Map Introduction: South Uist Map 6

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Adela Holland
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2 Map Introduction: Map 6 This map section covers part of the west coast of. It extends from Cill Donnain to Ardvule and onwards to Ormacleit. There is no modern settlement within the coastal zone but there are traces of past cultivations and field boundaries in the area. Of the 5 sites recorded in this area, were previously known. They include a kelp workers settlement (SU58), a shipwreck (SU75) and the broch of Dun Vulan (SU59), which has been partially excavated, consolidated and which is scheduled. The broch has been slightly damaged in the recent storm. The foreshore is composed mainly of sand, with rock platform visible around the Ardvule promontory. The hinterland is covered with blown sand. The coastline is eroding and much of the hinterland lies below 0m OD. 7

3 Built Heritage & Archaeology Map 6 SU 56 NF Croic a Tuath Kelp pit in section 8th-st C AD Fair Nil SU 57 NF Rubha Aird a'mhuile/rubha Ardvule Mound Indeterminate Fair Nil SU 58 (NF7NW) NF Rubha Aird a'mhuile/rubha Ardvule Kelp workers settlement 8th-st C AD Fair Nil SU 59 (NF7NW) NF Scheduled (60) Dun Vulan Broch and settlement st Mil BC/st Mil AD Fair Monitor SU 75 (NF7SW800) NF Bornish, Croic a Tuath The 'Argonaut', wreck of cargo vessel 8th-st C AD N/A Nil 8

4 Built Heritage & Archaeology Map 6 Map 7 Scale: :5,000 Survey Date: Feb 005 Crown copyright. All rights reserved. Historic Scotland Licence No c SU57 SU59 SU58 SU56 SU75 Map 5 Protected Ancient Monument or area of Designated Wreck Built Heritage & Archaeology Monument formally proposed by Historic Scotland for scheduling or wreck for designation Listed Historic Building Undesignated wreck Known ancient monument Site found by this survey Site complex 9

5 Hinterland Geology & Coastal Geomorphology Map 6.Cill Donnain NF km Mainly Sand Coast edge >5m Blown sand This coastal stretch is uniform throughout with coastal dunes typically -5m in height and the hinterland is comprised of dunes and machair blown sand. Boulders and shingle mantle the cliffs along the base of the dunes with sand foreshore evident along this section..loch Aird a Mhuile headland NF km Rock Platform Coast edge <5m This headland is geomorphologically complex and is all rock platform apart from a small sand and shingle beach at NF The headland is connected by a small tombolo to the dunes and machair areas although this has been modified by the construction of a trackway for use by the MOD. Extensive deposition is evident across the headland and is particularly noted at NF 7099 to the west, where shingle and cobble ridges have been formed. This ridge which stretches the length of the SW and W area of the headland is over-steepened on the landward slope. In this area the foreshore is comprised of rock platform and organic deposits have been exposed due to severe erosion. Shingle and cobble spreads are evident into the loch, which covers the surface of the platform across the headland.. Casteal Ormacleit NF km Mainly Sand Coast edge >5m Blown sand Along the northern section, the erosional dune cliff face is mantled by shingle. Locally, the erosional effects of the January hurricane are evident these being mostly evidence for flood overtopping of sections of dunes (e.g. NF 7909). Boulder overwash plumes are noted on the top of the machair at NF 706. The cliffs are >5m along this section. The foreshore is sand and shingle/gravel and at NF 700 a series of gravel cusps occur on the foreshore. These cusps cover an area of 00m in length and individual cusps are c. 0m x 5m width and are approximately m thick. 40

6 Hinterland Geology & Coastal Geomorphology Map 6 Scale: :5,000 Survey Date: Feb 005 Crown copyright. All rights reserved. Historic Scotland Licence No c Rock platform Low edge <5m Foreshore Mainly sand Mainly alluvial/marine mud Modifiers Cliff >5m Man made barrier Marsh Shingle/storm bank Human disturbance Hinterland Drift Drift on visible rock Raised beach etc Blown sand 6 Glacial sand/gravel Alluvium 5 4 4

7 Erosion Class.Cill Donnain to Loch Aird a Mhuile NF 774 to NF km. Eroding Coastal cliffs everywhere exhibit an erosional cliff face. Also this erosional cliffline along this stretch is characterised by accumulations of shingle that mantle the base of the cliff edge..loch Aird a Mhuile headland NF km Eroding The headland has evidence of severe erosion throughout. The area is marked on Ordnance Survey maps as a Danger Area (Rocket Range). There is a causeway area that is overtopped during high tides. The coastal edge around the headland is estimated here to have undergone 5-0m of retreat during the January hurricane. Evidence for this erosion includes cliff faces cut in glacial drift, supratidal peat and Holocene dune sands. The causeway, itself constructed on a tombolo, is also severely damaged and the trackway across to the island is almost completely destroyed. Extensive erosion has revealed at several locations around headland drift deposits, supratidal peats, relict storm beach horizons and shell middens. Map 6. Loch Aird a Mhuile to Casteal Ormacleit NF 798 to NF km. Eroding This coastal stretch is arcuate in plan and consists of a continuous sequence of coastal dunes. The frequency of aeolian blowouts in this area is conspicuous the most prominent features being a set of three closely spaced blowouts ca m north of the Loch Aird a Mhuile headland 4

0007509 005 c Definitely Accreting Erosion Class Accreting or Stable

8 Erosion Class Map 6 Scale: :5,000 Survey Date: Feb 005 Crown copyright. All rights reserved. Historic Scotland Licence No c Definitely Accreting Erosion Class Accreting or Stable Stable Eroding or Stable Definitely Eroding Accreting and Eroding No access Land below 0m 4

Map Introduction: South Uist Map 1

Map Introduction: South Uist Map 1 96 Map Introduction: Map This map section covers part of the south coast of, including the head of the causeway which links the island to Eriskay. It extends from South Glen Dale to Taobh a'caolas. There