Magna – Summer progress 2023

At the  start of July, the HLF funded project started at Magna. The £1.6M project was to support excavation and explore the impact of climate change, and awarded to the Vindolanda Trust.

The Teesside University team were involved in the installation of the weather station and monitoring system – VanWalt, which provides data every 15 minutes from a wide range of sensors including pH, temperature, ORP and moisture.

In July, soil monitoring was conducted by Dr Gillian Taylor and Dr Rhys Williams prior to the excavation. You can keep upto date with excavation progress by following the dig diary. The excavation in 2023 focuses on milecastle 46 and already some interesting artefacts such as a steelyard beam.

There is also a wonderful report in current archaeology about Magna and magnifying milecastle 46.

 

 

Climate change monitoring

One year has now past since Dr Gillian Taylor was involved in the installation of a weather station at Fort Magna. It is not just a weather station but also monitors ground chemistry to help us understand seasonal changes. The data has been fascinating and watch this space for updates on conference presentations later in the year..

https://www.vanwalt.com/projects/soil-research-equipment-for-the-vindolanda-trust/

Not content with one weather stations, in April 2023, the team also installed a similar system, provided by Van Walt across the Vindolanda site, monitoring more chemistry, more conditions and importantly watching those anaerobic areas very carefully, as we all know by now, the anaerobic conditions are important for the preservation of artefacts.

There are two other blogs posts, whom have written about the adventures of putting in the new system, so enjoy the link

https://www.vindolanda.com/blog/monitoring-the-buried-archaeology-of-vindolanda

https://www.vanwalt.com/dubois/2023/04/17/whisky-and-paracetamol-when-the-customer-assists-in-a-multi-sensor-network-installation/

https://www.vanwalt.com/dubois/2023/04/23/whisky-and-paracetamolepilogue/

New Output: Unique chemical parameters and microbial activity lead to increased archaeological preservation

Orr, C.H., Williams, R., Halldórsdóttir, H.H. et al. Unique chemical parameters and microbial activity lead to increased archaeological preservation at the Roman frontier site of Vindolanda, UK. Sci Rep 11, 15837 (2021). https://doi.org/10.1038/s41598-021-94853-7

Published: 04 August 2021

Abstract: Waterlogged burial conditions impact upon artefact preservation. One major determinant of preservation is presence and behaviour of microorganisms, however, unravelling the mechanisms, especially in waterlogged conditions is challenging. In this study, we analysed elemental composition, bacterial diversity and community structure from excavation trenches at the Roman Site of Vindolanda, Northumberland, UK, using pXRF and 16S rRNA gene amplicon sequencing. Excavation trenches provide information of different occupation periods. The results indicated that microbial communities were dominated by Firmicutes, Bacteroidetes and Proteobacteria at a phylum level. Samples which also had visible vivianite presence showed that there were marked increases in Methylophilus. Methylophilus might be associated with favourable preservation in these anaerobic conditions. More research is needed to clearly link the presence of Methylophilus with vivianite production. The study emphasises the need for further integration of chemical and microbiome approaches, especially in good preservation areas, to explore microbial and chemical degradation mechanisms.

Vivianite on Wood

This image shows the adherence of vivianite on wood recovered at Vindolanda.

Untreated wood normally degrades whilst buried due to rot and bacterial attack. The conditions at Vindolanda preserve wood exceptionally well. Vindolanda is known particularly well for its preservation of wooden tablets with handwritten correspondence. These adherence of vivianite into the wooden tablets seem to have helped preserve them over millennia of burial. TUBA is researching how vivianite adheres to wood, and how wood degrades at Vindolanda.

Vindolanda Site

This image shows part of the excavations currently underway at Vindolanda.

Vindolanda is a Roman military fort and World Heritage site settlement located along Hadrian’s Wall, the furthest North that the Romans ventured. Vindolanda is a World Heritage site known for its excellent preservation of materials that degrade quickly at other sites. Vindolanda houses an impressive leather shoe collection, and wooden tablets containing some of the oldest handwritten letters in the UK. These are preserved so well because of the environmental conditions at Vindolanda. TUBA is investigating these conditions and why material is preserved so well, to then apply these processes to other forensic and archaeological investigations.

Vivianite on Teeth

This image shows the adherence of vivianite to teeth, from a maxilla recovered at Vindolanda.

Vindolanda is known for its exceptional preservation of easily degradable material. Part of this is due to the formation of vivianite preserving material through a currently unknown function. The robusticity and nature of bone provides TUBA with material that can be manipulated extensively during the investigations of vivianite adherence and preservation at Vindolanda.

SEM Image of Vivianite

This image shows the crystalline structure of vivianite, captured using scanning electron microscopy (SEM).

Vivianite (Fe3(PO4)2·8H2O) is a mineral that forms in anoxic environments, or rather, waterlogged soils with poor oxygen levels and sources of iron and phosphate. The conditions at Vindolanda promote vivianite formation. Vivianite is colourless until exposure to oxygen, when it quickly becomes a pale blue colour. TUBA is investigating why vivianite is so effective at preserving material excavated at Vindolanda.