Skip to main content

LUP Student Papers

LUND UNIVERSITY LIBRARIES

OSL dating of the Mesolithic site Nilsvikdalen 7, Bjorøy, Norway.

Jirdén, Elin LU (2022) In Dissertations in Geology at Lund University GEOR02 20221
Department of Geology
Abstract
Luminescence dating is a well-established dating method within geological and archaeological research. However, the use of luminescence dating, and more specifically optically stimulated luminescence (OSL), is currently underutilised in Norwegian archaeology. This study set about determining the suitability of this dating method as a viable option for excavations of Norwegian coastal Stone Age sites. This is done by OSL dating six samples from three superimposed cultural layers at a settlement (Nilsvikdalen 7) at Bjorøy, SW Norway, which has previously been radiocarbon dated to the Late Mesolithic period, and subsequently evaluating the method suitability from the results.
The cultural layers all consist of varying degrees of humus-rich... (More)
Luminescence dating is a well-established dating method within geological and archaeological research. However, the use of luminescence dating, and more specifically optically stimulated luminescence (OSL), is currently underutilised in Norwegian archaeology. This study set about determining the suitability of this dating method as a viable option for excavations of Norwegian coastal Stone Age sites. This is done by OSL dating six samples from three superimposed cultural layers at a settlement (Nilsvikdalen 7) at Bjorøy, SW Norway, which has previously been radiocarbon dated to the Late Mesolithic period, and subsequently evaluating the method suitability from the results.
The cultural layers all consist of varying degrees of humus-rich sand with charcoal, where OSL samples were taken from inside and outside an interpreted hut structure. Quartz OSL dating was carried out using the Single Aliquot Regenerative-dose (SAR) protocol for all six samples and yielded successful results. The samples displayed a strong quartz signal with excellent characteristics. The water content of the site yielded the highest uncertainties for the dose rate determination and was after thorough evaluation determined to ~ 63 – 114%. Dose rate was determined to ~ 2 – 4 Gy/ka. Different age models were applied, where the mean age was chosen for the final age determination. The bottom cultural layer was dated to the Late Mesolithic, with OSL ages of 8.07 ± 0.51 ka and 7.02 ± 0.43 ka inside the hut, as well as 6.60 ± 0.40 ka outside the hut boundary. The middle and upper layers were dated to Late Mesolithic – Early Neolithic, where the middle unit displayed an age of 6.25 ± 0.36 ka and the upper layer yielded ages of 5.56 ± 0.32 ka and 6.94 ± 0.36 ka (all dates inside the hut). Three of the samples overlap with the corresponding radiocarbon dates, whilst the other three do not statistically agree (values outside of ± 2 σ) with the radiocarbon dates. For the samples without statistical agreement, the OSL ages produced are younger than the corresponding radiocarbon dates.
For future OSL dating it is suggested to, if possible, take a control sample of recent or known age from a site area to reduce possible uncertainties in the luminescence age determination process. Given the successful dating of the Nilsvikdalen 7 site, this project demonstrates how OSL dating could provide a good solution for future dating of Norwegian coastal Stone Age sites. (Less)
Abstract (Swedish)
Luminiscensdatering är en väletablerad dateringsmetod inom geologisk och arkeologisk forskning. Dock är användandet av luminiscensdatering, mer specifikt optiskt stimulerad luminiscens (OSL), fortfarande underrepresenterat inom norsk arkeologi. Denna studie ämnar utreda lämpligheten av denna dateringsmetod som ett användbart alternativ för utgrävningar av Stenålderslokaler på den norska kusten. Detta genomförs genom att OSL-datera sex prover från tre successiva kulturlager av en boplats (Nilsvikdalen 7) på Bjorøy, sydvästra Norge, vilken tidigare har kol-14-daterats till Senmesolitikum. Från resultaten kan sedan metodens lämplighet utvärderas.
Kulturlagren består alla av varierande grad humus-rik sand med träkol, där OSL proverna togs... (More)
Luminiscensdatering är en väletablerad dateringsmetod inom geologisk och arkeologisk forskning. Dock är användandet av luminiscensdatering, mer specifikt optiskt stimulerad luminiscens (OSL), fortfarande underrepresenterat inom norsk arkeologi. Denna studie ämnar utreda lämpligheten av denna dateringsmetod som ett användbart alternativ för utgrävningar av Stenålderslokaler på den norska kusten. Detta genomförs genom att OSL-datera sex prover från tre successiva kulturlager av en boplats (Nilsvikdalen 7) på Bjorøy, sydvästra Norge, vilken tidigare har kol-14-daterats till Senmesolitikum. Från resultaten kan sedan metodens lämplighet utvärderas.
Kulturlagren består alla av varierande grad humus-rik sand med träkol, där OSL proverna togs från in- och utsida av vad som tolkats som en hydda. OSL-datering av kvarts genomfördes för alla sex prover genom användande av SAR protokollet och gav framgångsrika resultat. Proverna uppvisade en stark kvartssignal med utmärkta egenskaper. Vattenhaltsmätningarna resulterade i de största osäkerheterna för bestämning av bakgrundsstrålningen, men bestämdes efter noggrann avvägning till ~ 63 – 114%. Bakgrundsstrålningen bestämdes till ~ 2 – 4 Gy/ka. Olika åldersmodeller applicerades, där medelåldern användes för den slutgiltiga åldersbestämningen. Det understa kulturlagret daterades till Senmesolitikum, med OSL-åldrar av 8.07 ± 0.51 ka och 7.02 ± 0.43 ka inne i hyddan samt 6.60 ± 0.40 ka utanför hyddans gräns. Det mellersta och översta kulturlagren daterades till Senmesolitikum – Tidigneolitikum, där det mellesta lagret gav en ålder på 6.25 ± 0.36 ka och det översta lagret gav åldrarna 5.56 ± 0.32 ka och 6.94 ± 0.36 ka (alla dateringar inne i hyddan). Tre av proverna överlappar åldersmässigt med 14C-åldrarna för respektive lager, medan de andra tre skiljer sig statistiskt (värden utanför ± 2 σ) från 14C-åldrarna. För proverna med statistisk skillnad är OSL åldrarna alla yngre än respektive kol-14-dateringar.
För framtida OSL-dateringar föreslås det att, vid möjlighet, ta ett kontrollprov av recent eller känd ålder från lokalen för att reducera möjliga osäkerheter inom luminiscens-åldersdateringen. Med den lyckade dateringen av boplatsen Nilsvikdalen 7 demonstrerar detta projekt hur OSL-datering kan bidra som ett gott alternativ för framtida dateringar av Stenålderslokaler i den norska skärgården. (Less)
Please use this url to cite or link to this publication:
author
Jirdén, Elin LU
supervisor
organization
course
GEOR02 20221
year
type
H2 - Master's Degree (Two Years)
subject
keywords
OSL dating, luminescence, SAR protocol, water content, archaeology, Late Mesolithic, Norway.
publication/series
Dissertations in Geology at Lund University
report number
633
language
English
id
9096587
date added to LUP
2022-07-31 16:10:54
date last changed
2023-07-30 03:41:55
@misc{9096587,
  abstract     = {{Luminescence dating is a well-established dating method within geological and archaeological research. However, the use of luminescence dating, and more specifically optically stimulated luminescence (OSL), is currently underutilised in Norwegian archaeology. This study set about determining the suitability of this dating method as a viable option for excavations of Norwegian coastal Stone Age sites. This is done by OSL dating six samples from three superimposed cultural layers at a settlement (Nilsvikdalen 7) at Bjorøy, SW Norway, which has previously been radiocarbon dated to the Late Mesolithic period, and subsequently evaluating the method suitability from the results. 
	The cultural layers all consist of varying degrees of humus-rich sand with charcoal, where OSL samples were taken from inside and outside an interpreted hut structure. Quartz OSL dating was carried out using the Single Aliquot Regenerative-dose (SAR) protocol for all six samples and yielded successful results. The samples displayed a strong quartz signal with excellent characteristics. The water content of the site yielded the highest uncertainties for the dose rate determination and was after thorough evaluation determined to ~ 63 – 114%. Dose rate was determined to ~ 2 – 4 Gy/ka. Different age models were applied, where the mean age was chosen for the final age determination. The bottom cultural layer was dated to the Late Mesolithic, with OSL ages of 8.07 ± 0.51 ka and 7.02 ± 0.43 ka inside the hut, as well as 6.60 ± 0.40 ka outside the hut boundary. The middle and upper layers were dated to Late Mesolithic – Early Neolithic, where the middle unit displayed an age of 6.25 ± 0.36 ka and the upper layer yielded ages of 5.56 ± 0.32 ka and 6.94 ± 0.36 ka (all dates inside the hut). Three of the samples overlap with the corresponding radiocarbon dates, whilst the other three do not statistically agree (values outside of ± 2 σ) with the radiocarbon dates. For the samples without statistical agreement, the OSL ages produced are younger than the corresponding radiocarbon dates. 
	For future OSL dating it is suggested to, if possible, take a control sample of recent or known age from a site area to reduce possible uncertainties in the luminescence age determination process. Given the successful dating of the Nilsvikdalen 7 site, this project demonstrates how OSL dating could provide a good solution for future dating of Norwegian coastal Stone Age sites.}},
  author       = {{Jirdén, Elin}},
  language     = {{eng}},
  note         = {{Student Paper}},
  series       = {{Dissertations in Geology at Lund University}},
  title        = {{OSL dating of the Mesolithic site Nilsvikdalen 7, Bjorøy, Norway.}},
  year         = {{2022}},
}