Excavation

Date 15 July 2013 - 23 August 2013

Event ID 994281

Category Recording

Type Excavation

Permalink http://canmore.org.uk/event/994281

HY 303 129 Further investigation of the large Late Neolithic complex on the Ness of Brodgar was undertaken, 15 July – 23 August 2013, in order to characterise more of the structures and activity on the site. Relationships between some of the structures were clarified and a stringent sampling procedure was implemented for tackling the floor deposits. Micromorphic samples were also taken through floor and midden deposits.

In Structure 1 internal floor deposits consisted of extensive occupation layers and discrete patches of occupation and clay floor material around the central hearth and abutting the piers. Small box sections excavated for soil micromorphology sampling revealed a complex floor stratigraphy, c0.13–0.23m thick, consisting of numerous thin occupation and clay floor layers. Externally, excavations on the W side revealed that Structure 1 was built on a sequence of midden and levelling layers (0.52m thick) which seal glacial till. A section through the paving in the intramural passage on the E side of Structure 1 demonstrated that Structure 19 was constructed later than Structure 1. The passage is underlain by a stone-lined drain. To the S of Structure 1, extensive dumps of ashy midden had been heaped around a large orthostat which is aligned on the S entrance. The midden heap also sealed rubble and irregular structural remains which have yet to be excavated. This rubble continued below Structure 11 and this building was constructed at this level. Last season it was established that Structure 21 was constructed just after Structure 1 and more of this building was exposed in 2013. This included the remains of an inner wall face.

The majority of Structure 7 was removed to investigate the underlying remains of Structure 19. Following the excavation of the remaining quadrants of levelling material around the Structure 7 hearth, the hearth itself was removed, revealing an earlier hearth directly below. A possible oven, containing burnt stone, with a flue, was found to the N of the later central hearth. Along with the oven to the S excavated in 2012, the northern oven and sequence of hearths indicates varied and perhaps intensive use of this area (large-scale cooking). Structure 19, and later Structure 7 above, was of piecemeal construction and modification as this area developed, and probably never roofed.

Excavation within the previously exposed NNE portion of Structure 8 was limited to half sectioning the SSW portion of the central hearth, in order to expose burnt deposits suitable for archaeomagnetic dating. The floor deposits in this area of the structure were left in situ until the rest of the structure has been fully exposed.

In the SSW portion of Structure 8, deposits associated with the initial dismantling and decommissioning of the structure were removed. These deposits consisted of interleaved deposits of demolition rubble, including further evidence of dressed roofing stones and deposits of midden material, and sealed floor deposits associated with the use of Structure 8. A further rectangular hearth was partially exposed, which was offset from the central axis of the building, towards Recess 7. In the central area of the SSW portion of Structure 8, a large mound of secondary in situ burnt deposits was revealed, which measured 3m NNE–SSW by 2.2m WNW–ESE. This mound of burnt material is unusual, as it does not appear to be associated with a formalised hearth setting at this level. The sequence of deposits infilling Structure 8 were block sampled for soil micromorphology.

Deposits overlying the outer passageway of Structure 10 were excavated, in order to clarify the stratigraphic relationships between deposits that were infilling Structure 8 and the outer passageway of Structure 10.

In the Central Midden Area between Structures 8 and 12, excavation was limited to clarifying the relationships between a deposit of trample, midden deposits, two clay surfaces and the annexe of Structure 12.

Work in Structure 10 further explored its interior and sequence. Features and deposits relating to the secondary cruciform shaped central chamber were investigated, and removed including several orthostatic arrangements. The two surviving SW and NE later corner buttresses were partially removed. Under the NE one a six knobbed carved stone ball was discovered, while under the SW one a large and elaborately decorated stone block was revealed. Both seem to have formed part of a foundation deposit associated with the secondary reconstruction and remodelling of the interior of Structure 10. The floor of this secondary use sat on a thick, very mixed rubble and clay deposit that is presumed to seal the primary deposits that relate to its original square plan with rounded corners. More of the robber trench infill was removed, particularly around the SE corner, to confirm the original square plan of the interior.

With the removal last year of the upper mass fill layers in Structure 12 deposits were reached that signified a later phase of reuse of the building. A large hearth was revealed in the S half of the building in association with a large spread of cattle bone. A large number of stone roofing slates were also recovered from the interior. In its primary phase Structure 12 had an entrance in its NW corner, and internal buttresses at both ends. This entrance was then blocked and a new narrow entrance was ‘punched’ through its N end when the annexe/porch arrangement was added. The annexe utilised walling from at least two earlier structures that underlie Structure 12.

Work on Structure 14 was confined to its interior floor deposits which were gridded and sampled. The complexity of the floors necessitated two narrow sondage trenches being excavated across them in order illuminate their stratigraphy. These revealed a sequence of numerous floors and potential phases.

Trench T was opened for the first time in 2013. The trench was placed to investigate a c45m diameter mound (HY31SW 20) that rests upon the eastern tip of the spit of land upon which the Ness of Brodgar sits. The mound is clearly defined on its E and S sides, blends into the natural slope on its W side and is partly truncated by the road on its N side. The trench, which was placed to intersect two concentric curvilinear features and a possible enclosure identified through geophysics, measured 7 x 15m and was aligned with its long axis cN–S. The curvilinear features were thought to be revetment walls, which raised the possibility that the mound was a chambered tomb. Accordingly, the principal objective of the excavation was to define the date and type of the mound.

The excavation revealed that the mound (at least in the upper levels so far encountered) was constructed from vast amounts of midden material. A significant later remodelling of the mound was represented by the construction of a revetment wall built to contain a large quantity of rubble and stony soil that seems to form a collared platform around the mound. The midden mound is likely to be Neolithic in date; the date of the remodelling of the mound is uncertain but presumed to be Late Neolithic. Evidence for robbing of the stony platform was provided by a large quarry pit that produced some fragments of iron.

More samples for archaeomagnetic dating were taken from hearths in Structures 8, 12, 14 and 16 by Dr Cathy Batt and Dr Zoe Outram of Bradford University with support from the British Academy. To accompany the large catalogue of Neolithic art already discovered many other examples were revealed and catalogued this season, taking the total number discovered to date to 670.

Report: Orkney HER and RCAHMS

Funder: Orkney Islands Council, Orkney College UHI, Robert Kiln Trust, Orkney Archaeology Society, Orcadian, British Academy and Currie Brothers

Nick Card, ORCA, Orkney College UHI, 2013

(Source: DES)