A Regression-Time Stone-Workers' Camp, 33 Ft OD, Lussa River, Isle Of
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A Regression-time Stone-workers' Camp, , LussOD 3 t a3f River, Isl Jurf eo a by John Mercer SUMMARY Lussa Rive yieldes rha dprolifia c quartz-flint industry microlithie ,th c element characterisea y db highly-evolved rodd carbonisean , d organic relics d ochrere , , pumic environmentad ean l evidence. Geological positio typologd nan y suggest sub-divisio Jura'f no s microlithic period into three major phases, with Lussa River in the last; this sequence is supported by C14 dates. Since the new industry is numerically dominated by over three hundred bifacial eclats ecailles, many showing bipolar action, together with peculiar, standardised hammerstones alsn inferree oca b t ,i d that Lussa Rive relate s Oronsae th rwa o dt y 'Obanian' sites, whose stone-flaking seemingly involved little else. Assuming microliths were absentt a r o , least very few, at the Oronsay camps, then the most likely theory seems to be that these were occupied by a people who, though associated with the Jura sites (deer, boar hunting?), were temporarily or per- manently engaged in a pursuit (sealing?) which expended harpoon-heads, bone-working chisels (eclats ecailles) and elongated bevel-ended scraper-rubbers (the latter made on pebbles and long bones, perhaps used either because most suitabl r becaus o eOronsan a Lusss a f o e, ayor River suggests regionaa , l scarcity of flint). On Lealt Bay evidence the land-recovery movement began about the middle of the Atlantic perio 425c d( 0 BC); Lussa River dry-seaso,a n camp partiall whollr yo y autumnal, belonge th o st time when relative sea-leve certainld ha l y fallen awa possibld yan t ovet morf y2 no r2 e frot thaf s 0 mnit 3 Lussa Glen washing limit of 55 ft OD. Lussa River C14: 2670 ±140 BC (BM-556), 2250 ±100 BC (BM- 555), corrected ages 3450 BC, 2940 BC. The earlier of these, coupled with the Lealt Bay evidence, suggests, very tentatively JurN ,a a land-recover 25-3r pe t y5f rat1 years f eo , wit presene hth t Lussa Glen washing , reacheOD t f limit d5 1 betwee c , n 3200-280. 0BC INTRODUCTION This is the third paper in a series1" which the writer is preparing on prehistoric human activit Jura N firste secondn d yi .Th 1 an 6 2 reports provide essential background: fresh informa- e area'th tio n sno Post-Glacial vegetatio land-sed nan a movement descriptiond an s o tw f o s widely-differing microlithic industries Lussd , an Leal y a BayBa t . REPORT ) Location(a descriptiond an of site (figs 1-4) The Lussa River site (NGR NR 644873) stands at 33 ft OD on a narrow bedrock terrace on sid W f Luss eo e up-valler th o a mile 2 Lusse E Glen sitd W N th y sS es f an ya Ba o , yd som 0 55 e of that at Lealt Bay (the papers on these sites described the region and Lussa Glen). Lussa Wood matura , e plantatio sprucf no pind ean e some saib o edt sixtyn (i year d ol s the background of the photographs of Lussa Bay2), covers the immediate area of the site, which lies at the SE corner of the trees. The lowest conifers stand on the back of a gravel terrace which, 2 | PROCEEDINGS OF THE SOCIETY, 1970-71 Tentsmuir Sands Malcolm's Point LUSSA GLEN 0 Yard10 s NORTH JURA ScotlanS FI G1 d with NE Ireland 3 ; mout JuraN G FI FI GLussf ;2 h o a Glen 500 yd long, reaches to the foreshore at Lussa Bay; up the valley, the plantation continues far . Locaabov sitee OD let abouth o f informatiot , 0 10 t thats ni ,plantin e prio th woode o th rt f go , lowee th aree cultivateds r th hal awa f o f traced an , f agriculturo s facn i tseee e b estilar n o t l there. caveo N r superficiao s l relic f ancieno s t habitation were valleye noteth n di . MERCER REGRESSION-TIMA : E STONE-WORKERS' CAMP, LUSSA RIVER3 , JUR | A (b) Geological and pollen evidence (pi la, figs 3-6) Between OD and the 55 ft OD washing limit (described shortly) of the highest Post- Glacial transgression, Lussa Glen divides into four terraces. The lowest seems likely to consist of deep gravels three th , e uppermos bedroce ar t k forms comparatively thinly coated with more or less unconsolidated materials. lowese th mos d f uppee o an t td Th extensivren e terrace (Tl bees )ha nS mappeO e th y db , s 'Dai1878(a 6in ) l Bhaite r 'tho ' e Drowned Field' explaio T . n this suggestive name local peopl marshpoine w th eno o t y cornee largth a sitee f f juso o r th e o , f fieltW o S d d abouy 0 10 t porphyrite ridge. Yet, for a boggy island like Jura, the probably more extensive Dail Bhaite are reasonabls ai yt remarkabl dryno , y factwetn I . , wher rivee eth r enter uppee sth r regiof no lowese th t terrac lattee eth r bears long runnels paralle watercoursee th o t l n i g trencd du an ,, hD one of the runnels, revealed 27 in of a mixture of sand and silt (on massive boulders, with 2 rolled flint artefacts, one heavily patinated, the other fresh) with its top at 18 ft OD; the runnels prob- ably link with the inactive river-channel to the W of the porphyrite ridge. Probably then, Dail Bhait originalls ewa y thus called afte area'e th r s tendenc floodino yt rivere th jusr y o ,g b t possibly bextraordinariln ya actine y higon y ghb agains r seao , othere archaeologicatth e .Th l significance of l thiriversidT thas sy i an t e camp likele sar havo yt e been washed away poina , t that wile b l returned to shortly. WASHING LUSSA GLEN (MOUTH. N.W. SIDE) 50 Generalised Profile 45 (Unconsolidated Material) 40 35 30 . S.W. PORPHYRITE •25 •20 a____. •15 GRAVEL\jr\r*>v i_i_So • -r-ii •10 HEIGHT OF. .PRESENT. .RIVE R_AJ. _ .LOW WATE. WR- P-^ —— "'' 5 . O.D. Yards________ 500| 550_______650 FIG 4 Generalised profile, Lussa Glen secone Th d terrac (T2crescenticp s i eu ) convexite th , y seawards widd aboud y an ,5 e 2 t below the site. Trenches B and C revealed, upon bedrock, 15 and 30 in respectively of medium find ean gravel (holdin flingtota9 a 2 tf lo artefacts minut9 t whicf o ,bu l eh al chip s were markedly rolled) with a maximum height of 25 ft OD and a minimum of 22 ft OD. The topography is such that neither this nor either of the two terraces above could feasibly be flooded by the river (smsw stricto) either at present or during any Post-Glacial land-sea adjustment, and all unconsolidated material then so m mus consideree b t f estuarindo e origin (i.e. resulting fro highese mth t Post- Glacial transgression). thire r sitTh do e terrace crescentics (T3i ) , paralle thao t l t below excavatioe Th . n showed that the site's zone of the terrace has a gully as its bedrock form. Its long axis along that of the valley gulle th , y dipped widess seaware towardth wa t founfilles e d a t b d an swa d o t dendt I . and levelled by a stony sand (described later). e fourtTh h terrace s muc(T4i ) h more extensive tha e previounth s twoa leve, l square covering the 100 yd from the valley's W wall to the river (which, there, runs past about 30 ft below) and extending the same distance in the upstream direction. The terrace gravels (much PROCEEDINGS OF THE SOCIETY, 1970-71 GULLY (LENGTHWAYS) MIDDL F GULLO E Y FIG 5 Sections, Lussa River panned an , withio dt T3 deepesurface e d th foona an f o rt2 )thaT musn no topographican o t l grounds and because they contain flint artefacts to a depth of several feet (under excavation) be considered to have been laid down by the transgression. These gravels, which reach their maximum (55 ft OD) as a mound just S of the E end of a narrow cross-going bog, are considered to mark the washing limit. Other evidence is that behind the strip of bog there is a change to a steeper slope, whilst there is no bedrock notch where the bog's stream falls into the river, sug- gesting suc hdrainaga e patter youthfuls ni . Sample poller sfo n analysis were obtaine poina t a tg dabou bo fro e mtth fro 1d 1y e mth W valleye walth deen i f o 6 lp , t wherf (fi , blac3 g3 peae s eth k wa t square) suggest6 g Fi .e sth e Sub-Boreath f o pead en tl e begaperiodth d conditiont na Ha . s there remained unchanged MERCER REGRESSION-TIMA : E STONE-WORKERS' CAMP, LUSSA RIVER, JURA C~s. ei— oio •to 80 0 40 0 0 15 0 80 0 Pirns ftlnus Ulmus Corulus Ptrttntaoe. firbortoL J n ii Betula (Juercus rolle.n. 20 0 40 80 40 0 20 Ericaceae Gramineae. •Filitals-s. FIG 6 Pollen diagram, Lussa Wood bog throughout Post-Glacial time this woul surprisingla e db y delayed start enforced an , d cross- going, slowly-blocked drainage behin Boreal-Atlantie dth c transgression's washing-limit gravels seems more likely.