The life of a post-hole

with Kim Darmark

Anl_211

Digging post-holes can be rather tedious, non-rewarding work. Cut through, photograph, document the section, take samples and on to the next one. To a certain extent, this has been true at Kvarnbo as well, but a surprising number of the post-hole remains have, on the contrary, been challenging and exciting to investigate. This is due partly to the fact that so many of them have a life history which is possible to reconstruct. It is often possible to follow the events that have taken place through the different constructional elements making up the feature. In quite a few cases, it is possible to see the edges of the original pit, filled with a lighter primary fill, which was deposited in the pit at the moment of its construction. This fill is often lined with stones, creating a solid base for a beam to rest on. Both naturally rounded stones from the surrounding and rugged, fire-cracked blocks of stone have been chosen for this purpose. The primary fill contrasts markedly from a darker secondary fill, which enters into the pit at a considerably later date, when the old supporting beam is removed from the pit. The darkening of the fill represents many years of intensive use of the site, during which large amounts of organic remains have been tossed on site, creating refuse layers, usually referred to as cultural layers. This dark soil only infills the small chamber that is produced by the stones in the stone packing, and is often also rich in finds, which constitutes the other interesting aspect of post-hole investigation at Kvarnbo. Since we sift the soil through sieving net using water, we find every little find, even tiny ribs, scales and vertebrae from fish, which has ended up in the post-hole. The usual finds are bones and pottery, but a few less common items have been found as well, such as pearls, and small copper loops. Almost every feature that has been investigated this season has contained at least a few finds, some of them large amounts, and gives testimony to the richness of the cultural layer once present at the site.

Press this link to see the 3D model of feature 211 during investigation 😉

Reflections of a volunteer – part 5

by Kåre Lund

Kåre

Kåre at the sieving station, at which he found a really exquisite bead that looks black, but actually has the colour of an aubergine 🙂

My name is Kåre, and I had the pleasure of being a volunteer at the Kvarnbo Hall dig site. My background is not from archeology, but as a teacher in Norway.

I first heard about this project during a convention in Mariehamn, Åland, last year, where Kristin talked about the project and the local islands during the Viking age. I`ve always been interested in history, so when she informed about the possibility to volunteer, I thought this might be an interesting experience.

The excavation had already been going on for a few weeks before I arrived, but I was given a good introduction to the basic tools of the trade (trowel, bucket, hand shovel, measuring tape), and shown where and how to dig a proper hole in the ground, and how to wash, sift and sort the soil. It was also a new and interesting experience to learn what to look for. Especially, the fact that you could taste things, to feel the texture and hardness against your teeth. I haven’t put this many rocks in my mouth since kindergarten. Usually, I have to tell pupils in first grade not to put things from the ground in their mouth 🙂 To see and experience how much work that lies behind finding and sorting objects in the ground was an eye opener.

It was also very nice to work with the people who share a lot of the same interests. I don`t always get the opportunity to do this, since teachers are a very diverse group. I also found the tasks I was given interesting when I was told why it was done. Talking to, learning new things and getting to know the other people at the site made the work even more rewarding. I learned quite a lot from all of this.

The thing I found I had to work most with was to overcome my feeling of inexperience in the field, and my “Oh God, I`m going to destroy something if I do this wrong” – reflex. I think this made me a little hesitant at first, until I got my feet wet. Despite my inexperience in the field I felt I was included among the others at the site and made to feel welcome among everyone.

All in all I`m happy I volunteered for this, and hope to do it again sometime.

Traditional Strategy and New Techniques

by Frands Herschend

Strip (off the plough soil), map (the patterns you see) and sample (material from mapped structures) – is an archaeological field strategy applied to settlement remains in agricultural land, where crops have been growing for centuries. Ultimately, the method has become prolific, because of the gradual shift in the use of the cultural landscape. This shift made arable land more important and organized not least by means of roads. Consequently, farms were moved out of the farmland when possible. In Iron Age, on the other hand, arable land was less important, while grassland and meadows contributed substantially to subsistence. Not surprisingly, a rational Iron Age farm situation was in the centre of the farm’s agricultural area. Few roads were needed.

In Kvarnbo, change has been model, and today, the farms at Johannisberg are situated next to and above the arable land in which the Iron Age Kvarnbo hall stood on its small drained hillock.

When the excavations were planned, the strip, map and sample method was the obvious choice. But there are different way of stripping, mapping and sampling, and at Kvarnbo we have introduced a new mapping method in order to develop the general method. The testbed was successful during the test excavations in 2014, and in 2016, this mapping method was developed to become a routine.

Except for a handful of GPS reference points defining some of the test pits before the excavations started (see here), nine main reference points were defined after the top soil was stripped off in the area of over 1000 m2, and complemented with 183 reference points inside of that area. Supported by these, all (georeferenced) exact measurements, plans and sections are based on photographic 3D models. Also, a large scale plan was made with a drone during a 10 minute photo session and its orthographic projection, printed as an overview, has enabled the team to orientate itself on the site.

New techniques

Archaeological documentation goes hand in hand with interpretation. Description dominate fieldwork without excluding interpretation, and in the field, ocular observation is the general mode of perception: either you see something of you don’t. Later on, during the report writing process, interpretation and lab results dominate in order to answer the question: what cultural phenomena have we excavated? The problem in field archaeology is not what one observes, the problem is that which cannot be seen.

Overlapping features in the trench of 2014

In this section from the trial excavations of 2014, one can see archaeological features from Late Iron Age (A12 and A13) been transected by more modern plough furrow (A18).

For instance, looking at plough layer and plough furrows or any other depression, the point is to describe some sort of “ploughing biography” of the field as a part of the its involvement in history. It is easy to see the dark furrows when they cut into the yellow underground, but difficult to detect them at the bottom of the plough layer, and impossible higher up, although they may well exist in soil 20 centimeters or more below the surface. In fact, only by means of close observation of soil sections can one distinguish between ploughed and not ploughed soil.

Since we want to sample the contents of the different fills in postholes, we make a preliminary section of the first centimeters of the soil until, based on this section, we can dig away the plough soil, that is, the contamination of the prehistoric fill. As a result, we can, for example, conclude that the burnt clay, which represents burnt walls and was abound in the test pits, doesn’t exist in the postholes of the hall (because it was never burnt down).

So far, we have sectioned, described and interpreted c. 230 features of 273 on the c. 1000 m2 of our site. This is time consuming, but the ensuing 3D documentation is fast. On average, therefore, a team of four professional archaeologists and 2-3 amateurs can section, describe, interpret, sift and model 20-25 features per day, and sample soil for chemical and macrofossil analyses. 3D-modelling brings a new better and cheaper standard to strip, map and sample methods.

 

Reflections of a volunteer – part 4

by Peter Kollin

The blacksmith Peter with his leather hat :)

The blacksmith Peter with his leather hat 🙂

I live in Sweden and I’m a blacksmith, but I also have a Bachelor’s degree in archaeology. I use to attend the annual Viking market in Kvarnbo, Saltvik, and during the market last year I learned from a friend about the upcoming investigations at the Kvarnbo hall site. I got in touch with Kristin and made arrangements for the accommodation, so that I could participate as a volunteer.

I spent four weeks at the excavation. It was a fantastic experience and I’ve met so many nice people and made new friends during the time spent on Åland. The archaeologists in the crew were all highly skilled and very generous with sharing their knowledge. I have participated in a number of excavations before, but this one was by far the one that gave me most in terms of experience and knowledge. The one thing I had never done before, but got to work with in Kvarnbo, was to assist in the process of stripping of the plough soil with an excavator. It was really exciting to work next to the excavator, cleaning up after the machine, and watching the archaeological features appear. This is really what makes archaeology – to see the traces of more than thousand years’ old houses, hearths and cooking pits emerge in front of your eyes. After the soil stripping, there was a massive effort put into cleaning the entire surface of the 1000 m2 large trench using just trowels. This made the archaeological features uncovered with the help of the machine even more visible and many more new features were discovered. The investigation of every single feature followed. Unfortunately, I only had the time to investigate a few, as I had to leave before the end of the investigation… One of my personal best finds was a nice segmented blue glass bead with parallels to a find in Birka´s black earth.

I will always carry in my heart the warmth of all the people I met at the investigation and all the good laughter we shared and I wish you all good luck with the rest of the investigation. I really hope there will be further investigations at this exciting site so that I can participate once again. I also want to thank Saltvik B&B for a very nice accommodation and treatment. Last but not least, many thanks to Kristin Ilves who made it all happen!

A real visitors’ day!

Today was the day of a grant feast in Viking style in the Kvarnbo Viking village that was launched by Ömsen together with Fornföreningen Fibula to celebrate Ömsen’s 150 years of activity. And what a feast it was! 🙂 Good food and excellent ale, many wonderful and happy people. At the site, we were also prepeared for the visitors – I even created an “extra” trench marking out all of our 252 archaeological features so that we could explain everything without stepping into the real trench. We were happy to see that our project sparks interest in a lot of people 🙂 – many found their way from the Kvarnbo Viking village to us and there were lot of questions asked. It is stimulating and encouraging to meet so many enthusiastic visitors and we thank everybody that found their way to our site!

Trench on the paper

Post-holes

One by one, archaeological features at the Kvarnbo Hall site, mainly post-holes, are being investigated. And there is a number of really pretty ones among these post-holes – several are preserved much better than I expected (about 0,4 m in depth), and every so often, there is a stone packing evident. In at least three cases so far we have post-holes that have been filled with the material from a hearth and thereby filled with finds of bones from many different creatures (including fishes and birds) as well as pieces of pottery. Every  post-hole not yet investigated is therefore like an unopened package, whose contents are still unknown and it is up to us to unwrap the mystery 😀

Post-holes