Geology and preservation

[GCampbell10]

At the event (site) level we want to record:
1 project name
2 project code
3 organisation undertaking the work
4 dates the work was undertaken (project duration)
5 location
6 Report reference (that is the overall report reference)

These fields are recorded as below in OASIS V

project name**: collected by OASIS and mandatory
project code: OASIS collects both a site code and a project code. These are not mandatory
organisation undertaking the work: collected by OASIS and mandatory
dates the work was undertaken (project duration): collected by OASIS and mandatory
location: OASIS collects the site name and X/Y or extent (mandatory) and then generates the other areas such as "City of York" from spatial lookups
Report reference: collected by OASIS but is not mandatory

The information above can be pulled in into the module as a "view", so the person entering the data can see what has been entered for that

It has been suggested that we also record the geology of the site. For our first discussion we want to explore this further. To get us started here is your first question:

The OASIS plus geophysics module uses the British Geological Survey (BGS) Web services to pull in drift and solid geology based on the location of the site. It also allows the user to to put in their own notes to describe variations etc

Do we want to do the same for our module?

[TinaRoushan]

Hi there. While useful, I don't think geology is of essential relevance to the proposed module. Therefore if it was included, I would lean towards the option of automation, rather than an additional field that specialists need to fill in. Open to other views though.

[RuthPelling]

If it can be automatically populated from BGS it is useful and worth including. While I might not search on geology, it's something that would be useful to see if I did search on something else (depending on what we include for other fields of course), and it would have implications for bone preservation particularly.

[TinaRoushan]

Yes I'd agree!

[MikePapaWhisky]

I think filling in geology data is definitely something that will become either ignored or, if its mandatory, serve as a barrier to adding data. Certainly if it can be automatically pulled in, then that could be useful. There is the issue, however, of how we define a site. In the commercial setting we routinely undertake large, often linear, excavation schemes that may span multiple geologies. Should these all be recorded? That might be meaningless as different archaeology may be restricted to certain geologies. This also has implications for how the BGS auto-complete will work - is it based on point data? I would have thought much of this would be covered at site-level anyway, and I wouldn't have thought it too relevant for the Plus Module??

[RuthPelling]

Hopefully geology is recorded at a site by site level by the project anyway in some capacity. There is a clear difference between site and project - this is recorded in Oasis, and it's standard practice to break linear projects down by site. Of course some single sites are long and thin so have a from and to grid-reference - I think Oasis deals with this. If an automated system was in place, the BGS data would be pulled in by grid-reference.

The question then is, is it the job of the oasis + module to record geology or should it be recorded at a higher site based level? If it's already there why repeat? What we actually need to think about is the search engines and where they pull data from.

[PolydoraBaker]

I agree with automation as this would avoid double entry but enable access to geology data. I find it useful to know about the big picture of site geology, solid and drift, to inform my understanding of preservation, and contextualise unusually good/bad preservation which can be influenced by context type/fills. Also may be useful when contextualising wider patterns of faunal distributions.

[MikePapaWhisky]

As well as the list of six items above, I would consider adding the stage of the project. WSI, DBA, Eval or Mitigation. These will often be down by different companies with changing scope of works and area of investigation through the project life-cycle.

[GCampbell10]

In OASIS the different interventions on a site or as part of a project are/ can be entered separately. An excavation is an event at a place (the site). The type of event is part of the main record and is chosen from a drop down list linked to the Event Thesaurus https://www.heritage-standards.org.uk/wp-content/uploads/2021/02/Event_alpha.pdf .

This thesaurus separates out events into non-intrusive events (e.g a Desk Based Assessment (DBA)) and an intrusive event (e.g. an evaluation, watching brief or excavation)

[RNicholson-enviro]

I agree with the general sentiment that it isn't essential, so would only be worthwhile if it could be added automatically. Otherwise, as said above, it could act as a disincentive to entering data. Also agree with the comment above re. entering Project type - eg Evaluation, Strip/Map/Sample, Borehole or Excavation as the level of recording will vary depending on the stage/type of project.

Re the event, site level - Project name can be problematic as it may change between different stages of the same project in our organisation. site code should be mandatory and museum accession code would be useful if known.

[wsmithMOLA]

Hello everybody - I have joined this very late - but also agree with the comments RNicholson-enviro - on automatically populating BGS underlying geology info & Project name issues.

Would also just add that certainly geoarchaeologists could amend/ add more detail and I suspect would be better placed to do that for site geology on their own input page - rather than via archaeobotany/ zooarch/ etc...

[RuthPelling]

Re naming - Oasis already deals with this so if the + module is linked to an existing project it's not a problem. It just needs to be consistent within a project. The record will be linked to an HER number eventually.

[GCampbell10]

Question 2: What about waterlogged Deposits?

One of the reasons we are interested in geology is because of its effects on the preservation of biological remains of all kinds . It helps us to know what to expect at a site and in formulating sampling and recovery strategies

Recognising the limits of knowing the geology of a site on the broad scale see @MikePapaWhisky would it be useful to know whether permanently waterlogged deposits (anoxic deposits) were encountering during the event at a site?

This could be a Yes/No Field. If the person entering the record entered Yes then a further field could appear which would provide an opportunity (not mandatory ?) to add more detail. This could be a simple dropdown list specifying : 'only in deep features' (eg wells. ditches, palaeochannels) and also something like 'generally distributed'. We could also add the shallowest depth at which such deposits were encountered.

What does everyone think?

[wsmithMOLA]

I'd just like to add that deposits can be waterlogged but unproductive for certain classes of remains - David Smith & I have had good insect results with relatively poorly preserved/ sparse archaeobotanical material and visa versa. We've also had situations where compaction (so very deep deposits - thinking of Stonebow York) has meant that lowest deposits are so damaged through compaction (?weight of hydrated overburden) they're unproductive, despite being waterlogged.

In general think Ruth's points - that in the WSI seeing what previous work has been done in the area would most likely identify the possibility of waterlogged deposits for sampling strategies.

[DanaChallinor]

Apologies -since I missed the last meeting - if I have misunderstood some of the context of this discussion, but my thoughts on wood/charcoal are as follows:

• it is useful to know if there is waterlogging at a site (however useful/damaged - as this signposts to wood preservation), but arguably equally useful to know what/if charred remains were recovered if one is looking up comparable sites as a specialist. And I suspect that this information will be available at the next level? Therefore not necessary at the Site/Event level.
• Geology is different since it would be unchanged regardless of what archaeological material was actually recovered/analysed - but I agree with others that it would be better as an automated field or edited by geoarch specialists.

[MikePapaWhisky]

You could phrase this differently, as 'potential for waterlogged preservation'.

I'm not keen on the idea though. I think it's very important to record whether the [sampled] assemblage contains waterlogged remains. But to record waterlogged deposits that were encountered, but not sampled, feels like a slippery slope.

I feel (maybe I'm wrong) that the point of the OASIS+ module is to accompany archaeological information/data. If we start recording all sorts of things that might have been archaeologically significant, then we could end up introducing all sorts of biases. For example, if a waterlogged deposit is not sampled on site, will the environmental team always know about it?

There's a risk to trying to be all things to all people, so perhaps safest to stick the specifics of a particular assemblage?

[RuthPelling]

Yes, I agree with Mike and Wendy here - if no sample, there is no evidence of waterlogged preservation. There is also the risk that waterlogged deposits are present but not recognised, or as Wendy says, present but variable preservation, or that a site looks wet but doesn't have waterlogged preservation.Too many variables. The + module needs to record actual verified results. Future planning would then be based on factual rather than speculative information and if the factual data is not there, investigation is required to demonstrate waterlogging etc or not.

[GCampbell10]

Discussion Summary

1. We concluded that automatic pulling in of drift and solid geology using British Geological Survey (BGS) Web services was worthwhile but that this should not be put in by the record creator and that a qualification field giving further description is not required.
2. The consensus was also that we don’t record the potential for waterlogged deposits or the presence of waterlogged deposits within the module at the site level
3. It was felt that it would be better to record waterlogging at the assemblage level. For example, Waterlogged -Plant Remains -Roman.

Thank you everyone for taking part.