How should OASIS collect large area surveys?

If you are an OASIS user or potential user we need your comments on how the new OASIS system will record large area surveys.

The current version of OASIS was not designed to collect large area surveys and so does not cope with it very well. We think we can do better in the new system, but we need your help!

This is how things might be improved. Please use the comments section to tell us what you think.

© Museum of London Archaeology, Northamptonshire County Council

What scenarios are there? We think:

  1. Walkover surveys e.g. Windfarm
  2. Thematic surveys/studies e.g. Roman bath sites in the UK
  3. Linear projects e.g. Road/rail schemes
  4. Large geophysical surveys
  5.  Can you add others?

Recording and reporting:

We propose to:

  1. have the area of the project defined by a boundary polygon – either uploaded from as a GIS file (formats to be determined) or drawn on a map on screen.
  2. create only ONE record no matter how many HERs an event covers (this is not what happens now).
    • each HER would be notified of the project (if they had opted to be).
    • each HER can review the record and see who else had worked on it.
    • the record would be saved as successive versions if changes were made.
    • BUT: The release of the report to the ADS Library and the record to other external databases would not be stopped by an individual HER that had not reviewed it.

Other questions relating to investigation type:

Walkover surveys e.g. Windfarm

For Walkover surveys e.g. Windfarms – Is the boundary of the full extent of the survey enough in these cases or would smaller investigation areas within the larger survey want to be defined? And if so how?

 Thematic Survey e.g. Roman bath sites in the UK

We can think of 2 ways to do this:

  • Allow upload of a polygon for whole area – may be a region or even a country, but allow ‘sub polygons’ and sites to be included as well.
  • Do as for Linear projects below – have a parent record that covers the whole areas, then child OASIS records where the thematic survey had done further work. Individuals sites could then be passed on as monuments records.

Is there another way?

Linear projects e.g. Road/rail schemes

Large scale and long-running projects with multiple events.  

  • each event entered as a separate OASIS record
  • THEN: related to an overarching ‘parent’ project – should parent project be identified by the OASIS ID or something else?
Large Geophysical Surveys
  • Entered on a survey-by-survey basis and related to a parent record as above.

So in the interests of keeping this post short enough to read easily (too late?) we have not gone into great detail but hopefully have covered enough to generate discussion.

Will these proposals work for:

  • HER Officers?
  • Investigations Teams at National Heritage bodies (Historic England, Historic Environment Scotland, National Trust)?
  • Contractors doing large scale projects?

Tell us your thoughts!

10 thoughts on “How should OASIS collect large area surveys?

  1. Each event polygon should be exactly that. One event one polygon. So if the whole area was fieldwalked it should be one large polygon. If only three separate fields were walked they should be one event but three polygons.

    Will event polygons be selectable? if so, large polygons are annoying as they mask smaller polygons below. Perhaps if you’re using GIS, a layer for ‘landscape scale’ polygons could be created which could be switched off when viewing the smaller ones (which may not overlap).
    ‘Turning the plough’ is an example of a multi-county project.

    On a different topic but related to the extension of Oasis:-
    I think there does need to be some quality control with reports/data/projects which are added to Oasis. Particular those which are outside of the planning process.

    1. Thanks for the comments Caroline, the idea is that the person entering the project will either upload, or draw on-screen, a polygon of the boundary of the project. It will then be used to give a visual check on the location of the project for the person doing the data entry and be available to see on screen and download for the HER and other users reviewing records.

      I understand that the polygons might be large but they will only ever be viewed on the OASIS system as single projects, OASIS will not provide an interface for looking at multiple projects on screen but the data will be there for authorised users to download and use in their own systems. So the overlapping polygons issue should be able to dealt with by a user in their preferred fashion.

      I’m not sure I can answer you other point as it would be up to the reviewing HER to reject a report or record for a project that they did not feel was of sufficient quality. If the HER is not reviewing projects it could potentially be stopped at national level depending on country or go straight through to the ADS Library and other systems. If this is the case, however it will show that it had not been reviewed by an HER or equivalent body. I hope that helps clarify the situation even if it doesn’t provide a definitive answer.

  2. Hi Jo,

    I am interested in the history of landscapes and the recent history of archaeological recording of those landscapes.

    It seems to me that there are some surveys which include a lot of possible sites that become fossilised as definite sites by later compilers and then noted as lost sites when someone goes to look for them on APs or in the field. It is important that there is a field what allows sorting by investigator and or date.

    1. Thanks for the comments, it is a good point – OASIS collects the event information for the survey and has space to enter related monuments which were found, but the definitive record for the monument itself is within the HER and so it would depend on how the monuments within the large area survey were catalogued there.

  3. A response from my (an HER Officer’s) perspective:
    I think you’ve captured the main scenarios for large area surveys.
    I like the idea of only ONE record no matter how many HERs an event covers. For these sort of surveys, would the record be released into the ADS Library as soon as one HER (the first HER? the HER who covers the largest area?) has validated it? I personally think one of those options would be workable for HERs.
    I’m uneasy about parent/child records – but maybe that’s just the terminology. Most events that are recorded on OASIS are single, discrete projects, even if they are part of a larger scheme. I think parent/child events could get really confusing; and what would happen to the parent records – particularly if they are just events that ‘wrap-up’ other events – and therefore contain no real content (i.e. a report) themselves? I’d be worried about encouraging events to be created for the sake of it. Instead of Parent/Child records, how about just the ability to have a relationship with any other Event (and the option to record whether it is a parent/child/peer-to-peer relationship)?
    WALKOVER SURVEYS: The boundary should be the complete area actually covered by the walkover survey – even if that means multiple polygons (or multi-part polygons).
    THEMATIC SURVEY: For thematic surveys it is a lot trickier. If it actually surveyed the entire region/country, then it would be appropriate to create a polygon showing the entire country. However, most thematic surveys of this size (e.g. Roman bath sites in the UK) just study the known sites – therefore multiple (or a multi-part) polygons showing the extents of these sites would (I think) be the best way to record that this survey has looked at all these sites.
    By the way, I note you mention that “Individuals sites could then be passed on as monuments records.” It’s an interesting proposal to explicitly allow OASIS to record monuments; I thought that OASIS does not collect monument descriptions, so it’d be interesting to see how this would work. Maybe, by recording multiple polygons (as above) would negate the reason to do this?
    LINEAR PROJECTS E.G. ROAD/RAIL SCHEMES: Large scale linear projects should just have each event entered as a separate OASIS record (as above). I don’t think there is a need for any parent records per-se; see comments on parent/child records above.
    LARGE GEOPHYSICAL SURVEYS: Again, these should just have each event entered as a separate OASIS record (as above). I don’t think there is a need for any parent records per-se; see comments on parent/child records above.

    1. Thanks for your comments Graham, it is useful to get an HER Officer’s perspective on this problem. I’m interested in the collection of the relationship type between two OASIS records as well as just the fact they are related. I think this is a good solution to the problem as I agree that having parent records with no real content is to be avoided. Out of interest is it possible to record the type of realtionship between to events within most HER databases, so if an event is the parent or sibling of another. I appreciate you cannot speak for all HERs but it would be useful if to know if this is data that could be collected.

      Also the possibility of collecting extra information about monuments comes from two areas we are looking into.

      1) The Discovery and Excavation in Scotland form (which is being merged with the OASIS form in Scotland) records more information on sites within an event and we are looking at how this might be used in a merged form.

      2) We are looking at the possibility of concording OASIS records with current monument records at the point where the OASIS record is entered. We might do this by querying the Monument Web Mapping Services (WMS) available for an area and bringing back a list of monuments (with their monument identifiers) for the area of the OASIS event. This could be a very long list for a large area survey and we are unsure if this would overly complicate the event reporting or vastly increase its usefulness by allowing the person entering the record to select monuments were relevant to the event.
      As I say it is something we are thinking about at the moment and would appreciate others views.

      1. I can’t speak for all HERs, but I can confirm that the HBSMR HER software does allow each event to define one (or more) parent events and one (or more) child events. Hope that helps.

  4. A few thoughts from the Investigator perspective (within Historic England).

    As examples of large area scenarios I would suggest that aerial surveys, Historic Area Assessments and characterisation projects should be considered, even if they are comparatively easy to define by event polygons linked to the reports arising from the work.

    A more complicated scenario, going further than the windfarm walkover example, would be the multidisciplinary survey – different approaches applied at various scales to a broad landscape under an umbrella project. This might include aerial survey of many hundred square kilometres, followed by ground-based (walkover) surveys in selected areas, targeted earthwork or geophysical surveys, and perhaps other approaches such building survey, pollen coring or excavation. The approach here could be to have event records linked to each survey area which produces a report: so an overarching polygon for the broadest study area (covered by the project report) with smaller polygons or even points (linked as parent-child, or as siblings) for smaller individual surveys of various kinds, if they generated separate reports. Granted overlapping polygons are a nuisance, especially when the polygons are opaque, but it should be clear from the largest polygon that the project has further entries which can be teased apart.

    When you mention single event OASIS records for multi-site linear projects and large scale geophysical surveys, I assume that you mean for these to be linked to an overarching report, as without it there is no process of validation. Do you intend to allow the event record to be created prior to the completion of long terms projects, and therefore before the completion of the final report?

    1. Thank you for the comments Dave, it is an interesting scenario and it highlights the point that we have to find a happy medium between recording events in enough granularity for them to be identified as individual events whilst not over burdening the users of OASIS who have to enter the information.

      To answer your question: An event record can be started at any point in the project but would not be considered finished until the report was available, either uploaded to OASIS or sent to the relevant archive.

  5. Some thoughts on complex projects / surveys from Scotland.
    Boundary polygons
    Boundary polygons – ideally these should be captured electronically or created by the submitter referencing large scale mapped detail (but taking account of any third party Intellectual Property Rights in the underlying data).
    Drawing project extents freehand on screen should be discouraged as they cannot accurately reflect a study area. There are reputational issues over sketching rather than accurately defining areas and I certainly want to be able to re-use rather than redraw polygons.
    Regardless of the size of a study area, there should be an overall polygon defining the project extent with separate polygons for particular activities or events within that project.
    For instance the project polygon will define the extent of the development with separate polygons provided for each excavation trench or geophysical survey within the project area.
    For large area surveys there will therefore be a need to document separate events
    I agree that there should be a single boundary polygon for the Project as reported through OASIS – even if it covers more than one HER and that sign-off times will not be aligned – everyone works at different speeds.
    The need for Parent Records
    These should be essential for large scale projects with multiple site locations or long-term projects carried out over several years. I certainly want to be able to identify all field work relating to a large scale project such as a new road scheme or pipeline – no least because the archive received at Historic Environment Scotland may well be organised and catalogued by Project.
    I m not concerned about the terminology used to describe the relationship between OASIS records but it must work for those entering the data.
    Geophysical Surveys
    If the surveys are conducted as part of a large scale project, then there should be an OASIS record for each survey report (with a link to the overarching project)
    The technical metadata required to document each technique used on a project should be recorded – ideally with a copy of the survey grid extent appended.

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