Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 – 2012-13

  • View
    215

  • Download
    0

Embed Size (px)

Text of Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 – 2012-13

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    1/117

    WA Coastal & Marine

    April 2013Ref: 79441.02

    Outer Hebrides Coastal Community MarineArchaeology Pilot Project

    Year 2 Report

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    2/117

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PILOT PROJECT

    REPORTYEAR 2(2012-13)

    Prepared by:

    WA Coastal & Marine7-9 North St. David Street

    EdinburghEH2 1AW

    Prepared for:

    Historic ScotlandLongmore HouseSalisbury Place

    EdinburghEH9 1SH

    Ref: 79441.02

    Apri l 2013

    Wessex Archaeology Limited 2013

    Registered Scottish Charity No. SC042630 and in England and Wales, No. 287786.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    3/117

    OHCCMAPP2012-13 Report

    i

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PILOT PROJECT

    REPORTYEAR 2(2012-13)

    79441.02

    Title: OHCCMAPP: Report Year 2Principal Author(s): Dr Andrew Bicket, Dr Simon DavidsonManaged by: Dr J onathan BenjaminOrigination date: J uly 2012Date of last revision: April 2013

    Version: 02Wessex Archaeology QA: J BStatus: FinalSummary of changes: Minor edits to contentAssociated reports: 79440.02Approval: Philip Robertson (Historic Scotland)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    4/117

    OHCCMAPP2012-13 Report

    ii

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PILOT PROJECT

    REPORTYEAR 2(2012-13)

    79441.02

    Summary

    This report summarises the OHCCMAPP activity undertaken during the 2012 summer fieldcampaign and subsequent analysis during the autumn and winter 2012-13. Following on from

    the baseline data gathering, initial outreach and fieldwork of Year 1, some of the mostpromising leads were followed up during Year 2. Incorporating the three themes developed inYear 1:

    x Marine Resource Explo itation;x Maritime History and Transport; and,x Submerged Prehistory Potential.

    Field InvestigationsSix locations were investigated across South Uist, Grimsay, Harris, and Lewis, a total of 39coastal and intertidal structures were recorded (Appendix I); the majority were previouslyunrecorded and requiring specialist field investigation and recording.

    In collaboration with RCAHMS, field recording of prehistoric and historic sites wasundertaken at Stulaigh and Hartavagh, South Uist, accessible only by boat. The sites wereinvestigated as a direct consequence of the outreach campaign undertaken in 2011 when thefield team met J .J . McDonald of north Locheynort.

    Diving and snorkelling surveys were carried out at all sites except Stulaigh. At Locheynort,Grimsay and Harris, underwater surveys and local outreach were aimed at prospecting forand locating unrecorded structures and wrecks in the area. A number of yairs andcauseways were located in the lower range of the intertidal zone, which were previouslyunrecorded. Reports of wrecks were received but ground trothing was not logistically feasibleas they were located in open water.

    Underwater survey was undertaken at Lundale, Lewis on the fringes of Loch Roag. Theinundated bog has substantial in situ remains of previous wooded land surfaces which havesubsequently been inundated by blanket bog, and then by sea level rise. Peat was alsorecovered and dated at Hartavagh, South Uist. Remnants of Late Pleistocene peat depositswere recovered in the intertidal zone at Hartavagh indicating that palaeoenvironmentalresources of significant age are present and well-preserved in the intertidal zone; in additionto mid-Holocene peats known from beaches and other submerged locations in the regions(e.g. Ritchie 1985). This provides scope for improving relative sea level models in the regionand developing baselines relating to palaeogeography and early prehistory.

    A bespoke outreach activity was undertaken with the Seafishing community at Stornoway,

    Lewis to present the project and to gain an insight into the types of marine and maritimearchaeology information accumulated by this group (Appendix IV). Considerable knowledge

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    5/117

    OHCCMAPP2012-13 Report

    iii

    of the marine environment with relevance to cultural heritage exists, requiring a dedicatedresearch effort.

    Whilst OHCCMAPP was being undertaken additional reports of material were made from

    outside the core study areas. With the project logistics in place it was possible to expand theresources and specialist staff to examine these reports in more detail. Significant earlyMesolithic material was recovered from above, and below the waterline at Lub Dubh-Aird,Upper Loch Torridon following on from a community report and led by Prof. Karen Hardy. Ahistoric wreck from Loch Laxford, West Sutherland was also reported to the project and willbe examined as part of the SAMPHIRE (Scotlands Atlantic Maritime Past: HeritageInvestigation Research & Education) project, beginning 2013.

    By undertaking the pilot project it is clear that investigating the full-spectrum of the coastalzone is challenging but substantial resources exist for the investigation of marine resourceexploitation. A very large resource of stone-built yairs and causeways are under-reported if atall from the study areas considered in OHCCMAPP, a key element to understanding the

    economy and subsistence strategy of post-medieval townships. The intertidal zone as awhole, changing across prehistory is also a key area of focus for investigating marineresource exploitation, but also submerged prehistory potential in the islands. Modelling hasindicated that for at least the Neolithic and Mesolithic, the contemporary coastlines are nowlargely underwater or fully submerged. For example the remains at Northton, Harris may bethe last remaining element of more extensive site or sites that have been inundated anderoded during the later Holocene.

    Palaeogeography modellingHigh-resolution LiDAR and multibeam bathymetry datasets were obtained for the Sound ofHarris and northwest Lewis coast (including East Loch Roag). A series ofpalaeogeographical models have been produced, in lieu of sub-bottom geophysical surveys,which provide a means of prospecting for areas of submerged prehistoric potential. This ismost valuable in the Sound of Harris where the topography seamlessly overlaps the moderncoast. The Lewis multibeam datasets are located too far offshore to constrain current relativesea level models. Typically other geophysical survey datasets are of limited cultural heritageuse as they of too coarse resolution or distance from the coast.

    By undertaking palaeogeographical modelling using freely-available datasets from the Soundof Harris the three themes of OHCCMAPP have been brought together for a number ofprehistoric and historic scenarios including the Mesolithic, Early and Late Neolithic, BronzeAge, Iron Age with an additional Viking scenario. The development of the Sound of Harris asa largely terrestrial and intertidal landscape during the Mesolithic with a major seaway linking

    the Minch to the Atlantic along the Harris coastline provides an important parameter forconsidering the colonisation and exploitation of the Outer Hebrides from the earliestprehistory in the Islands. Events such as the breaching of Lake Agassiz within the context ofglobal sea level change may have led to an inundation of coastal land but also an increase inthe area of the intertidal zone as well as water-borne access into the landscape which mayhave benefitted early prehistoric groups.

    A major seaway by the Neolithic, the Sound of Harris lies at the edge of the prehistoric worldbut was linked to the wider maritime landscape (Garrow and Sturt 2011) and increasinglyinhabited and developed by later prehistoric people. Potential exists within shelteredembayments and complex coastline configurations around the Sound of Harris for in situpalaeoenvironmental and perhaps archaeological remains from c. 7000 BC until at least the

    Bronze Age, and probably Iron Age (Appendix III).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    6/117

    OHCCMAPP2012-13 Report

    iv

    RecommendationsBy incorporating all the disparate elements from OHCCMAPP it is clear that multi-disciplinaryworking incorporating specialists above, at and below the water line provides the means toinvestigate the highly localised archaeological, geoarchaeological and historical remains that

    a given location might contain. Especially in remote locations, where the opportunity todeploy survey teams is rare or increasingly costly, a full-spectrum multidisciplinary teamrepresents a cost-effective deployment.

    The logistical support provided by a small but reliable research vessel is a key but potentiallyexpensive factor. Providing access to mainland and smaller island coasts and a platform formounting or supporting diver, geotechnical and geophysical surveys, a support vesselfacilitates a greater range of data-gathering. During OHCCMAPP field campaign, vesselsupport was provided by community members including local fishermen and fish farms. It isrecommended that consideration of gaining access for archaeological and cultural heritagepurposes during the downtime of publicly owned small craft or research grade vessels,maintained by institutions such as Marine Scotland, the BGS and others would provide a

    cost-effective means of expanding the capability of cultural heritage in the coastal and marineenvironment in Scotland. Incorporating a cultural heritage specification into the surveyparameters of these vessels would also be beneficial for maximising the resolution andcoverage of publically owned (or financed) geophysical data into areas of cultural heritageinterest.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    7/117

    OHCCMAPP2012-13 Report

    v

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PILOT PROJECT

    REPORTYEAR 2(2012-13)

    79441.02

    Acknowledgements

    The support of various members of the communities of Grimsay, Locheynort, Stornoway,Manish and Lochboisdale greatly aided the project team in the field. Marine Harvest atLochboisdale is thanked for logistical support and transport to and from Hartavagh. J J

    McDonald is thanked for sharing his knowledge of the marine environment and transport toand from Stulaigh. His brother Alexander McDonald is thanked for assisting the dive team inLocheynort. Mairi Stewart is thanked for supporting the team at Grimsay. Dr Rob Lenfert isthanked for his time and expertise during the diving surveys.

    Prof Karen Hardy and Dr Torben Bjarke Ballin are thanked for supporting the work at LubDubh-Aird. Andrew Patrick is thanked for taking the time to examine the coast in detail, foruncovering a complex and rich archaeological site. Andrew and Carol are thanked for theirfield support in Upper Loch Torridon.

    Philip Robertson and Rod McCullough at Historic Scotland are thanked for supporting theradiocarbon dating assay and geophysical analyses and the project in general.

    All those who reported finds, sites and stories to OHCCMAPP are warmly thanked forproviding a wealth of information. It was not possible to investigate every lead within the pilotproject; we thank you for your time and knowledge.

    Data Licences

    NOT TO BE USED FOR NAVIGATION

    Crown Copyright and/or database rights. Reproduced by permission of the Controller ofHer Majestys Stationery Office and the UK Hydrographic Office (www.ukho.gov.uk)(Appendix II, III, p50, p52, p55, p55, p56, p57, p60).Contains Garmin BlueChart data 2013.

    Contains Ordnance Survey data Crown copyright and database right 2013.Contains RCAHMS data Crown copyright 2013.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    8/117

    OHCCMAPP2012-13 Report

    vi

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PILOT PROJECT

    REPORTYEAR 2(2012-13)

    79441.02

    Contents

    List of Illustrations ......................................................................................................... viiiList of Tables .................................................................................................................. ixList of Photos .................................................................................................................. x

    1. INTRODUCTION ............................................................................................................. 11.1. SCOPE OF THE 2012OHCCMAPP ................................................................................... 12. FIELD SITES .................................................................................................................. 42.1. STULAIGH,SOUTH UIST (2628THJUNE 2012) ................................................................. 42.2. HARTAVAGH,SOUTH UIST (29THJUNE1STJULY 2012) .................................................... 5

    Diver Survey (29th J une 1st J uly 2012) ......................................................................... 92.3. LOCHEYNORT,SOUTH UIST............................................................................................. 11

    Diver Survey (2nd J uly 2012) ......................................................................................... 112.4. KALLIN,GRIMSAY ........................................................................................................... 12

    Coastal Survey (3rd J uly 2012) ...................................................................................... 122.5. MANISH,HARRIS ............................................................................................................ 13Diver Survey (4th & 5th J uly 2012) .................................................................................. 132.6. LUNDALE,LEWIS ............................................................................................................ 143. ASSOCIATED SITES: COMMUNITY REPORTS ........................................................ 183.1. UPPER LOCH TORRIDONLUB DUBH-AIRD .................................................................... 18

    Site Background ............................................................................................................ 183.2. LOCH LAXFORD .............................................................................................................. 214. THEMATIC ASSESSMENTS ....................................................................................... 234.1. INTERTIDAL STRUCTURES ............................................................................................... 23

    Survey and Recording ................................................................................................... 23Yairs and their influence on geomorphology ................................................................. 25Identifying parameters for surveying intertidal features ................................................ 27Interpretation and Comparison ...................................................................................... 28

    4.2. LITHICARTEFACTS IN THE INTERTIDAL ZONE................................................................... 31Lub Dubh-Aird ............................................................................................................... 31Assemblage taphonomy ................................................................................................ 36Inter-tidal geomorphology ............................................................................................. 36Grimsay Flint ................................................................................................................. 37

    4.3. THE GEOARCHAEOLOGY OF INTERTIDAL PEATS &SEDIMENTS......................................... 384.4. AERIAL PHOTOGRAPHY &PHOTOGRAMMETRY................................................................ 444.5. PROSPECTING FOR PALAEOLANDSCAPE POTENTIAL ........................................................ 47

    Publicly-available Geophysical Datasets ...................................................................... 47Data Management ......................................................................................................... 49Multibeam Bathymetry (SA7: Sound of Harris, SA16) .................................................. 49Bathymetric LiDAR (SA7: Sound of Harris) ................................................................... 52

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    9/117

    OHCCMAPP2012-13 Report

    vii

    Today ............................................................................................................................ 54Mesolithic (c. 7000 BC) ................................................................................................. 57Neolithic (c. 3800 & 2500 BC) ....................................................................................... 62Bronze Age (c. 2000 BC) & Iron Age (c. 700 BC) ......................................................... 63Viking (AD 800) ............................................................................................................. 634.6. AREAS OF POTENTIAL PALAEOLANDSCAPE PRESERVATION (APPENDIX III) ....................... 63Context .......................................................................................................................... 63Inundated platforms ...................................................................................................... 64Inundated coastal plains ............................................................................................... 64Inundated embayments ................................................................................................. 64Inundated faults ............................................................................................................. 65Multibeam Bathymetry (SA16: East Loch Roag & West of Lewis) ................................ 66

    5. CONCLUSIONS ............................................................................................................ 685.1. PROJECTAIMS &OBJECTIVES REVISITED ....................................................................... 68

    Engagement .................................................................................................................. 68Engagement into Practice ............................................................................................. 69

    Enhancing Datasets ...................................................................................................... 69Developing a Hebridean Model & Site Prospection ...................................................... 69Developing Methodologies ............................................................................................ 69Informing Cultural Heritage Management ..................................................................... 70

    5.2. NEXT STEPS ................................................................................................................... 706. RECOMMENDATIONS ................................................................................................. 717. REFERENCES .............................................................................................................. 72APPENDIX I: GAZETTEER ................................................................................................... 75GAZETTEER OF CULTURAL HERITAGE FEATURES OF INTEREST (OHCCMAPP2012) ................ 75

    Stulaigh ......................................................................................................................... 75Hartavagh ...................................................................................................................... 75Grimsay ......................................................................................................................... 76Locheynort, South Uist .................................................................................................. 76Lundale, Lewis .............................................................................................................. 77

    APPENDIX II: PALAEOGEOGRAPHICAL RECONSTRUCTIONS ...................................... 78APPENDIX III: AREAS OF POTENTIAL PALAEOLANDSCAPE PRESERVATION IN THESOUND OF HARRIS .............................................................................................................. 79APPENDIX IV: ENGAGEMENT WITH THE FISHING INDUSTRY: SCOPING REPORT ..... 80

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    10/117

    OHCCMAPP2012-13 Report

    viii

    List of Illustrations

    Figure 1: Field plan of Stulaigh farmstead, South Uist, J uly 2012. The rocky coast lies in thenorthwest corner of the plan (RCAHMS Crown Copyright 2012). ............................................ 5Figure 2: Field Plan of southern quadrant of Hartavagh inlet, J uly 2012 (RCAHMS CrownCopyright 2012). The large yair in the west of the drawing was examined during thegeotechnical survey of the inlet and is thought to be contemporary with at least one phase ofoccupation at the site. .............................................................................................................. 6Figure 3: Borehole locations in the Hartavagh intertidal zone. Transect 2 and 3 arecharacterised by less than half a metre of marine mud overlying bedrock. Submerged peatdeposits were recovered from Transect 1. Coordinate grid is in BNG (WA Coastal & Marine2011). ....................................................................................................................................... 9Figure 4: Georeferenced AP of Hartavagh inlet. Nine dry-stone structures are visible in theintertidal zone. Elevations relative to mOD highlight the marked differences in elevationbetween groups of structures. The vertical offset between the dark blue and dark red featuresis around 2m. Contains Ordnance Survey data Crown copyright and database right 201323Figure 5: Elevation (mOD) of intertidal features at Hartavagh, South Uist. Location oftopographic transects A-A (westernmost transect) and B-B (easternmost transect) aremarked. Contains Ordnance Survey data Crown copyright and database right 2013 ........ 24Figure 6: Topographic cross-section (A-A) across yair Hartavagh 8 (at 5m) and intertidalwalls at 45 and 50 m, respectively. Vertical scale corrected to OD at Newlyn, Cornwall. ...... 25 Figure 7: Topographic cross-section (B-B) across intertidal wall feature Hartavagh 9 (at105m). Vertical scale corrected to OD at Newlyn, Cornwall. .................................................. 25Figure 8: Elevation (mOD) of yair structure at Stulaigh, South Uist. Location of topographictransect C-C is marked. Contains Ordnance Survey data Crown copyright and databaseright 2013 ............................................................................................................................... 26Figure 9: Topographic cross-section (C-C) across yair Stulaigh North. The yair is at 20m.

    Vertical scale corrected to OD at Newlyn, Cornwall. .............................................................. 27

    Figure 10: Summary of selected surveys of intertidal wall structures relative to OD with localtidal ranges. Average elevations of all survey points for each structure are indicated by thedata points; vertical error bars depict the standard deviation of the mean elevation. Data fromthe Scilly Isles is included for comparison. ............................................................................. 28Figure 11: Schematic cross-section of Lub Dubh-Aird beach and intertidal zone indicatingtaphonomic pathway for lithic artefacts to enter the intertidal zone. Simplified core sectionshighlighting extant beach sand (orange) overlying lagoon silty clays (grey) are indicated. .... 36Figure 12: Reported flint raw material from the intertidal zone at Kallin, Grimsay ( WACoastal & Marine 2011, Getmapping 2011). ....................................................................... 37Figure 13: Borehole locations at Hartavagh (Photo: WA Coastal & Marine 2011). ................ 38Figure 14: Core profile of Transect 1 at Hartavagh. Core 1-7 is probably related to the

    inundated course of a freshwater stream that enters the inlet in the southeast. Blue circlesdenote radiocarbon samples in Core 1-4. The vertical scale accompanying TR1-4 denotesdowncore depth and elevation (mOD) in parentheses). ......................................................... 39Figure 15: Dated buried peats from the Hartavagh core with relative sea level models(redrawn from Shennan et al. 2006): sea level index points from the Hebrides, green crosses,and sea level limiting points, red crosses. .............................................................................. 42Figure 16: Inferred palaeo-shorelines based on general local bathymetry relative to boreholesurvey containing the dated peats within the Hartavagh inlet (Table 8). Sample location ishighlighted (brown circle) (Contains Ordnance Survey data Crown copyright and databaseright 2013; Contains data from Garmin BlueChart 2013). .................................................. 43Figure 17: Still of a 3D photogrammetry model of the River Balgy terraces in Upper LochTorridon, looking south (made using Autodesk 123D Catch). ................................................ 46Figure 18: Bathymetry datasets assessed by WA C&M. Contains Ordnance Survey data Crown copyright and database right 2013 .............................................................................. 48

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    11/117

    OHCCMAPP2012-13 Report

    ix

    Figure 19: Preliminary multibeam bathymetry for Sound of Harris palaeogeographic testmodel, c. 8000 BP. Northton is shown by the green circle. The dashed line indicates currentMLWS; Green zone in the bathymetry dataset indicates terrestrial land above MHWS; theorange zone indicates the intertidal zone based upon RSL of -10m (Shennan et al. 2006); the

    Yellow zone indicates RSL at -20m based on Lambeck (1993), without a tidal range; the bluezone indicates bathymetry greater than -20m OD. Contains Ordnance Survey data Crowncopyright and database right 2013 ......................................................................................... 50Figure 20: Interpreted palaeogeographic model for the Sound of Harris c. 8000 BP in thevicinity of Northton, Harris. See the legend of Figure 19 for details. The purple outlineindicates the interpreted extent of the intertidal zone. Contains Ordnance Survey data Crown copyright and database right 2013 .............................................................................. 52Figure 21: RSL models for prehistoric palaeogeography in the Sound of Harris. The trend lineis a second order polynomial function, error bars highlight the 5m tidal range incorporatedinto the models. ...................................................................................................................... 54Figure 22: Selected areas highlighting the representation of the modern configuration of theSound of Harris. Contains Ordnance Survey data Crown copyright and database right

    2013 ....................................................................................................................................... 55Figure 23: Northeast Ensay, the distribution of the modern coast and the modelled(HAT/LAT) intertidal zone agree well at the edge of the model. Some occlusions, gaps in thedata exist. The resolution of the data is sufficient to record coastal dunes, dykes and otherlinear boundaries on Ensay. The merging of the multibeam sonar and LiDAR datasets isvisible in the upper right of the image, due to differences between the cell-size resolutions inthe rasters (Contains Ordnance Survey data Crown copyright and database right 2013).. 55Figure 24: Dun Innisgall in its present day context; a small islet within intertidal zone atCarminish, Harris (Contains Ordnance Survey data Crown copyright and database right2013). ..................................................................................................................................... 56Figure 25: Modelled coastal geomorphology at Taraloch (Contains Ordnance Survey data Crown copyright and database right 2013). ........................................................................... 57Figure 26: Calibrated radiocarbon dates (2) from submerged and intertidal peats Pabbay,Sound of Harris (Ritchie 1985) (IntCal 09, OxCal 4.1). .......................................................... 58Figure 27: Calibrated radiocarbon date envelopes from submerged and intertidal peatsPabbay, Sound of Harris vs. Depth (Ritchie 1985) (IntCal 09, OxCal 4.1). ............................ 58Figure 28: Fault topography in southeast of the Sound of Harris (Mesolithic B scenario).Dashed black line represents modern coastline. Note the complex networks of islands andintertidal areas linked by narrow seaways; providing considerable coastal resources andaccessibility by boat (Contains Ordnance Survey data Crown copyright and database right2013). ..................................................................................................................................... 60Figure 29: Lewis combined multibeam bathymetry (Marine Scotland / BGS). Vertical scalerefers only to Lewis multibeam, not Sound of Harris coverage. Yellow, orange and red zones

    overlap with the Mesolithic B model from the Sound of Harris (Northton site is marked).SRTM dataset: J arvis A., H.I. Reuter, A. Nelson, E. Guevara, 2008, Hole-filled seamlessSRTM data V4, International Centre for Tropical Agriculture (CIAT), available fromhttp://srtm.csi.cgiar.org. .......................................................................................................... 66Figure 30: Extent of multibeam bathymetry dataset of East Loch Roag within the parametersof model Mesolithic B (low-tide c 10.5m OD) (orange dot within larger red zone), c. 15x15m).Contains Ordnance Survey data Crown copyright and database right 2013, (data suppliedby Marine Scotland 2013) ...................................................................................................... 67

    List of Tables

    Table 2: Casualties from Loch Laxford, dating to c.19th Century. ........................................... 21

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    12/117

    OHCCMAPP2012-13 Report

    x

    Table 3: Proposed parameters underpinning the cataloguing and assessment of intertidalstructures. ............................................................................................................................... 27Table 4: Summary of Community-gathered lithics from Lub Dubh-Aird (Ballin 2012) ............ 32Table 5: Summary of flint artefacts recovered from gridded survey (Ballin 2012). ................. 33Table 6: Summary of lithic analysis from test pitting campaign (Ballin 2012). ........................ 33Table 7: Summary of lithic artefacts recovered from LDA sites 1 4 (Hardy et al. 2012). ..... 34Table 8: AMS radiocarbon dates from the buried peat at Hartavagh, South Uist indicatingearly Holocene dates for the accumulation of the peat. ......................................................... 40Table 9: Major locations photographed during aerial survey to Upper Loch Torridon withRCAHMS (25/07/2012). ......................................................................................................... 44Table 10: Photogrammetry models produced in 2012............................................................ 45Table 11: Parameters used within Sound of Harris test palaeogeography model and ........... 49Table 12: Parameters used for palaeogeography models for periods outlined in Table 13 ... 53Table 13: Palaeogeography parameters for selected archaeological periods. ....................... 53

    List of PhotosPhoto 1: Stulaigh environs (A. Bicket 2012). ............................................................................ 4Photo 2: Panorama of Stulaigh yair environs, the incoming tide reaches far up thestreambed. The remains of the yair are visible beneath seaweed to the left of centre (A.Bicket 2012). ............................................................................................................................ 5Photo 3: Hartavagh inlet on the rising tide. The sea lies beyond the campsite to the right ofshot; Eilean Dubh is the larger of the two islets in the middle distance in the intertidal zone(A. Bicket 2012, made using AutoStitch.net). ........................................................................... 6Photo 4: Panoramic view from RCAHMS survey base station looking NE. Coring site islocated in the open area of marine mud between the white house ruin and the islets (A.Bicket 2012, made using AutoStitch.net). ................................................................................ 7Photo 5: intertidal stone-built structure (WA 79441_10) in northeast Locheynort, South Uist,J uly 2012 which was identified from APs in the first year of OHCCMAPP (WA Coastal &Marine 2012). ......................................................................................................................... 11Photo 6: Panoramic view of a boat naust at Locheynort (J . Benjamin 2012). ........................ 11Photo 7: Coastal survey at Grimsay (J . Benjamin 2012). ....................................................... 12Photo 8: Community finds of ceramics and a hammer stone (left) recovered from foundationcutting for house construction in southeast Grimsay, (right) recovered form eroding hillockbehind post office at Benbecula Airport (J . Benjamin 2012). .................................................. 13Photo 9: Panorama of intertidal inlet Ob Leasaid, Manish, Harris, surveyed by divers (J .Benjamin 2012). ..................................................................................................................... 14Photo 10: Aerial photograph of Lundale (looking west) taken during 2011 OHCCMAPPcampaign. The surveyed area is the isolated basin to the left of shot (J . Benjamin 2011). The

    arrow indicates the eroding peat horizon containing prehistoric wood. .................................. 15

    Photo 11: Fieldwork at Lundale. Truncated peat deposits, snorkel survey, and augersampling next to a possible causeway or yair, respectively (J . McCarthy 2012). ................... 16Photo 12: Aerial Photograph of Lub Dubh-Aird, Upper Loch Torridon at mid-tide, lookingsoutheast (photo: J . Benjamin 2012). The main implementiferous cove is in the lower rightnext to the end of the road. .................................................................................................... 18Photo 13: Low tide at Lub Dubh-Aird (April 2012, photo: J . Benjamin 2012). The investigationof this site reflects work that was carried out in collaboration and resource sharing with Prof.Hardy who is Principal Investigator at Lub Dubh-Aird. ........................................................... 19Photo 14: Selected worked lithics from Lub Dubh-Aird (Courtesy of K. Hardy 2012) ............ 20Photo 15: Panorama of Northton, Harris looking west east; Toe-head to the left, themountains of Harris to the right. Note the rocky coastal geology overlain by veneers of glacial

    till, Holocene sand and peat. The shallow nearshore waters would have provided a widercoastal fringe during around c. 6500 BC (WA C&M 2011, made using AutoStitch.net). ........ 61

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    13/117

    OHCCMAPP2012-13 Report

    xi

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    14/117

    OHCCMAPP2012-13 Report

    1

    OUTER HEBRIDES COASTAL COMMUNITY MARINEARCHAEOLOGY PROJECT

    REPORTYEAR 2(2012-13)

    79441.02

    1. INTRODUCTION

    1.1. SCOPE OF THE 2012OHCCMAPP

    1.1.1. Following on from the baseline data gathering, initial outreach and fieldwork of Year1, some of the most promising leads were followed up during Year 2. Incorporatingthe three themes developed in Year 1:

    x Marine Resource Exploitation;x Maritime History and Transport; and,x Submerged Prehistory Potential.

    1.1.2. The objectives were to:

    x engage with the local community through existing and newly formedknowledge networks, friendships and contacts, public lectures and mediainterviews in order to access a living and finite knowledge base;

    x assess the results from this engagement process and apply them to furtherfield investigation;

    x focus on under-represented areas, particularly the east coasts of thearchipelago (i.e. complementing SCAPEs previous work with a focus on theseabed and shorelines that remain un-surveyed);

    x enhance local and national datasets; through the addition of new sites andenhancement of records of existing sites located across the coastal, intertidaland marine zones;

    x begin to establish a model for site discovery in the marine environment of theOuter Hebrides;

    x identify specific locations for future study which would use investigativetechniques such as marine geophysics, geotechnical (coring) assessment andarchaeological diving;

    x help inform future management of the Outer Hebrides marine environment.

    1.1.3. Six locations were investigated across South Uist, Grimsay, Harris, and Lewis, incollaboration with RCAHMS staff Dr Alex Hale, George Geddes and Kevin Grant,and Dr Robert Lenfert.

    1.1.4. A total of 39 coastal and intertidal structures were recorded this year (Appendix I);the majority were previously unrecorded and required specialist field investigation

    and recording.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    15/117

    OHCCMAPP2012-13 Report

    2

    1.1.5. Additional fieldwork was undertaken in Upper Loch Torridon to investigate reports ofunderwater Mesolithic material, led by Prof. Karen Hardy. A further aerialphotography campaign was undertaken to gather resources for future research andsite prospection.

    1.1.6. Available bathymetry datasets were obtained for the Sound of Harris and west Lewiscoasts to investigate palaeogeography scenarios for prehistory and historic periodsin the Islands (Appendix II) and areas of interest for prospecting for submergedprehistory (Appendix III).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    16/117

    OHCCMAPP2012-13 Report

    3

    FIELD SITES

    Manish, Harris, J uly 2012 (WA Coastal & Marine 2012)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    17/117

    OHCCMAPP2012-13 Report

    4

    2. FIELD SITES

    2.1. STULAIGH,SOUTH UIST (2628THJUNE 2012)

    2.1.1. Access to Stulaigh, an abandoned farmstead, was made by sea courtesy of J JMcDonald of Locheynort. Access was made on an open plateau above the sea cliffsto the east of the 1st and 2nd Edition OS mapped extent of the Stulaigh farmstead(Photo 1). Four sites were recorded in the field for the first time during theOHCCMAPP survey (Appendix I).

    Photo 1: Stulaigh environs (A. Bicket 2012).

    2.1.2. The environs of the site are generally constrained by uplands on the south, west,and north and by a small river running eastward on the north-most side of the valley.At the head of this small river is a large yair which is quite clearly defined in plan.

    2.1.3. A further, smaller yair is located at the base of the cliffs below the main area ofbuildings at Stulaigh in what appears to be a relict stream channel. The stonework isarranged at a break of slope at the northwest edge of the cove, Caolas Stulaigh.

    2.1.4. The farmstead itself consists of a series of dry-stone buildings which havedeveloped between the 1st and 2nd edition OS maps with further developments post-dating these records. The buildings are concentrated towards the cliff-side with alarge sheepfold occupying the plateaux directly above the cliff. Byres, cottages andstorehouses are inferred uses for the remaining buildings and through discussionswith J J McDonald, who knew the occupants of the farmstead, the extendedMcFarlane family of shepherds and fishermen prior to abandonment in the early 20th

    century, sometime after 19111.

    2.1.5. The rest of the valley is divided into an array of field plots with relatively clearlypreserved boundaries and traces of rig and furrow / feanichan, bisected by a smallstream running through the middle of the valley. A series of drains have been cutacross the cultivated land which are quite clearly visible today.

    2.1.6. Detailed mapping at 1:500 was undertaken by RCAHMS using plane table and Self-Reducing Alidade (SRA) with additional survey undertaken using dGPS, especiallyrecording of the yairs and their immediate surroundings (Figure 1).

    1 http://canmore.rcahms.gov.uk/en/site/126011/details/south+uist+kyles+stuley/ (last accessed

    11/04/2013).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    18/117

    OHCCMAPP2012-13 Report

    5

    Figure 1: Field plan of Stulaigh farmstead, South Uist, July 2012. The rocky coast lies

    in the northwest corner of the plan (RCAHMS Crown Copyright 2012).

    2.1.7. A series of measurements on the larger northern yair (CANMORE ID#319226) atBagh Na Cairidh Moire were made by dGPS (Photo 2) (access with the surveyequipment to the smaller feature (ID#319225) was hampered due to poor weather).A plan, topographic cross-section and spot heights of believed-to-be in situ wallelements were made as well as the position of the tide (Photo 2).

    Photo 2: Panorama of Stulaigh yair environs, the incoming tide reaches far up thestreambed. The remains of the yair are visible beneath seaweed to the left of centre(A. Bicket 2012).

    2.2. HARTAVAGH,SOUTH UIST (29THJUNE1STJULY 2012)

    2.2.1. Following the identification of several intertidal structures during the initial phase ofOHCCMAPP, some of which may be yairs or causeways, the site was targeted for

    further investigation. 20 features were recorded for the first time during theOHCCMAPP survey and have been archived within CANMORE (Appendix I).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    19/117

    OHCCMAPP2012-13 Report

    6

    2.2.2. Hartavagh is a small inlet south of Lochboisdale with a cluster of post-medievalbuildings located around a small intertidal basin containing several islets within asmall valley orientated SW-NE (Photo 3). Several other infilled (by blanket peat)valleys and freshwater lochs are located to the southeast and southwest,

    respectively.

    Photo 3: Hartavagh inlet on the rising tide. The sea lies beyond the campsite to theright of shot; Eilean Dubh is the larger of the two islets in the middle distance in theintertidal zone (A. Bicket 2012, made using AutoStitch.net).

    2.2.3. Access to Hartavagh was made by boat from Lochboisdale courtesy of MarineHarvest. On the vessel the team met Norman McIsaac whose grandfathers croft islocated in the area. The team was deposited on a gravel beach on the eastern sideof the inlet, just north of Eilean Dubh.

    Figure 2: Field Plan of southern quadrant of Hartavagh inlet, July 2012 (RCAHMSCrown Copyright 2012). The large yair in the west of the drawing was examined duringthe geotechnical survey of the inlet and is thought to be contemporary with at leastone phase of occupation at the site.

    2.2.4. A recent fire appeared to have cleared much of the low scrub from the southeasternside of the inlet making access and visibility preferentially possible there.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    20/117

    OHCCMAPP2012-13 Report

    7

    2.2.5. With diving capability added to this part of the fieldwork an inter-disciplinaryinvestigation was undertaken over the course of 3 days. RCAHMS worked to recordthe extant buildings, visible cultivation and other aspects of the onshore andintertidal landscape.

    2.2.6. The valley is reportedly divided into at least 6 crofts one of which is owned by thefather of one of the Marine Harvest staff. Several 17/18th century blackhouses and19th century whitehouses were identified by RCAHMS forming the basis of theirterrestrial survey. The footings of a bridge and a revetted wall supported the carttrack which runs around the fringes of the inlet and appears to head off northtowards Lochboisdale. What appeared to be a small boulder-built quay and otherintertidal walls are visible near to the clustered buildings on the southwest shore aswell as at least four yairs.

    2.2.7. Evidence for extensive management of field systems, peat cuttings and modern fishfarming is also prevalent within the valley.

    2.2.8. Two possible prehistoric hut circles were identified during the survey. One on thesoutheastern ridge of the valley which overlooks a wide, peat-infilled valley withevidence for a small stream draining towards Loch Moraidh to the south. Anotherpotential prehistoric hut circle overlooks Loch Moraidh to the south of the Hartavaghinlet. This may indicate that the peat-filled valley between Hartavagh and LochMoraidh was a focus of prehistoric activity, of currently indeterminate age. Evidenceof contemporary landuse may be preserved under the blanket peat in the valleyfloor.

    2.2.9. RCAHMS also identified a possible field boundary within the intertidal zone on theseaward flank of the smaller islet adjacent to Eilean Dubh (Photo 4).

    Palaeoenvironmental survey of the intertidal zone was made by hand auger alongthree transects (Figure 3). Coring at the highest point of the inlet adjacent to theRCAHMS base-station identified an inundated peat horizon at c. 0.5m depthoverlain by marine mud and sand. dGPS survey of all intertidal structures within theinlet was undertaken to identify the archaeological and palaeolandscape context ofthis peat which may be later prehistoric or younger in date. This peat horizon alsoprovides a sea-level index point. Samples of the upper peats were retrieved forradiocarbon dating.

    Photo 4: Panoramic view from RCAHMS survey base station looking NE. Coring site islocated in the open area of marine mud between the white house ruin and the islets(A. Bicket 2012, made using AutoStitch.net).

    2.2.10. dGPS survey was made of the exposed yairs and intertidal structures and coringlocations. In conjunction with the Stulaigh survey data it is possible to begincompiling a database of intertidal features relative to a standard datum which mayfacilitate analysis of preferred location in the tidal range, a basic relative dating tool(in conjunction with detailed chronological understanding of the associatedsettlements) and identification of walls vs. yairs. In some cases it may be possible to

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    21/117

    OHCCMAPP2012-13 Report

    8

    identify functionally different elements with detailed survey of intertidal and terrestrialzones. At Hartavagh there does appear to be groupings in elevation of discreteintertidal structures. The curvilinear yairs group at around -1m to -1.7m OD, whereasthe other linear structures in the intertidal zone are at graduate between -0.3m to

    1.7m OD.

    2.2.11. dGPS survey was made of the exposed yairs and intertidal structures and coringlocations. In conjunction with the Stulaigh survey data it is possible to begincompiling a database of intertidal features relative to a standard datum which mayfacilitate analysis of preferred location in the tidal range, a basic relative dating tool(in conjunction with detailed chronological understanding of the associatedsettlements) and identification of walls vs. yairs. In some cases it may be possible toidentify functionally different elements with detailed survey of intertidal and terrestrialzones. At Hartavagh there does appear to be groupings in elevation of discreteintertidal structures. The curvilinear yairs group at around -1m to -1.7m OD, whereasthe other linear structures in the intertidal zone are at graduate between -0.3m to

    1.7m OD.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    22/117

    OHCCMAPP2012-13 Report

    9

    Figure 3: Borehole locations in the Hartavagh intertidal zone. Transect 2 and 3 arecharacterised by less than half a metre of marine mud overlying bedrock. Submergedpeat deposits were recovered from Transect 1. Coordinate grid is in BNG (WA Coastal& Marine 2011).

    2.2.12. Assuming a relationship to mean sea level is meaningful for assessing thefunctionality of yairs the hypothesis that structures at or above OD within Hartavaghare walls, causeways or boundaries rather than yairs. Dating of the structures is notdirectly possible no in situ sediments or material was recovered during augeringthat could permit chronometric dating.

    Diver Survey (29th June 1st July 2012)

    2.2.13. Afternoon dives at a high tide by J ohn McCarthy (J M) and Robert Lenfert (RL) onday one and RL and J onathan Benjamin (J B) on day two. RCAHMS team identifiedonshore buildings to survey and record. Photography and general survey of theintertidal features, all of which are stone-built lines which are either causeways or

    fishtraps. Only very limited material is present in the sub-tidal area, finds consistentirely of modern debris, which includes some metal and ceramic objects. No

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    23/117

    OHCCMAPP2012-13 Report

    10

    objects of historic value/interest were encountered. Conditions were generally verygood, with visibility between 5-15 metres at all times. No major currents or hazardsencountered. Heavy seaweed cover, especially near shore (and on the largestones), makes for some difficulty identifying any material present on or under the

    seabed. Marine sediments were stony and or gravel near shore, with marine siltfilling the basin around the island (Eilean Dubh) in the centre of the head of the inlet.Some scoured bedrock is also present. A freshwater burn may be contributing to thesedimentation of the inlet. There is abundant sea life, especially crab and sealspresent. Underwater survey was completed and the area has been covered. Novisible evidence for submerged peat, although intertidal coring did confirm there issome potential for it to exist under the marine silts; there is confirmed peat depositsin the intertidal zone that exist below the low water mark. The intertidal ischaracterised by peat deposits and/or (predominantly) bedrock below marinedeposits. At the western end of the intertidal zone of the inlet, the marine depositsare exposed at low tide over a wide area; some of this overlies intertidal peat,including at least one core taken near the white house on the eastern side of the

    inlet. Water temperature was 10C. Snorkel survey did not produce results other thanto investigate the linear features identified by aerial surveys. Photographs weretaken of the underwater stone rows. In total 2 dives and two snorkel surveys wereconducted from the head of the inlet to the small cove on the western side of theinlet, near the narrows that separate the sheltered environment with the open lochand Minch. The team was transferred back to Lochboisdale by Marine Harvest andduring the return leg the RCAHMS team made a brief visit to Castle Calvay2 at thehead of Lochboisdale and completed a photographic survey.

    2http://canmore.rcahms.gov.uk/en/site/10130/details/south+uist+calvay+castle+calvay/ (last accessed

    17/07/2012)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    24/117

    OHCCMAPP2012-13 Report

    11

    2.3. LOCHEYNORT,SOUTH UIST

    2.3.1. Four intertidal features (probably causeways) linking smaller islets to the coast wererecorded during the survey at Locheynort (Appendix I: Gazetteer). One was

    previously identified from APs in Year 1 (WA 79441_10).

    Diver Survey (2nd July 2012)

    Photo 5: intertidal stone-built structure (WA 79441_10) in northeast Locheynort, SouthUist, July 2012 which was identified from APs in the first year of OHCCMAPP (WACoastal & Marine 2012).

    2.3.2. The WA Coastal & Marine dive team continued their fieldwork with a transfer toLocheynort. Upon arrival they made contact with Alexander McDonald, whosefather, Donald McDonald was born in 1898 in South Loch Boisdale, raised his familyin North Locheynort where they now hold three homes and practice small-scalefarming and fishing (Photo 6).

    Photo 6: Panoramic view of a boat naust at Locheynort (J. Benjamin 2012).

    2.3.3. A walkover survey of the northern part of Locheynort from the end of the public roadto the northern side. A number of tidal features were noted, mainly stone walls.Some features have previously been recorded in the From Mountains to Machairsurvey (Moreland 2012), e.g. WA_79441_8 = 194, perhaps indicating that the study

    area was surveyed at a high tide in 1988. In the afternoon Alexander McDonaldtransferred the team to Sloc Dubh at the sheltered NE limit of Locheynort in his own

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    25/117

    OHCCMAPP2012-13 Report

    12

    fishing boat. The team transferred to the shore and undertook a scuba survey ofpart of the loch edge. The depth was approximately 1-3.5 metres and the seabedwas found to consist of loose soft marine sediments. The edge of the loch washeavily covered in seaweed and visibility was further reduced by the curiosity of the

    abundant local seal population. The conditions for archaeological survey were highlylimited and no further dives were undertaken. Upon return to the village anextensive snorkel survey was undertaken of the area to test for the possiblepresence of features relating to the post-medieval harbour believed to be in the areaaround Sloc Dubh (Moreland 2012). The seabed consisted of soft sediments acrossthe centre of the loch with loose boulders and seaweed along the margins. Thedepth in the centre of the channel meant that the seabed could not be clearly seen.No features of cultural heritage interest were noted. Further scuba survey in thisarea is recommended only after establishing sediment and/or possible marinegeophysics interpretation to evaluate the presence of features or seabedcomposition.

    2.4. KALL IN,GRIMSAY

    Coastal Survey (3rd July 2012)

    2.4.1. The team transferred to Kallin, Grimsay and made contact with local resident, MarieStewart who has been involved in amateur archaeological projects. Three possiblelithics were given to the survey team by Marie for further analysis. A walkoversurvey of the harbour area at Grimsay was undertaken and a number of fishtraps/causeways were recorded with GPS and photography (Photo 7). At the lowerlimit of the intertidal zone these features do not appear on the 2005 Coastal ZoneAssessment of Grimsay (SCAPE 2005) probably due to a high tide during thesurvey.

    Photo 7: Coastal survey at Grimsay (J. Benjamin 2012).

    2.4.2. The findspot of the possible lithics was also visited. At the end of the walkover theteam visited a local fisherman, Ian Macaskill, who had recovered numerous pieces

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    26/117

    OHCCMAPP2012-13 Report

    13

    of prehistoric pottery and lithics from two sites in the local area (Photo 8). Theseincluded decorated prehistoric pot sherds including rims and bases and a number ofprobable hammer stones. A photographic record of the material was made and thelocation of the findspots was recorded (Figure A1.4). Local residents were

    encouraged to report their findings to Treasure Trove Scotland. The team madetheir way to the Bernera ferry and transferred to South Harris.

    Photo 8: Community finds of ceramics and a hammer stone (left) recovered fromfoundation cutting for house construction in southeast Grimsay, (right) recoveredform eroding hillock behind post office at Benbecula Airport (J. Benjamin 2012).

    2.5. MANISH,HARRIS

    2.5.1. The team camped at the next survey site at Manish and made contact with a locallandowner Ian McDonald. He reported the presence of a nearby unrecorded wreck.This was first discovered by his parents and is believed to have been a coal-carryingship. The wreck is believed to be fully submerged at low tide but in relatively shallowwater just to the south of a tidally exposed rock marked as Sgoan on the 1:10,000Ordnance Survey maps. Ian McDonald reported that locals had been able tosalvage coal from the wreck. Although the weather was very calm, no survey wasmade of the reported shipwreck as it lay in open water and the scale of the diveoperation did not permit for diving deeper than 10 metres or diving in exposedlocations outside sheltered, benign conditions due to Health and Safety constraints.

    Diver Survey (4th & 5th July 2012)

    2.5.2. A snorkel survey was made of the inlet at Manish, Ob Leasaid (Photo 9). The initialplan had been to undertake a series of transects across the bay but it was foundthat even at low tide the very centre of the inlet was too deep to see. Instead asurvey was made of the edges of the inlet and the shallower areas where gravelbanks and rock outcrops reduced the depth. Survey was concentrated on the areasin front of the visible traces of post-medieval settlement on the shoreline. A largebody of modern material was noted, particularly 19th and 20th century pottery (noneof which was recovered). The majority of the inlet was comprehensively surveyed bysnorkel.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    27/117

    OHCCMAPP2012-13 Report

    14

    Photo 9: Panorama of intertidal inlet Ob Leasaid, Manish, Harris, surveyed by divers(J. Benjamin 2012).

    2.5.3. A small bay to the SW of Ob Leasaid was noted to have a notable series ofsheltering reefs or geological faults which protected it from the open sea andappeared to form an attractive natural harbour, split into three distinct areas eachbordered to the south by a large transverse wall-like outcrop, each having a gap

    which might allow vessels to pass through. The shallowest of these, at the northernend of the bay was intertidal and drained almost completely at low tide. A very richcollection of 19th and 20th century pottery and other material was noted although noolder material was noted. A snorkel survey of the entire bay was undertaken at lowtide. Although the geological features were confirmed to form a strong natural barrierextending several metres below the waterline the survey was hampered by thepresence of seaweed. A small percentage of the area was clear of seaweed andrevealed a clean gravel and shell seabed composition. A concentration of largeglass jars were noted heavily encrusted with marine organisms. These were beyondfree-diving limits and none were recovered. They may relate to an act of deliberatedumping. A similar cache had been noted at the mouth of Ob Leasaid during theprevious years survey. The team then split, with Dr. Lenfert returning to North Uist.

    Dr. Benjamin and J ohn McCarthy continued on to survey the final site at Lundaletidal pond.

    2.6. LUNDALE,LEWIS

    2.6.1. The submerged bog at Lundale (Photo 10), a small inlet on south Loch Roagoriented roughly north-south was investigated by divers in J uly 2012. The area ismarked as a tidal pond on modern OS mapping and is separated from the mainbody of Loch Roag by a small rocky islet with shallow bedrock sills on either side ofthe islet. The area has previously been visited by STUA (IJ NA 1992) who identifiedthe remains of buried wallsvisible at low tide beneath a horizon of buried willowand birch trees in a tidal pool at the south end of the bay The remains are

    probably Mesolithic (IJ NA 1992:163). The OHCCMAPP visit located walls similar toother boulder built structures in the islands and maybe related to a yair or otherunidentified intertidal structures. The wood horizon is likely to be mid-Holocene,stratigraphically beneath Holocene blanket peat.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    28/117

    OHCCMAPP2012-13 Report

    15

    Photo 10: Aerial photograph of Lundale (looking west) taken during 2011 OHCCMAPPcampaign. The surveyed area is the isolated basin to the left of shot (J. Benjamin2011). The arrow indicates the eroding peat horizon containing prehistoric wood.

    2.6.2. The snorkel survey at Lundale was undertaken at low tide over two days (5th

    & 6th

    J uly 2012). A walkover survey of the area was undertaken and safe entry points forthe snorkel survey were identified. A number of interesting features were notedincluding submerged peats containing large amounts of wood including numerouslarge branches. Near the mouth of the tidal pond the tidal currents had created aneroded channel approximately 25 metres in length through in situ peats, exposing asignificant section. On shore several cores were also taken through terrestrial andintertidal peats, showing a depth of up to 1.7 metres of peat overlying a stony andpresumably post-glacial surface. A possible fish-trap was noted at the edge of thebasin, running from the shore in an S-shaped curve to a small island of preservedpeat within the basin. Cores taken around the fish trap and island showed furtherevidence of significant deposits of submerged peats overlying glacial clay and

    overlain by marine sediments.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    29/117

    OHCCMAPP2012-13 Report

    16

    Photo 11: Fieldwork at Lundale. Truncated peat deposits, snorkel survey, and augersampling next to a possib le causeway or yair, respectively (J. McCarthy 2012).

    2.6.3. The tidal pond contains evidence of inundated woodland which has been inundatedby an expanding valley peat, which has in turn been inundated by rising eustatic sealevel once the bedrock sills have been overtopped.

    2.6.4. The site therefore represents opportunities for examining Holocene sea-level rise aswell as woodland and archaeological landscape development prior to eustatic sealevel inundation. The full power of the tides energy appears to be reduced by the

    narrow access and islet seaward of the tidal pond. Observed bathymetry in the pondindicates a small channel being apparent within the midst of the pond to a depth ofaround 150 cm with the landward flanks being covered in silt and marine mud undera water depth of around 20 40 cm. Preservation of inundated peat and woodlandlayers was observed to be good. Substantial lengths of intact roundwood are visiblein the base of the tidal pond as are eroded beds of peat along the edge of theprobably tide-cut channel.

    2.6.5. Two short cores were recovered by the divers close to a small relict peat island(adjacent to an intertidal structure) in the southwest of the inlet and another towardsthe centre of the tidal pond at the base of the tide-cut channel in 0.4 m and 1.2 mwater depth, respectively. Both indicate the preservation of woody peat around

    40cm thick overlying a deposit of fine-grained marine silty-clay underlying the extantmarine mud that has accumulated across much of the pond. The full depth of thepreserved deposits within the tidal pond could not be retrieved at this time. Therepeated sequence of deposits might indicate that the surface of the inundated bogslopes downwards towards the centre of the tidal pond.

    2.6.6. It appears that in both Hartavagh and Lundale, preservation conditions exist wheresediments of terrestrial origin remain in intertidal areas (cf. Lbke et al. 2011). Bothsites have generally similar topographic and bathymetric characteristics (small isletsand relatively restricted tidal access between them). Opportunities for detailedpalaeoenvironmental analysis, sea-level investigations and associatedpalaeogeographical reconstructions clearly exist within these locations. They also

    provide parameters for identifying areas of sediment preservation and for developingsite location models.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    30/117

    OHCCMAPP2012-13 Report

    17

    ASSOCIATED SITES:COMMUNITY REPORTS OUTSIDE OF THE WESTERN ISLES

    Lub Dubh-Aird, Upper Loch Torridon facing south (photo: J . Benjamin 2012)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    31/117

    OHCCMAPP2012-13 Report

    18

    3. ASSOCIATED SITES: COMMUNITY REPORTS

    3.1. UPPER LOCH TORRIDONLUB DUBH-AIRD

    Site Background

    3.1.1. The investigation of Lub Dubh-Aird reflects work that was carried out in collaborationand resource sharing with Prof. Hardy who is Principal Investigator at this site.Following a Community report of microliths from a beach in the south east of UpperLoch Torridon (Photo 12), several short campaigns of field investigation wereundertaken during April, May and J uly 2012. In collaboration with Prof. Karen Hardy(ICREA) an integrated series of terrestrial, intertidal and underwater surveys andtestpit excavations were made at the site. The following sections contain elementsalso reported in Hardy et al. (2012).

    Photo 12: Aerial Photograph of Lub Dubh-Aird, Upper Loch Torridon at mid-tide,

    looking southeast (photo: J. Benjamin 2012). The main implementiferous cove is inthe lower right next to the end of the road.

    3.1.2. The site is a series of small coves on a small bedrock promontory. A faultline runsroughly E-W at the base of the promontory creating sharply stepped bedrocktopography. The promontory is covered in shallow blanket peat overlying thebedrock. There is evidence of a 20th century fish farm in the cove3 and a modernunmetalled access road has been built (probably sometime after the 1950s frommapping evidence4). The earliest mapped location in the vicinity of the peninsula isArdmore on J ohn Thomsons Atlas of Scotland map of 18325, the peninsula

    3

    http://her.highland.gov.uk/SingleResult.aspx?uid=MHG49631(last accessed 17/12/2012).4http://geo.nls.uk (last accessed 10/09/2012).

    5http://maps.nls.uk/atlas/thomson/index.html (last accessed 10/09/2012).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    32/117

    OHCCMAPP2012-13 Report

    19

    directly to the west of the site. A couple of small bothys or other structures6 arepreserved unroofed at the entrance to the promontory adjacent to the road; they arenot recorded on the first and second edition OS maps. Between the First andSecond editions (between 1875 1905 surveys) the peninsula much of the inland

    area seems to have come under forestry plantation where previously the OS havemapped the peninsula as a boggy area. At this time a coastal access road was built;previously access around the south of the loch was made by a route that themodern main road follows to the south. Vegetation cover today is mainly heatherscrub and wetland sedges and grass at the peat fringes of the cove with a smallplanted coppice of pines (perhaps a remnant of the historical plantation).Rhododendrons cover most of the remaining landscape, at great density.

    3.1.3. The area is interesting archaeologically. An Ahrensburgian point was found at LochShieldaig, nearby (Ballin 2003), and up to 18 rock shelters with lithics or lithicscatters have been found in the area around Loch Torridon (Hardy & Wickham-J ones 2009) (Hardy et al. 2012).

    3.1.4. A possible rock shelter has been reported previously7 in addition to a rock shelterfeature investigated in more detail during this project8 and initial evidence of the flintscatter9 analysed below.

    3.1.5. To date several thousand lithics have been recovered from the small cove (Hardy etal. 2012), mostly from the intertidal zone.

    Photo 13: Low tide at Lub Dubh-Aird (April 2012, photo: J. Benjamin 2012). Theinvestigation of this site reflects work that was carried out in collaboration andresource sharing with Prof. Hardy who is Principal Investigator at Lub Dubh-Aird.

    3.1.6. The sharp condition of the lithics and debitage indicates they have not beenreworked far or perhaps for very long (Photo 14). It was observed early on thatmicroliths were present within the peat deposits fringing the cove, with a

    concentration of lithics present on the back beach.

    6http://her.highland.gov.uk/SingleResult.aspx?uid=MHG44530;

    http://her.highland.gov.uk/SingleResult.aspx?uid=MHG27043;http://her.highland.gov.uk/SingleResult.aspx?uid=MHG49635;http://her.highland.gov.uk/SingleResult.aspx?uid=MHG49636(last accessed 17/12/2012).7

    http://her.highland.gov.uk/SingleResult.aspx?uid=MHG49637(last accessed 17/12/2012).8http://her.highland.gov.uk/SingleResult.aspx?uid=MHG54900(last accessed 17/12/2012).

    9http://her.highland.gov.uk/SingleResult.aspx?uid=MHG54901(last accessed 17/12/2012).

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    33/117

    OHCCMAPP2012-13 Report

    20

    Photo 14: Selected worked lithics from Lub Dubh-Aird (Courtesy of K. Hardy 2012)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    34/117

    OHCCMAPP2012-13 Report

    21

    3.2. LOCH LAXFORD

    3.2.1. Following a Community report of a wreck in Loch Laxford, the site has been putforward for inclusion in SAMPHIRE (Scotlands Atlantic Maritime Past: Heritage,

    Investigation, Research & Education), the successor project to OHCCMAPP.

    3.2.2. The material from the site includes a range of metal and wooden debris and a largearrow-shaped anchor with flukes, possibly of 19th century origin. The site is partiallyprotected by sand.

    3.2.3. Few wrecks with known positions exist for Loch Laxford. A number of casualties /recorded losses specifically relating to 19th century wrecks in the Loch are archivedby RCAHMS and other sources. Some possibilities are outlined below.

    Wreck Description Source

    Helena Wooden schooner, cargo of bog ore. Lost16th

    J anuary 1879 after being stranded onCrow Island

    http://canmore.rcahms.gov.uk/en/site/220938/details/helena+crow+island+loch+laxford+north+minch/

    PhoenixLost ?1842, en route Peterhead toLiverpool.

    http://canmore.rcahms.gov.uk/en/site/275364/details/phoenix+loch+laxford+north+minch/

    CharlotteMcKenzie

    Stranded on rocks during bad weather onapproach to Cape Wrath, [mid-19thcentury]

    http://www.east-durham.co.uk/seaham/colliers_logbook.htm

    Table 1: Casualties from Loch Laxford, dating to c.19th

    Century.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    35/117

    OHCCMAPP2012-13 Report

    22

    THEMATIC ASSESSMENTS

    Loch Eynort, South Uist, J uly 2012

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    36/117

    OHCCMAPP2012-13 Report

    23

    4. THEMATIC ASSESSMENTS

    4.1. INTERTIDAL STRUCTURES

    Survey and Recording

    4.1.1. Intertidal structures at Hartavagh (Figure 4, Figure 5) and Stulaigh (Figure 8) weresurveyed using dGPS equipment to provide centimetre precision to measurementsof their position. Topographic cross-sections highlighting the location of the inter-tidal structures within their intertidal and fluvial settings are presented for Hartavgah(Figure 7, Figure 6) and Stulaigh (Figure 9).

    Figure 4: Georeferenced AP of Hartavagh inlet. Nine dry-stone structures are visible inthe intertidal zone. Elevations relative to mOD highlight the marked differences inelevation between groups of structures. The vertical offset between the dark blue anddark red features is around 2m. Contains Ordnance Survey data Crown copyright

    and database right 2013

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    37/117

    OHCCMAPP2012-13 Report

    24

    Figure 5: Elevation (mOD) of intertidal features at Hartavagh, South Uist. Location oftopographic transects A-A (westernmost transect) and B-B (easternmost transect)are marked. Contains Ordnance Survey data Crown copyright and database right2013

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    38/117

    OHCCMAPP2012-13 Report

    25

    -2.0

    -1.5

    -1.0

    -0.5

    0.0

    0.5

    1.0

    1.5

    2.0

    2.5

    020406080100120

    Figure 6: Topographic cross-section (A-A) across yair Hartavagh 8 (at 5m) and

    intertidal walls at 45 and 50 m, respectively. Vertical scale corrected to OD at Newlyn,Cornwall.

    -2

    -1

    0

    1

    2

    3

    4

    5

    6

    7

    0 20 40 60 80 100 120 140

    Figure 7: Topographic cross-section (B-B) across intertidal wall feature Hartavagh 9(at 105m). Vertical scale corrected to OD at Newlyn, Cornw all.

    4.1.2. At Stulaigh, the larger yair located in the intertidal mouth of the stream at CaolasStulaigh was surveyed using dGPS (Figure 8). The smaller yair located at the footof the cliff beneath the main buildings was too dangerous to survey due to seaweedcover and poor weather conditions. As at Hartavagh the emplaced boulders thatmake up the yair are laid in a concave form relative to the receding tide. There issubstantial disturbance at the apex of the Stulaigh yair which is assumed to haveoccurred at the point of maximum flow from the stream and perhaps tidal currentsacting to undermine the footing of the boulders. This is reflected in the 0.5 mdifference in the height of the boulders measured in Figure 8, where boulders havebeen moved downstream and downslope (Figure 9).

    Yairs and their influence on geomorphology

    4.1.3. The recorded boulder-built yairs in cross-section highlight the capturing of fluvial andintertidal sediments. This typically occurs on the upstream side as highlighted by thereduction and near plateaux observed in the stream-bed gradient at around 20-25 malong profile.

    4.1.4. In lieu of wooden or other organic components to these features the accumulation of

    sediment provides some resource for sediment dating by optical methods; however,it is likely that only a terminus ante quem date would be gathered. The influence of

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    39/117

    OHCCMAPP2012-13 Report

    26

    key taphonomic factors such as tidal reworking of sediments and incompletebleaching of luminescence signals upon the reliability of the dates would besite-specific.

    Figure 8: Elevation (mOD) of yair structure at Stulaigh, South Uist. Location oftopographic transect C-C is marked. Contains Ordnance Survey data Crowncopyright and database right 2013

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    40/117

    OHCCMAPP2012-13 Report

    27

    -1.5

    -1.0

    -0.5

    0.0

    0.5

    1.0

    1.5

    2.0

    051015202530354045

    Figure 9: Topographic cross-section (C-C) across yair Stulaigh North. The yair is at20m. Vertical scale cor rected to OD at Newlyn, Cornwall .

    Identifying parameters for surveying intertidal features

    4.1.5. Intertidal structures recorded at Hartavagh (Figure 4, Figure 5) and Stulaigh(Figure 8) provide a preliminary dataset for investigating methodologies andanalyses. Additional datasets from around the British Isles have been sought toprovide context on spatial, temporal and morphological variability and use ofintertidal structures. By surveying these structures in 3 dimensions and calibratingthem relative to a defined datum (in this case Ordnance Datum, OD) it is possible to

    lay the foundations for future comparative research.

    4.1.6. Assuming that some of the structures are indeed structures for trapping fish andother marine species a number of parameters can be derived from the surveydataset and available literature to provide critical elements for future catalogues.These can be classified under Morphological, Interpretational and Survey fields(Table 2).

    Morphology Interpretation Survey

    Morphology Geomorphological Context Local Tidal RangeFunctional elevation Archaeological Context MHWS / HATConstruction Material Date of construction MLWS / LATConstruction Method Period of Use Chart Datum (CD) offset

    Method of Use Port (CD)Species sought Coordinate System / Projection

    Geoid / DatumLatitude / EastingLongitude / NorthingElevation (to fixed datum)Lat / Easting ErrorLon / Northing ErrorElevation (to fixed datum) Error

    Table 2: Proposed parameters underpinning the cataloguing and assessment ofintertidal structures.

    4.1.7. Within the context of reviewing the literature, the latter column, Survey parameters(Table 2) are likely to be restricted to relatively recent projects with access to dGPS

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    41/117

    OHCCMAPP2012-13 Report

    28

    or well-established local benchmarks which permit precise correlation to a fixeddatum (most usefully for the purposes of comparison, OD or CD).

    4.1.8. As J ordan et al. (2010) have shown, rationalising coastal features (geomorphology

    or archaeology) which are formed relative to their contemporary sea level is complexwithin the context of modern fixed datums such as CD or OD. Unless a site is closeto a port with a CD offset or Newlyn in Cornwall (OD) a far-field sites relationship tosea level is not particularly well constrained. However, the use of local benchmarksmay inhibit site and inter-study comparison. To facilitate both aspects of geodesyand local sea level variability it is necessary to define datums, projections,underpinning geoid models as well as local and regional sea level variables (Table2).

    Interpretation and Comparison

    4.1.9. Recent survey data from the Scilly Isles (courtesy of CISMAS10) is compared to oursurveyed examples from Hartavagh and Stulaigh (Figure 10).

    -3.0

    -2.0

    -1.0

    0.0

    1.0

    2.0

    3.0

    0.00 2.00 4.00 6.00 8.00 10.00 12.00

    lon/lat

    elevation(mO

    D)

    Hartavagh Stulaigh Scilly Isles (Cecil 1983) Samson Flats (CISMAS 2010)

    Hartavagh measured Low Tide

    Stulaigh measured Low Tide

    Lochboisdale High Tide

    Stornoway High Tide

    Lochboisdale Low Tide

    Stornoway Low Tide

    St Mary's High Tide

    St Mary's Low Tide

    Figure 10: Summary of selected surveys of intertidal wall structures relative to ODwith local tidal ranges. Average elevations of all survey points for each structure areindicated by the data points; vertical error bars depict the standard deviation of themean elevation. Data from the Scilly Isles is included for comparison.

    4.1.10. The partitioning of intertidal structures and yairs is clearly shown at Hartavagh witharound 1m difference in elevation ranges between two groups of structures (Figure

    10). The features also differ on morphological grounds, the lower group being10

    http://www.cismas.org.uk/docs/SF10%20Report%20WEB%20comp.pdf(last accessed 27/08/2012)

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    42/117

    OHCCMAPP2012-13 Report

    29

    curvilinear features extending across the tidal range similar to yairs identified acrossthe Outer Hebrides (see OHCCMAPP 2011 report). The upper group aremorphologically diverse and contain short walls joining the coast at one end, orappear to be short causeways between islets (Figure 4).

    4.1.11. Immediately, the site-specific, vernacular nature of these features is highlighted bythe elevation of the larger of the two Stulaigh yairs. The elevation of the Stulaigh yaircorresponds to the lower range of the Hartavagh upper intertidal structures. Tidalrange is critical for interpreting these features however the broad range of the tide atall sites makes detailed interpretation difficult. For example the yairs at Hartavagh liewithin the lower half of the tidal range, the walls in the upper half. Broadly speakingthese features at Hartavagh and Stulaigh are probably of a similar age, c. 18th - 19thCentury, any sea level differences on a multi-decadal scale are effectively engulfedby the local tidal range.

    4.1.12. The use of intertidal structures as fish traps suggests they are accessible at some

    point during the low tide however the local geomorphology and topography, speciessought and method of use may all have a bearing on how the tidal elevation of thefeature is useful as a parameter for comparison. Some large wooden-framed trapsin the Severn Estuary for example must be emptied by hand during the low-tide andare dependent on foot-access along their length and therefore must be located inthe tidal range to allow sufficient time for these tasks (Chadwick andCatchpole 2010).

    4.1.13. Stone fish weirs recorded along the Somerset coast of the Severn Estuary duringthe recent RCZA are directly comparable to many of the curvilinear stone-built yairsobserved in the Outer Hebrides, especially those with a gut or sluice at the apex ofthe structure. Baskets or other devices to trap fish are installed at the gut and the

    fish are channelled along the interior of the arms as the tide falls. So-called neaptide weirs (Chadwick and Catchpole 2010: 55) permit fishing during the majority ofthe tidal cycle.

    4.1.14. To maximise the period where fish can be collected from the ebbing tide the mostlikely elevation for a yair to be located is logically close to the mean tidal range. Inthe case of Hartavagh and Stulaigh, south and north of Lochboisdale, respectivelythe mean between HAT and LAT listed in TotalTides (taken from Admiralty data) isaround -0.36 mOD. The average elevation of the lower group is -1.1520.3 mOD.The Stulaigh yair lies 0.3m OD within the upper range of the measured tidal rangesuggesting that the yair at Stulaigh could have been operated during parts of thetidal cycle tides that the yairs at Hartavagh could not be. The difference in elevationis most likely due to differences in the topography between the two locations. Thecomplex islet and stream morphology at Hartavagh relatively restricts where a yaircould be positioned to create a standing pool upstream, whereas the flatter, opentopography at Stulaigh means greater flexibility for emplacing the structure withinthe tidal range.

    4.1.15. Interpreting these tidal relationships raises several questions. Due to the range oftidal variability in these field locations what resolution of interpretation of featurestidal elevation is valid? Is categorisation to the upper, mean or lower range of tidalvariability diagnostic? Does a deviation from the mean tidal range indicate an agefactor relative to a previous period of lower sea level (i.e. does the c.80cm difference

    between mean tidal range and mean feature elevation indicate age)?

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    43/117

    OHCCMAPP2012-13 Report

    30

    4.1.16. Within the context of relative sea-level model and sea-level index points theuncertainty in both chronometric dating and the taphonomy of the indicative strataand peat compaction for instance make inferences at the sub-metre scaleproblematic. In the absence of preserved wooden elements in their construction, it is

    also less likely that a clear age model can be constructed for yairs and otherconstructed features (now) located in the intertidal zone. In some cases it might bepossible to recover stratified sediments suitable for radiocarbon or OSL dating whichhave a clearly defined stratigraphic relationship to the construction of the yair;detailed investigation of individual features is required, either by augering ortest-pitting. Augering around the features at Hartavagh produced no in situsediments, although a notable accumulation of marine mud was noted form withinthe features (at Stulaigh too) indicating that over time mobile sediments reworked inthe tidal cycle may serve to inhibit the efficiency of stone-built weirs.

    4.1.17. The vertical range of these parameters serves to further reduce the level ofempirical diagnostic information that can be recovered from yairs, on their use and

    tidal relationship.

  • 7/30/2019 Outer Hebrides Coastal Community Marine Archaeology Pilot Project. Year 2 2012-13

    44/117

    OHCCMAPP2012-13 Report

    31

    4.2. LITHICARTEFACTS IN THE INTERTIDAL ZONE

    Lub Dubh-Aird

    4.2.1. The investigation of this site reflects work that was carried out in collaboration and

    resource sharing with Prof. Hardy who is Principal Investigator at Lub Dubh-Aird.The beach at Lub Dubh-Aird (NG 8723 5505, site name LDA 1) was brought to ourattention by Prof. Karen Hardy, by local resident Andrew Patrick has beenrecognising lithics here for several years, having walked across most beaches in thearea. He claims that apart from occasional finds elsewhere, this is the only beach toproduce substantial numbers of lithics. After examination of his lithics collection,which confirmed that the assemblage contained knapped artefacts, a small projectwas established to try to determine the nature of the archaeology of the beach andits surroundings, and to try to locate the origin of the lithic artefacts. The sharpcondition of the lithics and debitage indicates they have not moved far or perhapsbeen exposed for very long. It was also observed early on that lithics were presentwithin the peat deposits fringing the cove, with a concentration of lithics present onthe back beach. See the Data Structure Report for a full report11 (Hardy et al. 2012).

    4.2.2. Regional sea-level reconstructions are relatively poorly constrained in the region.The Applecross model of Shennan et al. (2006) suggests there is potential for earlyMesolithic (c. 8000 BP) submerged prehistory; with uplift acting to move coastalsites out of the intertidal zone after around 5000 BP. In theory then, there ispotential for Mesolithic cultural heritage to be located on land, in the intertidal zoneand/ or from an underwater source. To test whether there was an underwaterdeposit of early Mesolithic age, a shallow-water survey was undertaken to explorewhether source material for the in-washed lithics lay underwater. A defined depositwas not located but the cover of seaweed and mobile sands on the loch bed may

    preclude detection (Hardy et al. 2012). The focus of the fieldwork became theintertidal and onshore areas of the peninsula.

    4.2.3. An initial, non-disturbance underwater survey was conducted using a 100m linearpattern with visibility 5m in clear water to a maximum of 2m depth. The shallow-water survey was conducted from 100m horizontal distance from the low water markbut identified no surface artefacts on the seabed which is composed of pebbles andmedium grain sand in these shallow conditions. It is likely that this area is affectedby some tidal and wave activity, despite its very sheltered locale. A further snorkelsurvey around the cave was conducted at a later date, also with no identifiablear