so i'm picking this. Jane Harrison: is really complex and now what's called strata graphic exploration is the method we all use to help us think about what happened and to try and understand it, as well as possible.
17:01
Jane Harrison: And so that's excavating all the contexts and i'll come back to that in reverse order now stratigraphy in the archaeological sense is a sequence of contexts and contexts, are they represent an action, so a layer might be a buildup of rubbish deposits.
17:27
Jane Harrison: A deposit might be a very clear.
17:31
Jane Harrison: dump of say metalworking material within that the phil is what gets put in a pit or a ditch or a post hole and a cut is an interesting one, because it's an action. Jane Harrison: you're removing material from this from the ground to create a post hole or a ditch it doesn't have a physical presence, but it has a shape. Jane Harrison: So what we're trying to do is to record all those contexts and to understand how they have formed and the excavator is someone who is.
18:09
Jane Harrison: dissecting those context recording them and trying to understand how they're formed so it's manual it's thera but it's very thoughtful it's what some archaeologists call interpretation at the child point. Jane Harrison: you're digging you're retrieving you're recording and you're reflecting and and there's a there's a sort of sequence, which you go through in a time and time again as an excavator on site.
18:40
Jane Harrison: An area is opened and clean, so we can have a best look at what might be there it's photographed and drawn. Jane Harrison: And then, as an individual you'll get a context you'll get a unit of that archaeological to Timothy to deal with, maybe it's a pit that you've got to excavate. Jane Harrison: And you will get a number for the first fill of that pit a unique number, that is, the label for that particular unit is to to graffiti or context it's all it is it's a label.
19:12
Jane Harrison: And you have to photo it before you start digging draw it before you start digging and then start describing it on the written record and we'll come back to that. Jane Harrison: And as you excavate you should be continuing to think perhaps to make notes and to record things.
19:28
Jane Harrison: you'll be putting your bulk finds in a tray with that unique number for that particular thing that you're excavating with the tray and i'll come back to those you might be collecting samples and and you might be finding small finds again, which I will come back to, and if you are.
19:49
Jane Harrison: digging a pitch you might have to draw half of the half section of it and we'll come back to that at the end, you have to finish your written record. Jane Harrison: You have to take a formal photograph you have to make sure it looks it looks absolutely beautiful to photograph it and you have to do a post excavation, then you double check everything and you start again so that's the kind of process and sequence, it has a kind of rhythm to it.
20:18
Jane Harrison: Okay So here we are, with some more area excavation and and.
20:27
Jane Harrison: As I said, this is this is good for both horizontal and for both horizontal and complex relationships and indeed for picking up complete structures, like we saw with that early Anglo Saxon hall.
20:40
Jane Harrison: And it's almost invariably used, along with that more contained narrow excavation to create the vertical sections as well. Jane Harrison: And and those can be sections that are in slots to to dig that can be the trench side and i'll talk a little bit more of more of them more about them and in a moment, and before I expand the slide, let me just refer you to one one master excavator Martin Carver who.
21:11
Jane Harrison: obsessed about keeping sites clean and tidy I think you'll find that most archaeologists however untidy we might be in our private lives are very clean and meticulous on site. Jane Harrison: Because it is true that the more tidy your site is the least the less loose soil is about the straight to your edges are when you're when you're cutting down into sections.
21:38
Jane Harrison: The better chance you have of understanding and so you can see, Martin carb are getting really carried away if any proper research is intended, there is no substitute for keeping everything permanently and ridiculously clean so you've been warned.
21:56
Jane Harrison: And so it's tools trenches records everything, but he also said tidiness comes before talk there, I disagree with him, I think, talking. Jane Harrison: sharing experience swapping notes looking at other people's work and talk in and discussing it is really, really important when you're on site okay so here, you can see more area excavations where you've got pieces of buildings, this is part of a primary.
22:24
Jane Harrison: there's actually here and a little moat and we've cut sections across it in order to look at the profile of the moat within the open area excavation and here you've got.
22:38
Jane Harrison: That on each site again where we've cleared the whole thing, but then we cut taking half of the pits out and in the order in which. Jane Harrison: They you know, in the reverse of the order in which they've been intercut so we're combining vertical and horizontal and here you see again in an area excavation a deep section through a very deep mitten. Jane Harrison: In ot me and so again a combination of open area horizontal and deeper digging in order to look at vertical sections.
23:16
Jane Harrison: Okay, and so, sometimes excavations run over several seasons, especially research and Community ones and and here you're quite often thinking about maintaining.
23:29
Jane Harrison: A strategic section, so an important vertical.
23:36
Jane Harrison: Section across an area, this is a Viking longhouse we're looking at two thirds of it here the was running around. Jane Harrison: This is the entrance paved paved entrance passage way here's the entrance into this, which is the domestic end of the longhouse, this is the cooking and there would have been wooden.
23:56
Jane Harrison: platforms here and and benches along here, and these are the remains of hearts that have been built in in the Center of the longhouse and we have dug down by this point well over two meters, but as we went down, you can see here.
24:16
Jane Harrison: We would add that little.
24:20
Jane Harrison: That little book that little line running across at the Center of the longhouse and as we go down, we were actually recording drawing each. Jane Harrison: Section as we go down, but then because it's it's in the sand and it's quite vulnerable.
24:35
Jane Harrison: we're taking it down but we're adding on each time we're adding on another bit of the drawing so that's called a running section, where you record it and take it down then record the next bit and take it down again so you can combine it with an open area excavation.
24:51
Jane Harrison: And here's a kind of a much more contained example of a very targeted trench. Jane Harrison: And where we're looking, this is obviously this is, this is a really interesting vertical section of the wall and but in order to get a section looking at all these phases of. Jane Harrison: collapse we've gone down in what's often called a son dodge, which is a deep and small look see down into the archaeology.
25:20
Jane Harrison: And here's another another little sundance in the corner about a trench where it's really looking to see. Jane Harrison: How deep the deposits are, and this is reached, the the understands sandy subsoil here and gives us a. Jane Harrison: sort of handle on that sort of depth that you're dealing with not be really helpful when you're planning how much you can actually get done in a season.
25:41
Jane Harrison: And, and here is one of those pits half section those aren't age pits, and this is actually to into cutting pits, and this is the latest one of the pair. Jane Harrison: And so that's been dug out first and we've taken out half of it, so you can still see the shape of the pit here. Jane Harrison: it's plan we've also got a really nice look at its fills and then you can see that there's there's something different here than there is in this part of it, and if you look here.
26:15
Jane Harrison: This is the fill of the earlier pit and that part of it has been cut out by the later pit so you're catching a relationship as well, and this was the running section that I was talking about through the biking longhouse.
26:31
Jane Harrison: Other approaches.
26:34
Jane Harrison: If you've got a big sort of heterogeneous feature like a mitten which can be really, really hard to disentangle you know thrown bucket load of slops by. Jane Harrison: Throwing bucket load of fish fish scales, or whoever it is and and so to some poets character and to get some sections, through it, some looks. Jane Harrison: Vertical looks at it, you can do this kind of thing where you're you're not digging the whole thing but you're sampling from the whole area.
27:02
Jane Harrison: of what is in it, and what you're getting from it and for analysis we're also getting all these little sections through it and, and this is a sort of similar approach, this is a bronze age.
27:16
Jane Harrison: mound and in the old days with anything that might be in a burial Mounds the What happened was you went into the Center and you just stepped down looking for whatever might be buried in the Center now we use most usually do something called quadrants and take out a quarter.
27:35
Jane Harrison: And then you've got these vertical sections through it and you've got the plan of what the what the man's looks like and this one they've actually established, you can see a grid.
27:48
Jane Harrison: Over the mound and that they will have been using that to assign fines and samples to a much more contained area within. Jane Harrison: One big context, this big stony context so they've got some idea of parts of the mound from which finds might come. Jane Harrison: And here, you can see a similar approach to a really big huge big pitch, which has had one quadrant taken out already and they've started on a second one.
28:16
Jane Harrison: And what that will do again it'll give you the fines from inside half of the pits he'll give you the shape of it if we give you a look at the phils but also by doing two quarters like that you'll get a section right through the Center obviously as well.
28:32
Jane Harrison: And then, this approach on that uninhabited islands, the.
28:37
Jane Harrison: eroded by King structure is called tapestry excavation and it's where you're excavating vertically, instead of working across horizontally you're actually taking em shaving downwards and taking a bit off the front in order to record a section.
28:55
Jane Harrison: Okay, and finally there was that.
28:59
Jane Harrison: The program about test putting in people's back gardens, this is a test fit in the back garden and away. Jane Harrison: In another project and it's a way test it's a brilliant because they're fabulous way sometimes you find extraordinary things that they're aware of sampling what's going on, you get the pottery. Jane Harrison: And you get other finds you got to look at the deposits and if you have enough of them scattered around an area, you get a really good sense of.
29:27
Jane Harrison: what's going on in particularly villages or suburban areas and these long thin trenches that commercial excavation. Jane Harrison: Commercial escalations do coke evaluation trenches are ones that are literally about just seeing what the survival of the archaeology is like before suggesting what happens next, and here you can see narrow.
29:51
Jane Harrison: slots within larger excavations us to explore again depth and vertical relationships.
30:00
Jane Harrison: And finally, here, you can see a very complicated on each site with a number of drainage ditches and ditches for enclosures can see on this very difficult to understand plan and again that was one where because you've got very hard to distinguish.
30:19
Jane Harrison: As it's very hard to distinguish the sub soils into which ditches and pits and post tells a cut from their phil's you're working with both area excavation and doing these.
30:34
Jane Harrison: box box sections where instead of just digging out the full of the ditch you're digging over digging it so you can see the profile.
30:43
Jane Harrison: as clearly as possible, you can just about see the profile of one of the ditches there and just take note of this, this is one of those wonderful iron age storage pits and we're going to come back to this so just have a look at how it looks.
30:57
Jane Harrison: and imagine trying to photograph that.
31:02
Jane Harrison: Okay, so all those different approaches to how you take a site, as I say, are ones that you're likely to use in combination. Jane Harrison: And it's very difficult to predict ahead of time what you're going to do exactly because you don't know what the archaeology is going to be like but you'd have all you're always thinking.
31:20
Jane Harrison: Okay, how am I going to approach that how am I going to pick and understand that and, of course, it's very important to know exactly where things are within the trench. Jane Harrison: And location is very, very important, and sometimes the details. Jane Harrison: don't know these can escape and it's actually surprisingly easy to lose the precise location of pits if you're not careful about how you're recording things.
31:47
Jane Harrison: So sometimes all the recording location or recording is done by a total station, so no electronic instruments or by a survey great GPS, or sometimes. Jane Harrison: Each of the open trenches will have its own mini equivalent of the ordinance survey national grid setup but it won't be with the big long numbers, we use in Ordnance Survey, it will be. Jane Harrison: Using nice straightforward numbers, but then the system works exactly the same as reading a map reference.
32:19
Jane Harrison: So you have an arbitrarily established point outside of your trench there's a 00 somewhere and off the slide and all the site good measurements are taken from that point. Jane Harrison: And he can see here's the trench side it's grid, and it will have a selection of little pegs along the side of the trench marking, where the grid points are and you're then able to measure where everything within the trench is so if you've got a gold coin, you find here.
32:55
Jane Harrison: You can locate it because it said 14 meters East you always do the eastern the easterlies first, just like in an audience survey readings and.
33:06
Jane Harrison: 18 meters North and so immediately, you know sorry, you know where that is but the point of this slide really is just say just remember that location is really important.
33:18
Jane Harrison: Now let's go back to the physical things that you're extracting and keeping from a site here we've got what are known as.
33:31
Jane Harrison: Bulk fines and they are the things that you find within that layer the context the soil that you're digging the pit post hole the ditch.
33:43
Jane Harrison: That are collected, without any more precise spatial data so they're not located precisely within the area that you're digging and that can include, as you can see in this tray bone and pottery.
34:01
Jane Harrison: tile or what's known as ceramic building material is the capital, in this case the nuns of the primary that we were excavating there were using a lot of oysters. Jane Harrison: And, and you can see that there's a little tag on with the tray which gives the trench number, it gives the context numbers at the number that labels your soil.
34:24
Jane Harrison: and
34:26
Jane Harrison: Sometimes a metal artifacts metal bits are part about phones on other sites they might be special more special fines and i'll talk about small fines in a minute, and on the right. Jane Harrison: You can see the front page of a filled in written record sheet for context, and you can see, this a lot of information on there now talk a little bit more about those but i'm not going to have time tonight to talk about the detail and and that's something I hope we're able to do.
34:57
Jane Harrison: trench side talks on, but you can see, on this form at the bottom here, it says Och fines. Jane Harrison: And it gives a detail of the findings that were that were collected it's not actually the this this tray and the sort of proportion of fines, there are, in the context and the sort of condition that they're in.
35:19
Jane Harrison: And here is a small fine now small finds can be huge and they can be a cornerstone, they can be a tiny little bronze age Tang barbs and tank data head, like this one. Jane Harrison: But the point about them is they're particularly diagnostic there, particularly helpful in some way they're particularly valuable or particularly unusual.
35:42
Jane Harrison: silver and gold artifacts evidence for metalworking coins either metal artifacts worked bone worked stonework flint and, for example, you might. Jane Harrison: record all the hub nails you find on a Roman site, although I have to say that you can regret that, because when. Jane Harrison: When you're recording every hop now there's a small find and it's a very rich sites that can get a bit out of hand, so you have to think a bit about what you're recording in this way because.
36:11
Jane Harrison: These small phones these special diagnostic times have a whole separate numbering system their own number. Jane Harrison: which goes down here in a triangle and they have their own separate recording system and adult within a slightly different way, because you have to locate them precisely in space, so not just with their site grid reference, but also with their height above sea level.
36:39
Jane Harrison: So you also take environmental samples and as you're taking, you can see, at the digger here has got those big white buckets and she is collecting. Jane Harrison: A general environmental sample to be taken away to. Jane Harrison: We talked about the post decks where these big saw samples are taken and put through a system of saves with running water.
37:03
Jane Harrison: To get charged grain and seed and tiny little bones and other very small environmental bits of data, out of the soil and you just literally put. Jane Harrison: All the soil, without taking things out into the bucket and that's taken away to be analyzed but, of course, you need to record that you've done that fact.
37:24
Jane Harrison: So there's a place for you to give it to record that you've done it, it has a separate recording system there's more paperwork and another number that goes in a diamond you might take smaller soil samples like these ones are separate analysis and they're recorded down here.
37:44
Jane Harrison: And there will be different sampling strategies on every site.
37:51
Jane Harrison: Okay, and then there's also the written record and i'll talk about a contact sheet in a moment, but there's also. Jane Harrison: Quite often, the supervisor or the director there an excavation will keep a running notebook recording their decisions and thoughts and actions. Jane Harrison: And, quite a few diggers, will do that too, as well as the former record and those can be immensely helpful and because they chart the changes in your ideas and thoughts about the site.
38:21
Jane Harrison: And there's also the photographic records and and there's a whole range of different photographs that get taken on site and they work together with the drawn record, so you get things, called working shots this is definitely a pre covered site that's beginning to clean up a new trench.
38:42
Jane Harrison: This is a pre excavation shot, so you can see that there's some sort of ditch here and the end of a ditch here and the edge of a pit here. Jane Harrison: But they haven't they been exposed and shown below the the plow soil, but they haven't been excavated and that's a formal shot with a scale and an ortho and here's an aerial shot.
39:07
Jane Harrison: At the same area after excavation it's on slightly different orientation, but they stitch here. Jane Harrison: has had some slots motocross it the pit has been excavated half section there's the vertical section that little ditch and has been explored, as have these loopholes and that's a post excavation shot and that's done with a boom.
39:30
Jane Harrison: And then you also I like to do ended a shot, so you do a quick shot run and walk around the trench and take where record shops shops, of what it looks like at the end of each day because again that helps Pope chart our progress.
39:45
Jane Harrison: And then there's the the core of the written record, which is the context sheet, so this is the sheet and that records all the details about that unit of strategic griffey. Jane Harrison: That layer that's rubbish lead that metal working deposit that cut for a post all that filler the pit which represents an action in the past, this is where all the details about that.
40:15
Jane Harrison: context go and and there are all sorts of basic information that go at the top of the sheet and there are, as the the records of the fines and the small fines and the sampling and here in the middle and you've got prompts to help you describe.
40:36
Jane Harrison: The the soils according to a sort of formula, but there's also a space for describing it and.
40:45
Jane Harrison: What it what it looks like in relation to other things and give us the overall description and also for you to try and and suggest what might have happened in the past, and in order to produce the thing that you're describing and so it's.
41:04
Jane Harrison: it's it's about location and description and a measurements and comparison and comments.
41:11
Jane Harrison: And it's it's absolutely vital part of being on site and then the back, is for doing the drawing and putting any more.
41:21
Jane Harrison: Information you want and drawings are really helpful because they can be annotated and he can see another filled in one with all the details there and a little sketch on the back. Jane Harrison: of where the the context actually is, and you can see, here it is and and here it's in relation to other deposits here, this is a wall and and.
41:43
Jane Harrison: As I say, we haven't got time to go into the detail of this now, but i'm hoping we'll get plenty of chance to do this when we're looking at soil and structures and features in front of us.
41:57
Jane Harrison: Okay, then there's the finally there's this drawn drawn records and there are two sorts of drawings, there are plans, which is a bird's eye view and sections which are recording those all those vertical.
42:11
Jane Harrison: Vertical cuts through layers which you have very worked hard to establish as you've been digging.
42:19
Jane Harrison: on the backs of the context sheets you'll quite often do drawings of just the context that you're working on and but quite a lot of the plans. Jane Harrison: That are done to scale like this one, you can see in front of you, which is a scale drawing of those pips that I was showing you earlier, often they include several contexts and and. Jane Harrison: Quite often they'll be of one phase of activity and but sometimes i'll include a number of phases and they'll be.
42:49
Jane Harrison: picked out in different colors in order to show how things relate to one another and they're very good for showing horizontal relationships and showing for features and they should be read in conjunction with sections and here you can see.
43:06
Jane Harrison: Some biggest planning using a one meter Square and planning frame and me, doing the same up there.
43:16
Jane Harrison: And this, you can see that I just gave you that to show you this is, this is what this plan is depicting and.
43:23
Jane Harrison: Partly also to say, think about how a photograph can capture a certain aspect, but what the plan does is allow you to interpreted and capture other aspects, and so the two work together, I don't think they're mutually exclusive.
43:41
Jane Harrison: And here, you can see.
43:43
Jane Harrison: There are various as with the contact sheets, there are various things that that you follow various.
43:50
Jane Harrison: Ways of depicting things when you draw on site and there's always a book on site to show you how to do that different sites have different conventions, but as long as they're consistent that doesn't matter.
44:03
Jane Harrison: And it sections, of course, a really important for understanding the relationships that underpin our interpretations of the site.
44:13
Jane Harrison: And you remember that photograph I feared, you have the big advantage storage pit impossible. Jane Harrison: To photograph the section of that it was too deep and too much in shadow, so the scale drawing is essential and that's the scale drawing of the of the cut through.
44:30
Jane Harrison: That pit which gives you far more information to add into the photograph and and here you can see people busy section drawing in that little set of pitch there and here's a lovely section drawing of.
44:46
Jane Harrison: The foundations of a little Chapel and you can see that that this is really interpreted the the the foundations, because these dark lines are showing different phases of building and so you can see that there have been changes and alterations to to the building.
45:06
Jane Harrison: And this is just a little slide that shows you how you do a section drawing where you you put a level line across it and you're measuring up and down in order to create a a scale picture.
45:18
Jane Harrison: Of that, in this case and on he killed, which is just lovely colors as partly I like this slide just because it's so pretty.
45:28
Jane Harrison: Okay i'm going to stop now, because he is going to chip in for a little bit and then i'm just going to finish up with a few minutes to talk about ways in which we try and understand archaeological stratigraphy to set us up for our discussion in a couple of weeks time so over to you.
45:51
ian: Thanks Jane i'm in the last talk, I gave you some headline reasons, about the way that.
45:59
ian: kind of a pretty handy, by the way, i'm good just got a message saying my Internet is unstable okay right good i'm as any problems if you can give me away Jane. ian: And so, yes, and the last talk, I gave you some headline ways in which geology and archaeology interact with each other, and what I would like.
46:16
ian: To briefly to consider in a little bit more detail about the relationship between the physical our artifacts and the geological source. ian: And, and also to look about to talk about student students to take roughly and the relationship between geological an archaeological stratigraphy so next slide please Jane oops sorry.
46:39
So.
46:42
ian: Thanks.
46:44
ian: So. ian: The reason for fit for talking about to the relationship between geology and archaeology. ian: is to if you'd like to tap into this mindful approach to the James talked about in terms of the digs so in terms of giving you some of the ideas about the sorts of things from a theological point of view. ian: But it's worthwhile having your in your mind when you're trying to interpret what was actually going on within the site.
47:05
ian: So one of the things that and particularly having ssd in your head and so insulting and dispersal is what is the relationship between the source and the manner of extraction from that source material which is then used to actually build the next picture, please Jane.
47:23
ian: In this particular case, a wall.
47:27
ian: So what are the sorts of things that we needs to consider in order to be able to understand that relationship so if we haven't got the next picture.
47:38
ian: which gives an example which I managed to get into time mouth priority over the weekend, which was absolutely fascinating and can highly recommend it. ian: there's some really beautiful structures in there and, in particular, there are some really wonderfully. ian: Whether to send stones and one of the things that you can see very immediately in this sort of things which is really useful to be able to observe are in terms of sorts of patterns, which you see within the stone.
48:03
ian: But also things around with the size of the grains the types of the grains the.
48:09
ian: angularity of the grain and the relationship between the different sizes, the grain, if you go to the next picture on added to that. ian: That, then, gives you clues about what the source of that material might be just wait for that one to come up. ian: And the next picture is was actually taken in King opens base so you can look out over the top of the prior and look down on to the beach there.
48:34
ian: You can actually see the stone on the beach there, and you can get an immediate flavor there, but the two are probably related to each other in some way. ian: However, it's only by going into the real detail around the grain size and the grain types and all those other pieces of information, you can actually be more certain about what that's that that salsas.
48:54
ian: And there's another another example, if I have the next slide please.
48:59
ian: This is location which some of you may recognize and which was a deal that was carried out a number of years ago.
49:08
ian: And I think i'm hoping that everybody's getting these slides it's taken a while, for them to come through my end. Jane Harrison: i've got the men.
49:16
ian: Right.
49:17
ian: Good excellent so i'm just going to keep on talking and assumption that most people can see them and so to see the next picture is of the medieval.
49:29
ian: what's been interpreted as a medical Chapel on top of the huge on lindisfarne with these amazing big slabs which you can see, on the surface here. ian: And if you look at the next picture and what you can see is that within those labs there are some distinct geological features and in this particular case, interestingly, some ripple marks. ian: from some 350 million years ago which help diagnose this particular stone is coming from from carboniferous source probably not on the island.
50:00
ian: So understanding these sorts of geological details are really important in terms of understanding what sorts of material might be.
50:09
ian: We can expect your face.
50:12
ian: And it's not only building material, but some of the more.
50:15
ian: Culturally significant items and i'm not pretending to understand precisely what all these artifacts are but from a geological point of view. ian: There is a mixture of materials here so bottom right top left you've got flint and the top left is some sort of igneous material really quite coarse grained so Platonic and the material on the bottom right.
50:34
ian: Is igneous again very fine grain and property volcanic and immediately by picking out those details about grain size, the interrelationship of the grain size and the texture and the surface of that you're immediately learning something about the material.
50:50
ian: And in these cases, some of these items will have come from very, very significant distances and they don't tell you about and source, but also about some of the process in the trade routes which.
51:02
ian: actually moving these these artifacts around the next slide place.
51:10
ian: And also ceramics which are almost inevitable this, I have to admit, is one of my pieces of pottery and that's in terms of understanding the source of this.
51:21
ian: That, for me, the source of this was an online shop so pottery cross based in Stoke on Trent. ian: You can trace that back out words to the location of the place which were used in order to produce the particular type of clay, which are used to this pot. ian: and probably from locations down in in different parts of code or some for the China clay some for the ballclub which would have been admixed to produce to the particular clay.
51:45
ian: The point being here is that you can do exactly the same things with ceramic artifacts do you find on site as well, so that by. ian: Having an understanding and good observation of what you can actually find with no ceramic materials it tells you something about what the source of that material and some really useful archaeological information.
52:04
ian: So the next slide please.
52:09
ian: And so I think that's probably enough for that artifacts of what it would like to do now is talk briefly about strategic.
52:14
ian: And it's been fascinating listening to James description of archaeology institute grubby I mean it's interesting.
52:22
ian: That there is a need to understand both the vertical vertical and the horizontal stratigraphy and there are lots of parallels between the way that archaeologists understand stuffy CAFE and the way in which geologists understand it.
52:35
ian: And so, yes, so geologists it's not just vertical sections, but also we need to understand the horizontal relationships between things and but for geologists quite often what you're doing is using different locations in order to be able to tie together and these broader, horizontal relationships.
52:52
ian: And in the same way that geologists will be using so here's a section and just underneath time mouth primary. ian: where you can see there's a bottom unit, which is distinctly different from the top units, the bottom unity's read and and very blocky, whereas the top units. ian: And this much yellow and it's got these very broad fine grained angled stroke patients going across it so you can quite rapidly design and broad units, if you look more closely, you can see that there's another.
53:21
ian: crushed very red unit between those two and then you can start to break out different units within that So if you look in the bottom unit, you can see you've got seven. ian: boulder slightly teardrop shaped units intubated with some final grade material, and you can start to break down the certificate in in the same way and if you're not just. ian: us very similar types of combinations of drawing and detailed observation in order to dry out and understand what it is actually going on here.
53:52
ian: And, in contrast to the archaeological interpretation and structure graphic sequences and time is also important in the relationship of time and again. ian: In general, the bottom units over the older ones, and as you go up the section you'll be coming up through younger and younger units. ian: But if you want to tie down the time more precise T, rather than using artifacts geologists will be using fossils and rather than using carbon dating.
54:21
ian: which we can use for 10s and hundreds of thousands of years, we will be using. ian: Things like potassium are gone and strontium rubidium neodymium scenario and lead us at home dicing to give you that the time periods of millions 10s and hundreds of millions of years in order to understand the nature of these rocks.
54:40
ian: So why is it important in any sort of way I thought it might be interesting to understand the relationship between geological archaeological strategic fee if we go to the next slide. ian: And by understanding the geology that underpins a particular archaeological site, that is how we're going to start to understand the relationship between. ian: those parts of a landscape which are created through natural processes and those which are created through anthropogenic process.
55:11
ian: And the interaction between those two so here's our other wonderful site our little song and which shows. ian: A cliff face, which goes from quite distinct geological rocky material in very well defined layers which, as you progressively got the cliff you'll see gradually breakdown in turn into. ian: crumbled mess, which, as you go further up into the into the very top of the cliff you'll see is very loose unconsolidated material.
55:40
ian: And what we're going through here is a combination of hard rock geology a hard rock which has been broken up by a process of icu so cycles of following and freezing and then at the top we've got a.
55:54
ian: pile of place your material and even above that you will then have a soil profile, which is developed based on that and basically all material and. ian: A biological layer, if you like, that's the starting point for understanding what it is you're cutting into when you're actually looking at an archaeological dig.
56:15
ian: And if you look at the next slide please.
56:18
ian: And sometimes that interaction is really quite fascinating and what i've got here is a cross sections through a layer where you've got at the bottom I sandy layer and then at the top of the movie buff that you've got which is labeled as a tsunami pop deposits.
56:36
ian: were a really catastrophic the geological event has happened, which is ripped up PE class mixed it up with sand and then dumped it all in a layer ian: And then another layer of Peters grown over the top of that, and then the side horizon over the top of this. ian: And this is really quite interesting and particularly in the context of one of the digs which you can find on the coast.
56:56
ian: Around the Jewish Bay area where you have a geological strategic WiFi which has then been dug into with anthropogenic intervention in the iron age, which is then been covered by a natural event in the shape of food tsunami which is then followed by another sequence of.
57:17
ian: People soil development or in sand coverage in that particular excavate excavation, so there is this interaction between geological an archaeological anthropogenic. ian: Strategic WiFi which I thought it would be interesting, just to point out to give you something to contemplate when you're traveling away.
57:36
ian: And just final slide.
57:40
ian: This is very happy man who's got to the bottom of the archaeology and it's discovered some very exciting geology which I mentioned on the last. ian: dig so a very thin layer of archaeology on top of. ian: Some very hard specific geology and you can just about see some holes in there which are actually gas bubbles which formed in the top of the wind still there, on top of the heath which gives some really fascinating geological information about about the geology that you can find there.
58:09
ian: Great Thank you Jane i'll stop there, I have i've done less than 15 minutes left. Jane Harrison: that's great thanks Ian.
58:17
ian: Welcome Jane Harrison: Can you all hear me again.
58:21
Jane Harrison: Okay, so. ian: um. Jane Harrison: I talked about. Jane Harrison: various ways of doing and recording strata graphic excavation and which is taking the site apart in the reverse order to that which was created in so excavating the youngest first going in reverse order and.
58:45
Jane Harrison: structure graphic excavation time to do that is the best way of helping us to try and understand what might have happened. Jane Harrison: And I mentioned that the the sort of the unit of of stratification so the unit of archaeological stratigraphy is this thing called the context which can be a layer deposit a filler cut.
59:05
Jane Harrison: With each of those numbers that that those contexts, representing an action or a group of actions that you can't them separate like creating a rubbish dump, for example, and in some cases, you can. Jane Harrison: And this particular meeting or rubbish dump you can see, the different sorts of deposits that have gone into making it up and that's why you can see in this section so many little white tags with context Members on which are.
59:38
Jane Harrison: Are the labels for the descriptions of all these different deposits in in the section.
59:46
Jane Harrison: And stratigraphy is how we read the sequence of of context now.
59:52
Jane Harrison: There was a an archaeologist called ED Harris who is working in very, very deep urban stratigraphy in Winchester and quite some time ago now, and and he wanted a tool that would help him to unravel the complicated relationships between.
1:00:11
Jane Harrison: The features that he was finding and this really deep and complicated layer upon layer through hundreds and hundreds of years of urban living. Jane Harrison: and his way of helping to understand that is a thing called a Harris matrix. Jane Harrison: And Harris matrix is a diagram matic expression of all the relationships on the site and the great thing about it, and the reason why i'm introducing it to you or you may already have met it i'm sure many of you have.
1:00:42
Jane Harrison: But the reason why i'd like us to try and chew on this is it's a brilliant way of making you think, making us think about how the site is put together. Jane Harrison: And it's based on the geological lot of superposition that if a curve is be be was deposited first so be as older. Jane Harrison: So of context one over lies even partially context to then to his earlier.
1:01:07
Jane Harrison: And so that gives you an order of depositing so that up as a younger and lower less older broadly Of course there are exceptions, but we weren't going to those tonight. Jane Harrison: And there are other laws that that help us sort of untangle austerity griffey. Jane Harrison: One is that archaeological layers which are not solid when they were deposited will tend to settle into a horizontal layer
1:01:31
Jane Harrison: And that, if a lead isn't bounded by something originally by our fence or a wall or something it will tend to further off down to a sort of. Jane Harrison: thin edge, and so a vertical clean edge will need explaining and there's none this law of succession that a unit of archaeological to take her feet.
1:01:54
Jane Harrison: takes its place in the sequences to to grow feet from its position position between the earliest of the unit of the units above it, and the latest below it that's sort of logical. Jane Harrison: and common sensical um but it's sometimes quite hard to apply it now, this is a Harris matrix, this is what ED Harris.
1:02:16
Jane Harrison: the sort of thing he was using except with hundreds and hundreds of contexts to explain his urban's to take WiFi and you can see that each of these little rectangles. Jane Harrison: represents one of those events one of those contexts, with its unique number it's labeling number inside now context numbers don't. Jane Harrison: Are not values and all they are identifiers so then numerical sequence has got nothing to do with the sequence of the events on site.
1:02:50
Jane Harrison: So here, you can see we've got bedrock and we're looking at the South and North face of hadrian's wall. Jane Harrison: And so we've got the we've got the south face at the curtain wall built onto bedrock and the north face built onto bedrock. Jane Harrison: We can't collect them directly, because actually the two bits we were excavating were separated by the thickness of the wall, so we haven't got a direct.
1:03:17
Jane Harrison: Physical relationship between the two faces and themselves and then above the wall you've got subsoil mixed with backfill one collapse and turf that's formed over it, a spoil heap another collapse and that's all happening on the South face and on the North face you've got two.
1:03:39
Jane Harrison: different sorts of collapses earlier and later, but they're joined, because both of them are covered by the turf and the top saw that we took off so that actually represents in a diagram what we were unpicking on site. Jane Harrison: And that's quite a straightforward one they can be quite complicated and here's just a diagram at a slide that explains how we put together the Harris matrix a bit more.
1:04:08
Jane Harrison: And and it's a way of showing what is on top of the context you're working on and what is underneath it. Jane Harrison: And this is chronologically and and what might cut so if someone's like a post hole into the lair you're dealing with and or, and so what cuts the soil, or what it is cut by.
1:04:30
Jane Harrison: So you're getting that chronological sequence, and there are various relationships that you depict in your diagram This is one this context one overlays two so one is later than two, and this is what they would look like in a section.
1:04:48
Jane Harrison: One is the same as to sometimes you can you can find out later on that two areas you're digging actually the same thing.
1:04:56
Jane Harrison: And here we've got a little Harris matrix which is depicted in this little section drawing you've got a laugh three and you've got these two sort of em. Jane Harrison: dumps and materials material on top of them, which have no physical direct physical relationship, so what this says is these two don't have a direct physical relationship, but they're both later than.
1:05:19
Jane Harrison: The last three and then they're all joined together join together buy the latest the the earliest of the deposits, which is left for which is on top of both one and two and so has a slightly different.
1:05:35
Jane Harrison: setup there so that's a sort of basic relationships in the Harris matrix and i'm giving you sending you this exercise to do for next week. Jane Harrison: And with with the sort of answers, as it were, and so i'll just talk through this for two minutes and then i'll stop and you'll get these to think about, but the whole point of this is that.
1:05:59
Jane Harrison: it's all about understanding and thinking, and when you start to engage with this kind of thing, and you start to really think about. Jane Harrison: Okay, what has to have happened in order for this to be like it is when i'm digging it you become a better digger and it might sound a bit. Jane Harrison: complicated, but actually it's it's a way of making your digging even more interesting and I think everybody.
1:06:25
Jane Harrison: digs better when they dig with some understanding of how things are recorded and what you're trying to to tease out of the thing you're working on. Jane Harrison: So we've got what we've got here is natural subsoil, so this is a vertical section through a little pit or ditch sorry and.
1:06:45
Jane Harrison: The natural is a given a context number 005 then some point, someone comes along and dig a ditch so we're just looking at the profile of the ditch it goes backwards and forwards in front of us. Jane Harrison: And the action of digging out of that ditch is a negative action it takes away material from the site and but it's got to have a shape it's got to be described so it has a contact number.
1:07:11
Jane Harrison: Then the ditch begins to silt up naturally and and that's given a number and described and then it's filled up quickly and by people who want to level the site in order to do something else. Jane Harrison: And then we've got the topsoil forming on top and and quite often you'll find in Harris matrices that positive contexts where things are added like deposits and less will be in an oval and the negative ones, the cuts where you're taking stuff away will be in a rectangle.
1:07:40
Jane Harrison: And what i'm getting I asked you to do is to think about creating a Harris matrix for this section and giving you the answer to this one. Jane Harrison: And i'm giving you some other ones to think about and also for you to try and think about what could have happened between the ditch filling up and this topsoil forming and we'll talk about that as well in the seminar now i'm going to stop there, and you've had enough of me by now.
1:08:08
Jane Harrison: But I want to to stress that that all this is not to kind of.
1:08:15
Jane Harrison: mystify the process, because actually it is very clear, everybody can do it i've worked with all sorts of all sorts of. Jane Harrison: different levels of experience and everyone can record to the highest standards and learn to dig better and better as they think more about what they're doing an excavation is. Jane Harrison: To a certain extent, the essence of archaeology it's this unrepeatable process that.
1:08:39
Jane Harrison: encompasses the thrill of discovery with meticulousness and the challenging of in town challenge of interpreting it. Jane Harrison: you're confronting the physicality of the past it's it's manual and it's thoughtful. Jane Harrison: And it's teamwork with care and imagination and once you've made that decision that we talked about last time about where to dig what you get from it depends on the quality of the sorts of things we've been talking about tonight Okay, I will stop now.
1:09:10
Jane Harrison: Okay, was there any anything in the in the chat.
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