Tag Archives: excavation

Excavating cremations

Warning: Images of human remains feature in this post

Several of Allen Archaeology’s recent site excavations have revealed a particularly interesting aspect of ancient mortuary practice: human cremation burial urns.

Some of the pots we have retrieved date from the Bronze Age, Romano-British and Anglo-Saxon periods, and are known to have been used as early as the Mesolithic in Britain (c.5500 BC), although this method began to fall out of favour following the widespread adoption of Christianity in Western Europe.

Early Anglo-Saxon (5th–6th Century AD) stamped cremation urn found near Fakenham, Norfolk

Unlike modern cremations practices that produce ‘ash’, archaeological cremation burials consist of pieces of bone of varying size, often being quite large and identifiable. The reason for this difference is down to the processing method. Whilst modern crematoriums use industrial furnaces (that burn at temperatures of 870-980 °C) and a machine to pulverize the dry bone fragments into a fine powder, cremations in the past would have been performed much differently. The deceased would have been placed on a wooden pyre and required constant attention to keep the fire burning, particularly when the weather would not cooperate (surely not?!). The result is a lot of small chunks of cracked and discoloured bone which are then placed (in part or altogether) into a pre-made urn, and buried.

Due to the fragility of the urns and their importance as a burial, they are carefully removed on site and sent back to the office to be excavated – this happens exactly the same way as on site, but at a much smaller scale! The contents of the urn are removed in levels or ‘spits’, and records including photographs and drawings are taken before and after the removal of each cross-section and full layer. Due to having to work in a pot with a diameter of roughly 13cm compared to a pit or ditch of 1 to 2m, a completely different set of tools is needed. Lay down the shovel and trowel, and pick up your clay art tools and tweezers! Once the bone is removed it is passed through several sieves (10mm, 5mm & 2mm), with the remains of varying sizes weighed rather than counted. These are then bagged according to their size, with any recognisable elements bagged separately.

Excavating a cremation burial

So now the bones have been excavated, what can we tell from them? More than you think. The colouring of the remains, the amount the bones have warped from their original shape and their completeness can reveal information about the temperature of the fire, if there were any problems during burning (such as weather or incomplete incineration), how the body might have been placed on the pyre and whether the body was clothed or burned as dry bone. Duplicate elements of bone will also alert you as to whether more than one individual is present within the urn, as can the cumulative weight of the fragments.

Also, other remains such as macrobotanical or charcoal fragments can aid in the interpretation of the pyre construction, whilst ‘grave goods’ given to the cremated individual might also survive.

Fragments from a Romano-British cremation urn burial found at North Killingholme, Lincolnshire

Best site hut biscuit with Mia

What is your job role?
Project Officer

Loving life in 2008

How long have you worked for Allen Archaeology?
For nine years in September

How would describe your excavation technique?
Once upon a time I suppose it could have been described as fast and furious, but with a bun in the oven the spade has been put on a shelf for a while

How long have you been working in archaeology?
About ten years

How did you get into archaeology?
It has always interested me, but I never considered it an occupation until I somehow found myself with a degree in it and thought, why not? I started off in Ireland and a year later ended up at Allen Archaeology.

What is the best thing about your job?
Probably that I’m still learning new things with every job. In the beginning, everything was new and the learning curve steep and interesting. When I started it was a really small company with less than a handful of people and so I got to try everything almost in one go. As the years have gone by, different staff and people with different skills, have helped me deepen and broaden my own.

Specialist skills?
I don’t know about special, but I’ve done a few building surveys throughout the years. I believe I wrote a few clay tobacco pipe reports as well, but that only lasted for a short and sweet time; they’ve got someone much more skillful to do this these days.

Best site hut biscuit?
Well, any biscuit or cookie with a gooey nougat centre rates high on my list, although their lifespan tend to be quite short in my presence.

A roundup of the week

It’s been a busy week at AAL so this weeks blog is a little round-up of what we’ve been up to.

Warning: Images of human remains feature in this post

You might have already seen the excitement on our site at University of Lincoln. During monitoring works we uncovered human remains dating from the Roman period close to the River Witham.

Tobin has been visiting a site in Cumbria where we have been undertaking a Watching Brief

Rachel working on Damian's site near Peterborough

Damian has had a team out working on an evaluation near Peterborough.

The geophysics team enjoying a break in coastal Lincolnshire

Rob has been out with a team to start a large geophysics project on the Lincolnshire coast where they’ve been contending with a lot of weather but enjoying the location!

Fee’s been working hard in London

Al is dealing with challenging conditions in Brentford

Work is continuing on our “big” project in Market Harborough where the team are undertaking an open area excavation

Bryn has been working hard processing environmental samples

Yvonne has joined the archives team and is getting up to speed as Cova heads off on maternity leave

Nasha has been busy editing reports and dealing with publicity.

Josh has been analysing lithics for a specialist report

What is a watching brief?

Following on from our post “Evaluation by trial trenching” this weeks post is going to explain what a “watching brief” is.

A watching brief, scheme of works, or programme of monitoring and recording, is usually the final stage of archaeological investigation, and may follow on from desk-based studies, evaluation trenching or excavation. Usually one archaeologist works closely with the groundworkers, monitoring their excavations which might be for foundation trenches, services, drainage or landscaping. The archaeologist records any archaeological remains that are exposed.

A watching brief can be applied to a scheme of any size. For example, on a large linear scheme such as a pipeline, it can follow stages of non-intrusive and intrusive survey that have (hopefully) identified and investigated the areas of greatest archaeological interest. The watching brief is used as a ‘failsafe’ to double check stripped areas where little or no archaeology is likely to be present. This often requires a degree of patience – watching a machine strip topsoil for kilometre after kilometre without finding anything! It is also essential to take a good book, for any delays as spoil is moved and machines are repaired or refuelled.

A small team working on a watching brief for a linear scheme. A good book is essential!

Many small watching briefs are undertaken as the only stage of archaeological work on a site. For example they might take place during the groundworks for one or two new houses or an extension to an existing one. These clients may never have dealt with archaeology before and may never need to again, and so we are often asked ‘What happens if you find stuff? Will it stop the job?’ The answer is almost always no and on the rare occasions that unexpected or significant archaeology is exposed, additional staff can be deployed to site to limit delays.

Watching briefs can be interesting and challenging. Working on a busy construction site you need to keep your wits about you and have a keen understanding of health and safety. We inspect and clean the exposed sides and bases of the foundation trenches to piece together the evidence provided by these cross sections through the site, tying together fragments of field boundary ditches, pits, landscaping layers or other features to gain an understanding of the area. We will also recover dating evidence, such as pieces of pottery, whenever possible.

When the archaeological fieldwork is complete, the developer will carry on with their building programme and we still have plenty of work left to do, cleaning and analysing any finds from the site, preparing the report and depositing the project archive with the local museum to sign off the client’s archaeological condition and make the results publically accessible to this and future generations.

The AAL trainee scheme

I graduated from University of Bournemouth in the summer of 2015. I had worked on some research projects as part of my degree and had some experience of volunteering, but no commercial archaeological experience. Without experience it’s normally very hard to get into commercial archaeology, as some of my fellow graduates can attest to. I was lucky enough to apply to Allen Archaeology at just the right time and was offered a start as a trainee in November.

Working at Lincoln University

I started out in the office washing and marking finds. These are important skills but they can get a bit repetitive so I jumped at the opportunity to go out on site for the first time – to Whisby quarry. It was certainly a bit of a culture shock compared to the academic digs I’d been on before! Work was fast paced, colder, muddier and harder work. However, the site was fairly straightforward and with some help from my supervisor Damian Podlinski I got through it all right.

From there it was time to move into Lincoln, where the company was digging in preparation for construction to start on a new building for the university. The site was next to the river and fairly deep, which meant it was under water most of the time. So again, wet, muddy, cold. We had a great team though and halfway through the site we’d figured out a system that made light work of it.

“Work is fast paced” this site in Yorkshire demonstrated how quickly I could work given training

Perhaps one of the most informative parts of my traineeship was the last week; I was taught GIS in the office by the GIS guru Chris Casswell. Although I knew about the program, I’d never used it before and after some initial hiccups everything went smoothly. As an added bonus using GIS didn’t involve getting either wet, mud or cold in January!

At the end of the traineeship I went to broaden my range of experience by working for another archaeological company in London for 5 weeks before returning to AAL in March. Since then I’ve worked on a number of different sites and types of job; I’ve done watching briefs both alone and supervised, I’ve excavated Roman settlements and most recently I worked on a medieval building near Lincoln Cathedral. No doubt there will be more interesting sites to come – and some cold, wet and muddy ones but the trainee scheme has allowed me to get my foot in the door working in commercial archaeology.

Evaluation by trial trenching

An evaluation by trial trenching is sometimes requested as a condition of planning consent, or more frequently since the advent of NPPF, on advice from the planning authority prior to the application being submitted or determined. The condition or advice is based on the likelihood that the site holds archaeological potential. The applications vary but could for instance concern a small or large scale development that involves any below ground impacts such as housing developments, industrial developments or landscaping.

Company director Chris Clay watching a trench being opened

Several factors play a part for allocating the trenches within the development area. Some may be based on geophysical survey results that target certain anomalies of archaeological potential, whilst others may be strategically placed within the area to try and determine the extent of any potential archaeology. How much of the site that will be sampled is usually down to the local authorities and their policies, but tends to vary between 2% and 5% of a development area GPS survey equipment allows us to target our trenches at agreed locations to centimetre accuracy.

The majority of trenches are excavated by a mechanical excavator fitted with a smooth ditching bucket. However, to everyone’s dread, there are those cases where hand dug trenches are the only way forward! In either case, it is up to the supervising archaeologist to decide on the appropriate depth. Either this will be on the first significant archaeological horizon or when the natural geology has been reached.

Once open, the trench is ready to be investigated and recorded. If there are any archaeological features, these will be excavated by hand. Any finds will be retained, bagged and labelled and soil samples may be taken to identify the feature’s function or to give information about the past surrounding landscape and environment. Plans, section drawings, descriptions of deposits and further photographs will also be taken.

When all the trenches have been recorded, they are backfilled and the post-excavation work can begin in the office. Finds are washed and marked and submitted to the relevant specialists for detailed analysis.

After all the data has been compiled and a report has been written and sent off to the client and the local planning authority, a decision will be made by the county or city archaeologist for that area, whether any further work is required. If the results show the potential for significant archaeology, or features of archaeological importance, the evaluation may be followed by an open area excavation, where a large part of the development area is stripped down to the archaeological horizon. If the evaluation shows some more limited archaeological presence that requires further investigation, but none that warrants an excavation, the evaluation may be followed by an archaeological watching brief. This work will be carried out during the actual development groundworks.

Training at Allen Archaeology Limited

According to a helpful little counter that shows up on my employment record I have been working for Allen Archaeology for 2 years 6 month and 23 days. Nothing particularly ground breaking, but in that period of time I been fortunate enough to work on some incredibly interesting and exciting sites but I’ve also progressed from a Trainee Project Archaeologist to Project Supervisor level and in the process received a staggering amount of training and learned what it means to be a commercial archaeologist along the way.

Taking part in a field school at Nevern Castle while at uni

I have always loved history, but it wasn’t until I started looking at University courses that I realised that when I grew up (!) I actually wanted to be an archaeologist! So in 2010 I went to study Anthropology and Archaeology at Durham University, partly because it was something that I thought would be interesting and partly because they let me live in the castle. It was pretty good in that it gave a very comprehensive overview of archaeology, but like most archaeology degrees lacked in practical aspects; in fact there were no compulsory archaeological fieldwork modules as part of the course. Nonetheless, I left Durham with 8 weeks of field experience, and the overwhelming impression that commercial archaeology may not be something I really wanted to look into; it was a bit too cynical and our yearly “careers” talk made it seem like the commercial world was not an exciting one to work in. So when my degree ended I made the decision to take a year off, earn some money, and then go back and do a masters.

This plan however spectacularly failed. I moved back to Lincolnshire and got a call from AAL (a year after I had applied to be a volunteer with them!) asking if I was available to work and offering to employ me. I started in September 2013 as one of their trainee site assistants, with very little experience of what commercial archaeology was or what was expected of me.

I did have a trowel though; so it was a start.

Where I cut my teeth was at AAL’s colossal North Killingholme project (NKAM) and training was given on the job. I was told what I was expected to do and then left to get on with it; sort of like being thrown in at the deep end and “shadowing” the other project archaeologists when I needed guidance. There was no formal training plan but I think it was a pretty effective way of learning the basics, and there was always someone nearby to help when I got lost.

It was fairly simple archaeology to begin with, putting metre sections through Roman ditches, and the thing I remember most is continuously being squeaked at and asked by the PO on site “Are you happy with those edges?”. It turned into a bit of a game with all the other PA’s on site, lightly mocking this phrase, but it taught me how to excavate quickly and accurately and helped me progress into being a real Project Archaeologist. Learning how to record took me a little longer however, it was a whole new experience being shown how to draw to scale and how to trust my interpretations of features, but I got there eventually and was able to move onto digging larger and more exciting features, like ditch intersections, Roman Kilns, and ring ditches.

Excavating a skeleton in October 2014

That’s one of the things I enjoy about working here, that there is a lot of effort devoted to trying to training staff and to give everyone a rounded knowledge base; everyone learns how to work the survey equipment and is expected to be able to excavate and record a feature from start to finish, and everyone gets some experience in post-ex be it finds processing, writing context summaries, or producing figures. It’s something that I massively benefited from.

The next year was a massive learning curve and I received a lot of training beyond the practical skills I was still learning in the field. I got to handle a lot of the material remains that were coming from sites through washing and processing the finds and I started learning the basics of post-excavation work and about working with GIS programs by digitizing drawings and phasing sites. I spent a lot of time staring in frustration at muddy scans while digitizing plans and sections and at the array of pastel colours used to phase the NKAM sites, . It wasn’t always the most exciting things, but it defiantly helped me become a more rounded archaeologist, and made me realise the importance of properly recording and checking the work we do on site!

DIgging the ring ditch at North Killingholme

At the end of June 2015 positions became available within the company for Project Supervisors and, with the support of my line manager, I applied and was given the job as a trainee supervisor. Unlike my last traineeship, this position had a much more structured training plan and I was given tasks which needed to be signed off by various managers and project officers in order to check my progress. It was a little messy at first as there was still a massive hands on approach, and it took some time to actually be able to put the training plan in place for various reasons, but I started off in a safe place, back at Killingholme guiding our new trainees, before being sent off on some of my own jobs. Like before I started off small; with small scale watching briefs and evaluation sites which over the next few months gradually progressed into slightly larger jobs, with a few other team members to supervise. It took some adjusting to (and a lot of site visits and phone calls asking questions before I got my bearings!), but it was exciting and I got to work on some interesting sites and developed a particular interest in community based archaeology. I had enjoyed working on some of the previous outreach projects such as the open days at North Killingholme and at the Canwick Bomber Command Memorial site in 2014, so when I was given the opportunity to work on a few community projects run with the National Trust I jumped at the chance!

Talking to volunteers on a community dig at Hinton Ampner

What changed most with this new role, however, was the responsibilities beyond the fieldwork and learning how to manage a site, and I got the chance to develop more post excavation skills. I learned how to structure reports and produce figures and I spent a lot of time in the office repeating this process until it was second nature. Again it’s not always the most exciting thing, and some days it’s incredibly frustrating and I wish I was outside happily digging ditches, but it is worth it. There is a special sort of pleasure you can take in making a figure look pretty, or getting your teeth stuck into a particularly interesting site you are writing up!

I suppose what I take from all this reminiscing about the considerable range of traineeships and professional development I have experienced within Allen Archaeology over the past two and a half years, is that I’m incredibly proud of my achievements here and, despite a number of stumbles along the way, I am very grateful for the continuous support and guidance I have received at all stages, from everyone within the company. It’s made me the archaeologist I am today and I love my job, especially the community projects and the opportunities to be involved in new team members training, and I hope I give them even a little but as much encouragement and support as I received when I first started.

But I’m still learning.

And I may have realised that now I’m not always joking when I ask people on a site I am supervising if they’re happy with their edges….

Digital Techniques: Structure from Motion (SfM) Photogrammetry

Warning: Images of human remains feature in this post

If you’re involved in the heritage sector then chances are you’ve seen a three dimensional (3D) model of an archaeological site, feature or artefact that you can view and interact with on a computer screen or mobile device. It’s likely this was created using SfM, which operates under the basic principle that 3D structure can be resolved using overlapping images. Photogrammetry is the science of making measurements from photographs. Therefore, SfM photogrammetry is the use of photographs to accurately record 3D models from which measurements and details can be recorded. I could go into more detail regarding the technique itself works but for now lets just assume it’s tantamount to magic!

Capturing a collard urn

We’ve been exploring the possible uses here at AAL for a couple of years now after initially learning about its potential from the master of archaeological photography, Adam Stanford (http://www.aerial-cam.co.uk/). Initially we trialled the technique out in the field for the recording of skeletons and masonry because these are two often poorly recorded feature-types; that and our office at the time was somewhat unsuitable for artefact recording (to put it mildly) and my spare bedroom/dark room at home was full of kittens. What we found was that, if recorded properly on site, the technique allowed for a more accurate record of the feature from which a traditional illustration could be made and disseminated to specialists to aid in their assessment/analysis.

Example of a record using SfM on site

It also allowed us to revisit these features from the comfort of the office (the new one, not the old one) and examine them in closer detail than we had time for on site.

Masonry recording

By the time my fieldwork marathon was complete we had a new head office in Lincoln with plenty of space for us to experiment with SfM on artefacts. Trial and error was key here, and there were many failed attempts before finally working out a methodology fit for the task (credit must go to Hugh Fiske for providing the inspiration needed to complete this and I’m sure you’ll agree he’s made some beautiful models, http://www.archaeo3d.me.uk/)

Part of the company ethos here focusses on training for all, and as soon as we were happy with the workflow we began training others in this recoding technique. Currently we’re building up a portfolio of models so that in the near-future we can showcase them online for everyone to access, so watch this space.

Chris training Andrea and Charlotte in Structure from Motion

Archaeology in the commercial world

The discipline of archaeology is as old, or older than some of the finds we dig up every day, with the first documented archaeological dig dating to the 6th century BC when the Babylonian king Nabonidus led excavations to find the earliest phases of several palaces and temples in ancient Babylon.

Roman colonnade discovered in Lincoln in 1878

In recent history, the discipline of archaeology began as a gentlemanly pursuit, with the profession gradually developing an increasingly scientific approach thanks to a number of scholars in Europe and America during the 19th century, such as General Pitt Rivers; a British soldier and adventurer, who brought military precision and organisation to the process of archaeology. Nevertheless many archaeological discoveries were still chance finds during development. In the 20th century, another military man, Mortimer Wheeler, also employed military precision in his numerous excavations in Britain and India, and helped bring archaeology to a mass audience through numerous TV and radio appearances.

General Augustus Pitt-Rivers 1827-1900

As the pace of development increased in the post-war years, the relationship between archaeology and development changed. It became apparent that many important archaeological sites were being lost, with little or no record. This led to the evolution of a whole new discipline of ‘rescue archaeology’ or ‘salvage archaeology’, which introduced new techniques to maximise the recovery of archaeological data with the limited time and resources available. This led to the development of a number of archaeological organisations, often based within and partially funded by local authorities, as well as by developers, to undertake these rescue digs.

Legislation was slow to catch up however, and it was not until, in 1990, with the implementation of PPG 16, the ‘polluter pays’ principle was applied to archaeology and development. This piece of planning guidance placed a burden upon the developer to ensure that archaeological remains at threat from development were adequately recorded, with that funding coming directly from the developer, and the work more often than not being secured by planning conditions. In some local authorities there was a feeling that more work should be undertaken pre-determination, both to limit future delays to construction programmes, and due to the concern that should important remains be exposed, there was little chance to offer them legal protection or record them adequately once a grant of planning permission had been issued. This finally manifested itself with the release of PPS5 in 2010, which placed greater emphasis on providing more information on a sites archaeological potential prior to submission of a planning application. PPS5 was short lived, but much of the guidance in PPS5 was adopted into the new National Planning Policy Framework in 2012.

The provision of developer funding for archaeology resulted in the development of numerous independent archaeological companies, and in recent years, the local authority based units have largely died out. Most companies nowadays are small, with tens of employees rather than hundreds, as well as numerous sole traders, particularly in the fields of specialist finds analysis. The fact that archaeology is developer funded also means that it is subject to competitive tendering to win projects, with the best price to fulfil the councils brief for the works usually being the winner. As such the whole process is very different to the preconceived notion of a cohort of academics and university students spending season after season studying every aspect of a single site in painstaking and minute detail. Furthermore, we can no longer choose where to go and what to dig up, rather, we are driven by the needs of our clients, so one week we may be excavating an Anglo-Saxon cemetery in Norfolk, then the next week Victorian tenements in Sunderland. Unfortunately, this also means we cannot, like academic research digs, restrict our digging to a few months in the summer, but have to be outdoors all year round, so a decent set of waterproofs and some woolly socks are a must!!

Hoeing snow at Sleaford Power Station

Because of the restrictions imposed by the nature of the industry, commercial archaeology can often seem a brutal process, with a lot of the heavy work undertaken by mechanical excavators, or a ‘big yellow trowel’ as they are colloquially known. That’s not to say there is not a lot of manual work after that. As soon as the topsoil is stripped off a site, its down to the mattocks, spades and shovels, and yes the trowels do still make an appearance as well. An experienced archaeologist can move a remarkable amount of soil with a trowel, and they have also been known to come in handy for cutting birthday cake in an emergency!!

In the 21st century, development led archaeology represents by far the majority of archaeological work undertaken in the UK, and the fact that this archaeological work is driven by the location of new developments, rather than a research focussed programme intended to test or prove a certain theory, has resulted in a new understanding of the country’s history and heritage, often leading to reappraisal and revision of traditional theories. The vast majority of the output of commercial archaeology is in the form of reports required by the planning authority, ‘grey literature’ as it is known, with only a minority of key sites reaching formal publication. However, numerous attempts have been made by academic researchers and commercial archaeologists alike in recent years to collate and interpret this ever growing body of data to further the understanding of the finite archaeological resource that lies beneath our feet.