Bay Of Firth

HY 387 141 (centred on) This is a project looking at former relative sea level change and prehistoric settlement around Orkney. Since 2006 a programme of coring has taken place and two radiocarbon dates have been obtained which indicate that the sea only reached present levels around the archipelago c4000 years ago. This means that for much of the period of human settlement in Orkney the islands were bigger, but subject to rising sea levels.

Work from 5–11 June 2009 focused on the possibility that remains from earlier settlement (Neolithic or Mesolithic) might survive on the sea bed. Work centred on the Bay of Firth in order to follow up ethno-archaeological accounts of remains in the bay, which had been given support by the results of side scan survey carried out in 2008. More detailed geophysical survey work was also undertaken around the island of Damsay. In addition, eight potential targets were examined by divers, and five general dive-searches

undertaken.

Stone remains were recorded at five locations on the seabed. One comprises a stone pier, visible at low tide. The other four cannot be identified due to poor visibility and lack of resources. Vertical and horizontal slabs, coursed stonework, collapsed stonework, and upright features were all observed at depths that varied from 2–9m. Further work is planned.

Archive: With contributors, copies to be distributed to RCAHMS, Orkney SMR and ADS

Funder: The work in the Bay of Firth was funded by NGS/Waitt Grant. The project in general has received support from Historic Scotland, The Crown Estate, Orkney Islands Council, Scapa Flow Landscape Project

CR Wickham-Jones, S Dawson and R Bates – University of Aberdeen/University of Dundee/University of St Andrews

HY 387 141 (centred on) Work on Holocene sea level change

in Orkney indicates that relative sea levels only reached their

present position some 4000 years ago. This project which

was set up in 2005 aims to:

• construct a sea level curve to provide detail of former

changes in relative sea level around Orkney

• investigate the possibility that remains of past human

settlement might be preserved on the seabed

Work in March 2010 focused on remote sensing and

intertidal survey in the Bay of Firth. The validation of

potential submerged structures by diving has proved difficult

due to dense kelp growth and the problems of distinguishing

between local bedrock and collapsed structural material.

A number of shoreline structures are now being recorded

in order to understand the impact of marine erosion and

collapse. Further cores have been taken at Mill Bay, Hoy

and Dam of Hoxa, South Ronaldsay in order to broaden

information on past Holocene relative sea level changes.

Archive: With contributors, copies to be distributed to ADS, Orkney

SMR and RCAHMS

Funder: Historic Scotland, The Crown

HY 387 141 and HY 294 131 (centred on) Work on Holocene sea level change in Orkney indicates that relative sea levels only reached their present position some 4000 years ago. This project which was set up in 2005 aims to: construct a sea level curve to provide detail of former changes in relative sea level around Orkney; investigate the possibility that remains of past human settlement might be preserved on the seabed.

The project combines different strands of work including sediment coring, remote sensing, seismic survey, diving, intertidal survey, palaeoenvironmental analysis on land, in the intertidal zone and from submerged surfaces, aerial photography, archive searches, and ethnoarchaeology.

In April 2012 – March 2013 work focused on coring and diving in the Bay of Firth with the following aims: Investigation of the Main Mound site in order to determine possible anthropogenic origin; trial of subsea vibrocore equipment in palaeo-landscape and archaeological contexts; recovery of detail relating to organic sediments below the present seabed, indicative of a lake prior to inundation by the sea; reconstruction of Early Holocene inundation sequence as it took place in the Bay of Firth and production of palaeogeographic reconstruction as inundation took place.

Preliminary results indicate that the Main Mound is natural in origin. Work in 2014–5 will focus on the recovery of short sediment cores from around the mound in order to ascertain whether any evidence such as charcoal or micro-artefacts exist, suggesting the possible human use of this prominent place in the ancient landscape.

Trials of the vibrocore equipment were successful and further work will be undertaken in 2014–5. Lake bed deposits rich in mollusc remains exist beneath the marine sands recording the flooding of the basin following sea level rise. The combination of the high resolution seismic and dated cores allows a more comprehensive framework for inundation of this part of the Bay of Firth. As we are now able to provide a dated framework for inundation in this part of the bay, current modelling of the inundation process should add further insight to the exact timing and mechanism of inundation.

Brief dives were made at Loch of Stenness on one of the anomalies identified in 2011, a long mound to the N of the Seatter embayment, to undertake a visual inspection. Results support the seismic report from 2012 in suggesting that the feature may be artificial in origin.

Archive: ADS, Orkney HER and RCAHMS (intended)

Funder: Historic Scotland and Carnegie Trust

CR Wickham-Jones, University of Aberdeen

S Dawson, University of Dundee

R Bates, University of St Andrews

M Bates, University of Wales Trinity Saint David

D Huws, University of Bangor

N Nayling, 2013

(Source: DES)

HY 387 141 and HY 294 131 (centred on) Work on Holocene sea level change in Orkney indicates that relative sea levels only reached their present position some 4000 years ago. This project which was set up in 2005 aims to:

construct a sea level curve to provide detail of former changes in relative sea level around Orkney

investigate the possibility that remains of past human settlement might be preserved on the seabed.

The project combines different strands of work including sediment coring, remote sensing, seismic survey, diving, intertidal survey, palaeoenvironmental analysis on land, in the intertidal zone and from submerged surfaces, aerial photography, archive searches, and ethnoarchaeology.

In March – December 2012 work focused on coring in the Bay of Firth with the aim of investigating organic deposits below the present seabed, perhaps indicative of a lake or lagoon prior to inundation by the sea. Preliminary analysis of the core sediments shows a clear transgression, evident in both microfossils and molluscs, from fresh water to saline. Particle size suggests a lower energy environment after inundation. Dates from this core should help to identify the date of inundation.

In the Loch of Stenness a number of anomalies were identified in 2011, in particular a long mound to the N of the Seatter embayment, and an annular feature offshore to the S of the Ring of Brodgar. Seismic survey was undertaken across these anomalies and suggested that they may be anthropogenic (archaeological) in origin. Other work focused on modelling the pre-submerged landscape of Orkney and this will continue in 2013.

Archive: Contributors (currently)

Funder: Historic Scotland, Society of Antiquaries of London, Royal Archaeological Institute and Leverhulme Trust

CR Wickham-Jones, University of Aberdeen

S Dawson, University of Dundee

R Bates, University of St Andrews

M Bates, University of Wales Trinity Saint David

D Huws, University of Bangor

2012

HY 387 141, HY 425 660 and HY 294 131 (centred on) Work on Holocene sea level change in Orkney indicates that relative sea levels reached their present position some 4000 years ago. This project, which was set up in 2005, aims to construct a sea level curve to provide detail of former changes in relative sea level around Orkney and to investigate the possibility that remains of past human settlement might be preserved on the seabed.

The project combines different strands of work including sediment coring, remote sensing, seismic survey, diving, intertidal survey, palaeoenvironmental analysis on land, in the intertidal zone and from submerged surfaces, aerial photography, archive searches, and ethnoarchaeology. The work undertaken January – December 2014 focused on three areas.

In the Bay of Firth work focused on coring with the following aims: recovery of organic sediments from the western reaches of the Bay; recovery of organic material in the vicinity of the Main Mound site in order to determine possible anthropogenic activity; reconstruction of Early Holocene inundation sequence as it took place in the Bay of Firth and production of palaeogeographic reconstruction as inundation took place.

The use of vibrocore equipment and a small raft facilitated the recovery of sediment cores from the ancient lakebed lying towards the W end of the Bay. Core recovery was good with little deformation, and lithology and other analyses are taking place to build a picture of the inundation sequence. Recovery of cores in the vicinity of the Main Mound was not possible due to adverse weather but further attempts will be made to

complete this work.

In the Loch of Stenness work focused on coring with the following aims: recovery of organic sediments from key locations across the loch as determined by onshore archaeology and sonar and seismic scans taken in previous years; reconstruction of Early Holocene inundation sequence as it took place across the loch and production of palaeogeographic

reconstruction as inundation took place.

The use of vibrocore equipment allowed the extraction of eight cores from the S half of the loch. Research is ongoing but preliminary work by Killingbeck has reconstructed a detailed sequence of inundation and palaeoenvironmental change, suggesting that present sea level was not reached until at least 3000 BP.

The work in Sanday aimed to extend research away from the heartland of Mainland Orkney and to gather, date and interpret the palaeoenvironmental record from marine and intertidal sediment cores from key sites outwith the World Heritage area but near onshore heritage sites of international importance.

Preliminary work was undertaken including walkover survey for source sites where palaeoenvironmental cores might be obtained and some trial auguring.

Archive: Contributors (currently), ADS, Orkney SMR and RCAHMS

(intended)

Funder: Historic Scotland

CR Wickham-Jones, S Dawson, R Bates, M Bates, D Huws, E Gal and J Killingbeck – University of Aberdeen, University of Dundee, University of St Andrews, University of Wales, Trinity St David and University of Bangor

(Source: DES)