Current Projects


  • The Last Migration: Improving the shell chronology.

    2006 Marsden Funded research (UOW0502) awarded to Petchey, F., A. Anderson and A.Hogg.

    AIM. To improve the reliability of marine shell radiocarbon (14C) determinations from archaeological sites within the islands of the marginal southwest Pacific and central East Polynesia. The results of this research will not only refine archaeological chronologies within the Pacific that use marine shell, but will also have significance for issues of population mobility and origin using both human bone and associated commensals.1 In particular, the results will be invaluable for those studying the origins and development of Maori. Data obtained during this project will also aid research into coastal geomorphology and climate change in the region.

    For listing of samples collected to date click here.

    Petchey F, A Anderson, A Hogg, A Zondervan, 2008 The marine reservoir effect in the Southern Ocean: an evaluation of extant and new ΔR values and their application to archaeological chronologies. Journal of the Royal Society of New Zealand 38(4): 243-262.

  • Reservoir effects in the Bismarck and Solomon Seas

    Petchey, F., M. Phelan, J.P. White, 2004. New ΔR Values for the Southwest Pacific Ocean. Radiocarbon, 46(2):1005-1014.

    ABSTRACT. ΔR results of known age shells from the Solomon and Coral Seas, and the northwest coast of New Ireland are presented. The results are too few to be conclusive but indicate that ΔR in this region is variable. An average ΔR value of 370 25yrs is recorded for a range of shell species from Kavieng Harbour, New Ireland, and is primarily attributed to weak equatorial upwelling of depleted 14C due to seasonal current reversals. In contrast, values from the Solomon and Coral Seas are lower (average ΔR =45 19 yrs). Higher ΔR values for some shellfish from these two seas is attributed to ingestion of 14C depleted sediment by deposit feeding species.

  • Reservoir effects within Eastern Polynesia
  • Phelan, M. 1999. A ΔR Correction Value for Samoa from Known-Age Marine Shells. Radiocarbon 41(1): 99-101.

    ABSTRACT. A first-order ΔR correction value for marine samples is presented based on 3 radiocarbon determinations of known-age marine shells from Samoa.

  • Reservoir effects and bone dating
  • Petchey, F. and R. Green, 2005. Use of three isotopes to calibrate human bone radiocarbon determinations from Kainapirina (SAC), Watom Island, Papua New Guinea.Radiocarbon,47(2):181-192.

    ABSTRACT. In archaeological dating the greatest confidence is usually placed upon radiocarbon results of material that can be directly related to a defined archaeological event. Human bone should fulfill this requirement, but bone dates obtained from Pacific sites are often perceived as problematic due to the incorporation of 14C from a range of different reservoirs into the collagen via diet. In this paper, we present new human bone gelatin results for two burials from the SAC archaeological site on Watom Island, Papua New Guinea, and investigate the success of calibrating these determinations using dietary corrections obtained from delta34S, delta15N and delta13C isotopes.


    Petchey, F., 2001. Radiocarbon Determinations from the Mulifanua Lapita site, Upolu, Western Samoa. Radiocarbon 43(1):63-68.

    ABSTRACT. The Mulifanua ferry berth has the distinction of being the only site in Samoa with dentate-stamped Lapita wares, and is the most easterly Lapita site in the Pacific. Two new radiocarbon determinations of material associated with Lapita pottery found at Mulifanua are presented. The accuracy of this data is evaluated according to the results of recent re-assessment of pottery from the site, and current theories regarding the age of Lapita settlement in the eastern Pacific. The resulting calibrated radiocarbon ages put occupation of the Mulifanua Lapita site at around 2880-2750 cal BP (930-800 BC). This conclusion is in agreement with the pottery chronology and supports recent hypotheses of rapid Lapita settlement in the Fiji/Tonga region around 2850-2700 cal BP (900-750 BC).

  • Reservoir effects around Australia
  • Ulm, S., 2002. Marine and estuarine reservoir effects in central Queensland, Australia: Determination of ΔR values. Geoarchaeology: An International Journal, 17(4):319-348.

    ABSTRACT.As a component of archaeological investigations on the central Queensland coast, a series of five marine shell specimens live-collected between A.D. 1904 and A.D. 1929 and 11 shell/charcoal paired samples from archaeological contexts were radiocarbon dated to determine local ΔR values. The object of the study was to assess the potential influence of localized variation in marine reservoir effect in accurately determining the age of marine and estuarine shells from archaeological deposits in the area.

  • Reservoir effects and Marine shell habitat
  • Hogg, A.G., T.F.G. Higham, and J. Dahm, 1998. Radiocarbon dating of modern marine and estuarine shellish. Radiocarbon 40: 975-84.

    ABSTRACT. We measured the 14C content of 36 living marine molluscs from Tairua Harbour and the rocky coast of the Coromandel Peninsula of New Zealand. We identified species suitable for radiocarbon dating and show that hte open marine intertidal zone is enriched in14C compared to the open marine subtidal zone or estuary. We also found a uniform 14C distribution in the Tairua harbour, by analyzing samples of the estuarine bivalve Austrovenus stutchburyi collected up to 5km from the harbour entrance.