Archaeomagnetic Studies at the Bradford Kaims

Archmag

Sam Harris, Doctoral Research Student – University of Bradford

Firstly, it is purely coincidental that I study in Bradford (West Yorkshire) and am coming to take samples at the Bradford Kaims. As an archaeomagnetist, and we are pretty few and far between, it is always amazing the variety of sites that you get to see and work on. Having parachuted into the Bradford Kaims trenches for the second time, this site is no exception in its wonder. Placed at the edge of a fen, the variety of soil and sediment types on site is impressive! This offers the perfect opportunity for archaeomagnetic studies.

For those that aren’t quite sure what this odd science (magic) is, you are welcome to peruse my website, which is listed at the end of this blog post, for some answers. Simply put, the Earth has a magnetic field which varies over space and time. A record of the past geomagnetic field can be found in the in situ remains of hearths, furnaces, or other anthropogenically fired features that we as archaeologist excavate on a regular basis. Archaeomagnetic studies seek to improve our knowledge of past geomagnetic field changes through the analysis of this material. Why though, I hear you ask…

This is because we can use the knowledge of geomagnetic fluctuations over time to conduct archaeomagnetic dating and gain an idea of the last time that some fired archaeological features were heated. Having a dating method which directly relates to an anthropogenic activity, rather than to the end of an organism’s carbon absorption for example, is a powerful tool for the archaeologist.

Archaeomagnetic dating was first attempted at the Bradford Kaims in 2011. While the study was successful and the date recovered for a fired hearth feature in Trench 6 (c.4350 cal.BC) was considered accurate given other artefactual dating evidence for the site, newly acquired radiocarbon dating evidence suggests that the calibration methods used for the archaeomagnetic dates produced erroneous results. This was due to the use of an experimental and alternative calibration model from outside the UK, as the current UK calibration model does not stretch back into the Bronze Age or before. This previous study, and others since, have identified the need for further work to be undertaken. This is where me and my PhD come in! My main aim is to improve our understanding of geomagnetic field change during prehistoric periods, but particularly the Neolithic.

At the Bradford Kaims this season, I sampled two features associated with the Bronze Age burnt mounds, both of them interpreted as fire pits containing fired stones, burnt sediments, ash, and charcoal. These features will provide good radiocarbon dating records, alongside the archaeomagnetic signatures for the fired subsoils within and below them.

Thanks to the Bamburgh Research Project’s excellent radiocarbon dating programme at the Bradford Kaims, the fired archaeological features that I can archaeomagnetically study will have independent dates associated with them. By building up a number of well-dated features in this way, a new calibration curve for the UK can be created, with the Bradford Kaims being a central case study in this process. Through the combined use of radiocarbon dating and archaeomagnetic dating on prehistoric sites like the Bradford Kaims, we can gain a more nuanced understanding of their chronologies.

Sam’s website can be viewed at; www.neolithicarchaeomagnetism.weebly.com

Sam’s Twitter can be viewed at; @Archaeomagnetic

Visit to the Heugh Excavation on Lindisfarne

We recently visited the ongoing excavation on Lindisfarne that is being undertaken by the Archaeological Practice as part of the Peregrini Lindisfarne Landscape Project. It’s a fascinating site and should be familiar to some, as it has been the subject of a number of news reports. The team have opened up a series of trenches on the Heugh, which is the long, narrow, dolerite rock promontory above and to the south of the medieval priory site in Lindisfarne Village. The Heugh has long been speculated to have been part of the early medieval monastery founded around 634 during the reign of King Oswald, as a daughter house of Iona. It quickly rose to be a site of great importance and remains famous for its association with Saint Aidan and Saint Cuthbert as well as being the place where the wonderful Lindisfarne Gospels were made.

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The foundations of the potential new church on the Heugh

Here the excavation team have found the almost complete foundation of a stone building, that all current evidence suggests is early medieval in date. Direct dating evidence is scant, but the near complete absence of later medieval and modern pottery from the structure, despite a considerable volume of material being excavated, suggests a time of construction when pottery was not in use. This, together with the absence of mortar bonding and the rather crude-tooled finish to the stones, adds up to a quite compelling argument that they have discovered a building from the early monastery. In addition, the ground plan, with what appear to be a chancel and nave, is very suggestive of a church which greatly adds to the excitement.

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The finish of the stones is mostly quite crude and no mortar bonds them together. It was a substantial structure though with wide foundations made of large blocks.

We know from textual evidence, particularly the writings of Bede, that Aidan’s successor Finan built a timber church that was later covered in lead. We also know from a later text that this church was removed to Norham as a relic when the monastery was partly abandoned in the 9th century. We can be certain then that this structure is not that church, but the site would have likely held several churches during its lifetime. The crude working of the stones, particularly of some sculpted stones that appear to form a trough or bowl, and part of a possible window, are very interesting as they may suggest builders that are beginning to come to terms with a new construction medium- stone instead of wood. As a consequence it is tempting to imagine this building as particularly early, but it is perhaps also possible that it could be later. In the Viking age many monasteries were abandoned, but the continued use of stone in the construction of monuments at Lindisfarne suggests that the site remained important, though the sculpted fragments of the 10th century and later often appear to be cruder and derivative. It is therefore possible that this structure could date from this later time, when the working of stone was not done with the same confidence or competence as the 8th and 9th centuries.

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Bamburgh Castle, Lindisfarne’s near neighbour, just 8.5km over the water!

It is tempting also to see the location on the height of the Heugh as meaning that the building was meant to be seen from a distance. It has a clear sight line to Bamburgh, the great secular palace site, and this may be no coincidence. We have evidence of pre-conquest stone architecture at Bamburgh and it is likely that the use of this medium was intended in both instances to reference Rome. In the case of a monastery, this would be the Catholic Church as the successor of Rome, and at the palace as legitimising rule through being the heirs of the Romans. This is a good lesson in why it’s important to study how a site fits into its wider world in order to properly understand it.

Bamburgh Castle, Trench 3 – Hope Taylor nearly in reach!

As the level of Brian Hope Taylor’s 1974 excavations gets tantalisingly close, Trench 3 staff continue the process of gradually joining our excavations to his.

 

 

This is achieved through the removal of features and contexts which are stratigraphically higher in sequence including a stone wall (possibly 9th Century) last week, underneath which a number of finds were discovered. Our progress is described in the video below.

 

 

New article on our excavations at Bamburgh Castle

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The windmill office in the West Ward, between our two excavation trenches

Archaeology, the magazine of the Archaeological Institute of American has published an article on our excavation work at Bamburgh Castle. It is available online here:

Stronghold of the Kings of the North

 

The King in the North – a talk

The Friends of St Aidan’s Church, Bamburgh have organised a talk by Max Adams on his biography of St Oswald. It is at St Aidan’s at 4:00 pm Sunday 24th April. Entrance if £5.00 and includes afternoon tea.

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Writing a biography of an early medieval king is a challenge, so succeeding in writing an acclaimed one, as Max has, suggests we will be in for a treat. Do make it along if you get the chance.

Thanks for a great season and a special video

It is hard to believe that another season is behind us, yet here we are looking back on amazing times and wonderful discoveries. I would like to thank all those who came along and helped make the season such a success. Thanks to you, our readers, for staying tuned to the blog. Thanks to all of our diggers, the Bamburgh Castle staff, the Brown and Barber families, who hosted us at the Kaims, and all those in Belford who made us feel most welcome. A special thanks, though, must go to our hard working staff, whose constant effort, in all conditions made everything we achieved possible.

Graeme Young, Project Director

As a perfect end to the season our trench three supervisor, Anne Hartog, made one last discovery…

Our end of season lecture is available to view online

Our wrap-up lecture was a great success! We had nearly 40 members of the community, students, and staff members attend. We started the evening with Director Graeme Young discussing our Bamburgh Castle trenches followed by a short explanation of 3-d model rendering and photogrammetry by Outreach Officer Cole Kelly. Finds Supervisor Jeff Aldrich gave us an overview of the small finds from the castle and Director Paul Gething wrapped up the evening talking about our Bradford Kaims site. A big thanks goes out to Phyl Carruthers for coordinating space for our lectures at the beautiful Bell View center in Belford.

Or watch the lecture on youtube.

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Beautiful floor surface in trench one

While half-sectioning what we thought was a large pit feature we uncovered part of a highly organized stone floor surface. It would be extreme to call it mosaic, but the stones are small and arranged carefully. Floor surfaces such as this are not uncommon in the later medieval deposits in trench 1, but we have never run across one associated with an anglo-saxon context.

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Since then we have uncovered more of the floor and sampled the soil above for dating evidence, such as seeds and bone. The surface is cut by several small pits and post holes, which although damaging to our floor surface can provide a better understanding of the stratigraphy of the site.

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Harry and Chris working in trench one

Our 2014 Season Wrap-up Lecture

Please come join us for the final lecture of the season. We will be talking about all the exciting discoveries of this season. If you can’t make it out, don’t worry. We will film the event and put it on our youtube channel. Hope to see you there!

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Free Public Lectures in Belford this Season

This summer during our excavation, which begins 2nd of June and continues to 27th July 2014, we are again going to arrange weekly evening lectures. They will be available free to students and members of the public, but if anyone attending wishes to donate a little towards the venue cost, it will be gratefully received.

The venue is at the Bell View Centre, 33 West Street, Belford, Northumberland, NE70 7QB

Lectures will be at 7:00 pm each Tuesday evening.

The list of the first seven lectures should be below. We will probably arrange a summary of the season’s results during our final week, which begins 21st July.

The Heart of the Fortress, Archaeology of the Inner Ward at Bamburgh Castle.  Graeme Young, 3/6/14

The Burnt Mound Misconception (Part 1): Excavation Strategy.  Tom Gardner,  10/6/14

Flodden 500, Archaeological Investigations of the Battle of Flodden. Chris Burgess,  17/6/14

Bradford Kaims Prehistoric Landscape Project.   Paul Gething,  24/6/14

The Burnt Mound Misconception (Part 2): Environmental Strategy. Tom Gardner,  1/7/14

The Art and Material Culture of Northumbria.   Stephanie Chapman,  8/7/14

The Anglo-Saxon Earls of Northumbria.  Graeme Young,  15/7/14