45 results for Petchey, Fiona

  • Kumukumu 1, a hilltop site in the Aird Hills: Implications for occupational trends and dynamics in the Kikori River delta, south coast of Papua New Guinea

    David, Bruno O.; Aplin, Ken; Petchey, Fiona; Skelly, Robert; Mialanes, Jerome; Jones-Amin, Holly; Stanisic, John; Barker, Bryce; Lamb, Lara (2014)

    Journal article
    University of Waikato

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  • ¹⁴C marine reservoir variability in herbivores and deposit-feeding gastropods from an open coastline, Papua New Guinea

    Petchey, Fiona; Ulm, Sean; David, Bruno O.; McNiven, Ian J.; Asmussen, Brit; Tomkins, Helene; Richards, Thomas; Rowe, Cassandra; Leavesley, Matthew; Mandui, Herman; Stanisic, John (2012)

    Journal article
    University of Waikato

    Herbivorous and deposit-feeding gastropods are a major component of archaeological shell middens worldwide. They provide a wealth of information about subsistence, economy, environment, and climate, but are generally considered to be less than ideal for radiocarbon dating because they can ingest sediment while they graze, inadvertently consuming terrestrial carbon in the process. However, few studies of C-14 activity in herbivores or deposit-feeding gastropods have been conducted into this diverse range of animals that inhabit many environmental niches. Here, we present results investigating ¹⁴C variability in shells belonging to the families Strombidae and Potamididae from the Bogi 1 archaeological site, Caution Bay, southern coastal Papua New Guinea (PNG). These shells make up 39.3% of the shell MNI8 in the excavation units studied and some of these species are the most common taxa of neighboring sites. It would therefore be advantageous to establish if there are any ¹⁴C offsets associated with such animals, and identify those that can give reliable calendar ages. Our methodology combines a high-resolution excavation protocol, selection of short-lived samples identified to species level, and a tri-isotope approach using ¹⁴C, δ¹³C, and delta ¹⁸O to evaluate the source of variability in shells. Our results indicate that considerable variation exists between different species of Strombidae with some inhabiting muddier environments that act as sinks for limestone-derived sediments with depleted ¹⁴C content. The magnitude of variation is, however, overshadowed by that measured in the mudwhelk, Cerithidea largillierti, which has the largest spread in ¹⁴C of any shellfish studied so far at Caution Bay. This animal ingests sediment within the estuary that contains ¹⁴C derived from both enriched and depleted sources.

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  • 14C marine reservoir variability in herbivores and deposit-feeding gastropods from an open coastline, Papua New Guinea

    Petchey, Fiona; Ulm, Sean; David, Bruno O.; McNiven, Ian J.; Asmussen, Brit; Tomkins, Helene; Richards, Thomas; Rowe, Cassandra; Leavesley, Matthew; Mandui, Herman; Stanisic, John

    Journal article
    University of Waikato

    Herbivorous and deposit-feeding gastropods are a major component of archaeological shell middens worldwide. They provide a wealth of information about subsistence, economy, environment, and climate, but are generally considered to be less than ideal for radiocarbon dating because they can ingest sediment while they graze, inadvertently consuming terrestrial carbon in the process. However, few studies of 14C activity in herbivores or deposit-feeding gastropods have been conducted into this diverse range of animals that inhabit many environmental niches. Here, we present results investigating 14C variability in shells belonging to the families Strombidae and Potamididae from the Bogi 1 archaeological site, Caution Bay, southern coastal Papua New Guinea (PNG). These shells make up 39.3% of the shell MNI [minimum number of individuals] in the excavation units studied and some of these species are the most common taxa of neighboring sites. It would therefore be advantageous to establish if there are any 14C offsets associated with such animals, and identify those that can give reliable calendar ages. Our methodology combines a high-resolution excavation protocol, selection of short-lived samples identified to species level, and a tri-isotope approach using 14C, δ13C, and δ18O to evaluate the source of variability in shells. Our results indicate that considerable variation exists between different species of Strombidae with some inhabiting muddier environments that act as sinks for limestone-derived sediments with depleted 14C content. The magnitude of variation is, however, overshadowed by that measured in the mudwhelk, Cerithidea largillierti, which has the largest spread in 14C of any shellfish studied so far at Caution Bay. This animal ingests sediment within the estuary that contains 14C derived from both enriched and depleted sources.

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  • A Pleistocene charcoal drawing or painting from northern Australia

    David, Bruno O.; Barker, Bryce; Delannoy, Jean-Jacques; Geneste, Jean-Michel; Petchey, Fiona; Lamb, Lara (2014)

    Journal article
    University of Waikato

    Although claims are often made that Australia has evidence of some of the oldest rock art in the world and features prominently in rock art studies globally, very little of it is securely dated. Recently the first Pleistocene date for pigment art (painting, drawing, stencil or print) in Arnhem Land was obtained, arguably representing one of the oldest securely dated fragments of buried rock art in Australia (see Aubert 2012 and David et al. 2013a for recent reviews on dating rock art in Australia).

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  • Soils of Seabee Hook, Cape Hallett, northern Victoria Land, Antarctica

    Hofstee, Erica H.; Balks, Megan R.; Petchey, Fiona; Campbell, David I. (2006)

    Journal article
    University of Waikato

    The soils of the Seabee Hook area of Cape Hallett in northern Victoria Land, Antarctica, were mapped and characterized. Seabee Hook is a low-lying gravel spit of beach deposits built up by coastal currents carrying basalt material from nearby cliffs. Seabee Hook is the location of an Adélie penguin (Pygoscelis adeliae) colony which influences the soils with additions of guano, dead birds, eggshells and feathers. A soil-landscape model was developed and a soil association was identified between the soils formed on mounds (relict beach ridges) favoured by penguins for nests (Typic Haplorthel) and the soils in the areas between the mounds (Typic Haplorthel/Typic Aquorthel). Soils formed on the mounds inhabited by penguins contained guano in the upper 50 cm, overlying sub-rounded beach-deposited gravel and sand. Soils between mounds had a thin veneer (< 5 cm) of guano overlying basaltic gravelly sand similar to that in the lower parts of the mound soils. The soils had high concentrations of nitrogen, organic carbon, phosphorus, cadmium, zinc, copper, and increased electrical conductivity, within horizons influenced by penguin guano. Five buried penguin bones were collected from the base of soil profiles and radiocarbon dated. The dates indicate that Seabee Hook has been colonized by penguins for at least 1000 years.

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  • The marine reservoir effect in the Southern Ocean: an evaluation of extant and new R values and their application to archaeological chronologies

    Petchey, Fiona; Anderson, Atholl; Hogg, Alan G.; Zondervan, Albert (2008)

    Journal article
    University of Waikato

    The last phase of human colonisation of the south-west Pacific occurred around the 12th Century AD amongst the islands of the subtropical and temperate zones of the Southern Ocean (i.e., Norfolk Island, the Kermadec Islands, New Zealand and the Chatham Islands) (Fig. 1). Archaeological evidence indicates that initial colonisation of the region was rapid, possibly taking less than 100 years. Unfortunately, the chronology of these events has been largely reliant on charcoal radiocarbon determinations that have not been successful in delineating these changes. This paper investigates the use of marine shell for radiocarbon dating as an alternative to charcoal, with specific focus on variation in the marine 14C reservoir (specifically the ∆R) of Raoul Island (Kermadec Islands), Norfolk Island and Chatham Island (Fig. 2). Results from known-age, pre-AD 1950 shellfish indicate that ∆R values south of the South Pacific Convergence Zone are low compared to those recorded for islands within the South Pacific generally (Fig. 1) (see Petchey et al.in press). An average ∆R value of –19 ± 13 14C yr is recorded for Raoul Island and –49 ± 10 14C yr for Norfolk Island. These values are attributed to heightened absorption of atmospheric CO2 in this region. Extant published ∆R information from New Zealand (Fig. 2A) also suggests a low average ∆R value for these southern waters, but the range of values indicates that considerable variability is possible because of the complex interplay of currents around the New Zealand coastline. In contrast, results from Chatham Island are more variable and much higher (average ∆R = 134 ± 83 14C yr). Stable oxygen and carbon isotope data support the hypothesis that these ∆R values are caused by upwelling and mixing of 14C-depleted water along the Chatham Rise. Comparison of marine and charcoal 14C determinations from archaeological sites on Raoul Island support, within the limits of the available data, the ∆R values obtained, but further analysis is required to establish the stability of this value over time.

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  • Archaeology of Atafu, Tokelau: Some initial results from 2008

    Addison, David J.; Bass, Bryon; Christensen, Carl; Kalolo, John; Lundblad, Steve; Mills, Peter; Petchey, Fiona; Thompson, Adam (2009)

    Journal article
    University of Waikato

    Surface survey, shovel testing, and stratigraphic excavations were done on Atafu Atoll in Tokelau during August 2008. Initial results suggest that Fale Islet has the most potential for further archaeological research. Dense cultural deposits on this islet are >1 m (39 in.) deep. Cultural material recovered includes food bone, fire-affected volcanic rock, tool-grade basalt flakes and tool fragments, Tridacna shell adzes, and pearl-shell fishhook fragments. Dog bone occurs from the earliest deposits through to the late prehistoric, while pig bone is found only in historic contexts. Fish bone is common throughout, and, with the exception of Tridacna, there are few edible mollusk remains. Initial EDXRF (Energy Dispersive X-Ray Fluorescence) analyses have found the basalt to be consistent with documented sources on Tutuila, Samoa. Basal radiocarbon dates from two excavation units are 660-540 cal. BP and 500-310 cal. BP (at 2σ).

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  • High-resolution radiocarbon dating of marine materials in archaeological contexts: radiocarbon marine reservoir variability between Anadara, Gafrarium, Batissa, Polymesoda spp. and Echinoidea at Caution Bay, Southern Coastal Papua New Guinea

    Petchey, Fiona; Ulm, Sean; David, Bruno O.; McNiven, Ian J.; Asmussen, Brit; Tomkins, Helene; Dolby, Nic; Aplin, Ken; Richards, Thomas; Rowe, Cassandra; Leavesley, Matthew; Mandui, Herman (2013)

    Journal article
    University of Waikato

    The remains of shellfish dominate many coastal archaeological sites in the Pacific and provide a wealth of information about economy, culture, environment and climate. Shells are therefore the logical sample type to develop local and regional radiocarbon chronologies. The calibration of radiocarbon (¹⁴C) dates on marine animals is not straightforward, however, requiring an understanding of habitat and dietary preferences as well as detailed knowledge of local ocean conditions. The most complex situations occur where terrestrial influences impinge on the marine environment resulting in both the enrichment and depletion of ¹⁴C (Ulm Geoarchaeology 17(4):319–348, 2002; Petchey and Clark Quat Geochronol 6:539–549, 2011). A sampling protocol that combines a high-resolution excavation methodology, selection of short-lived samples identified to species level, and a tri-isotope approach using ¹⁴C, δ¹³C and δ¹⁸O, has given us the ability to identify ¹⁴C source variation that would otherwise have been obscured. Here, we present new research that details high-resolution mapping of marine 14C reservoir variation between Gafrarium tumidum, Gafrarium pectinatum, Anadara granosa, Anadara antiquata, Batissa violacea, Polymesoda erosa and Echinoidea from the Bogi 1 archaeological site, Caution Bay, southern coastal Papua New Guinea. These isotopes highlight specific dietary, habitat and behavioural variations that are key to obtaining chronological information from shell radiocarbon determinations.

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  • A 28,000 year old excavated painted rock from Nawarla Gabarnmang, northern Australia

    David, Bruno O.; Barker, Bryce; Petchey, Fiona; Delannoy, Jean-Jacques; Geneste, Jean-Michel; Rowe, Cassandra; Eccleston, Mark; Lamb, Lara; Whear, Ray (2013)

    Journal article
    University of Waikato

    We report new archaeological excavations from northern Australia revealing part of a charcoal design likely to be c. 28,000 years old (and chrono-stratigraphically constrained within the period 15,600-45,600 cal BP) on a small rock slab fallen from the ceiling at the rockshelter of Nawarla Gabarnmang in Jawoyn country, Arnhem Land. This represents the oldest confirmed pictograph in Australia.

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  • New radiocarbon dates from the Bapot-1 site in Saipan and Neolithic dispersal by stratified diffusion

    Clark, Geoffrey; Petchey, Fiona; Winter, Olaf; Carson, Mike; O’Day, Patrick (2010)

    Journal article
    University of Waikato

    The colonisation of the Mariana Islands in Western Micronesia is likely to represent an early ocean dispersal of more than 2000 km. Establishing the date of human arrival in the archipelago is important for modelling Neolithic expansion in Island Southeast Asia and the Pacific, particularly the role of long-distance dispersals. This paper presents new ¹⁴C results and a ΔR estimate from the Bapot-1 site on Saipan Island, which indicate human arrival at ca. 3400-3200 cal. BP. Archaeological chronologies of long-distance dispersal to Western Micronesia and the Lapita expansion (Bismarcks to Samoa) show that the Neolithic dispersal rate was increasing during the period ca. 3400-2900 cal. BP. The range-versus-time relationship is similar to stratified diffusion whereby a period of relatively slow expansion is succeeded by long-distance movement. An increase in new colonies created by long-distance migrants results in accelerating range expansion.

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  • Tongatapu hardwater: Investigation into the ¹⁴C marine reservoir offset in lagoon, reef and open ocean environments of a limestone island

    Petchey, Fiona; Clark, Geoffrey (2011)

    Journal article
    University of Waikato

    Although significant advances in our understanding of variation in the Pacific marine ¹⁴C reservoir have been made over the last ten years, our ability to obtain accurate calibrated ages for shellfish recovered from archaeological sites on Tongatapu remains problematic because of the influence of hardwaters on the central lagoon. Ultimately, this has implications for documenting the chronology of human movement and adaptation in this region. In this paper, we compare marine reservoir (∆R) data obtained from archaeological sites located along the lagoon and open coastline of Tongatapu, and use a combination of ∆R, δ¹⁸O and δ¹³C information to confirm a hardwater or open marine ¹⁴C signal in the shellfish. Despite documented changes to the lagoon as sea levels fell post-3000 years ago, these results indicate that there has been no noticeable change over time in the inner lagoon reservoir ¹⁴C value. Instead, variability in shellfish habitat and feeding modes is of greater concern to researchers using shell for dating, and requires further research

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  • Radiocarbon determinations from the Mulifanua Lapita site, Upolu, western Samoa

    Petchey, Fiona (2001)

    Journal article
    University of Waikato

    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 reassessment 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).

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  • New observations on the stratigraphy and radiocarbon dates at the Cross Creek site, Opito, Coromandel Peninsula

    Furey, Louise; Petchey, Fiona; Sewell, Brenda; Green, Roger (2008)

    Journal article
    University of Waikato

    This paper re-examines stratigraphy and radiocarbon dates at Cross Creek in Sarah's Gully. Three new radiocarbon dates are presented for Layer 9, the earliest, and previously undated, occupation. This investigation is part of a programme of archaeological work being carried out on the Coromandel Peninsula. Although there are several individual research projects underway, they have a common theme related to the Polynesian settlement period on the Coromandel Peninsula. The two seasons of excavation at Tairua are being written up by Matthew Campbell of CFG Heritage on behalf of Roger Green. Louise Furey, also CFG Heritage, is researching a thematic study on early sites for the Department of Conservation, Archaeological research in the Opito area includes documenting a pollen sequence for Opito under a grant obtained from the Green Foundation for Polynesian Research: Pam Chester, Louise Furey and Brenda Sewell are participants. In addition, positively identifying the Kaharoa Ash in the Opito-Sarah's Gully area is a priority.

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  • The excavation of Non Ban Jak, Northeast Thailand - A report on the first three seasons

    Higham, Charles; Cameron, Judith; Chang, Nigel; Castillo, Cristina; O'Reilly, Dougald; Petchey, Fiona; Shewan, Louise (2014)

    Journal article
    University of Waikato

    Non Ban Jak is a large, moated site located in the upper Mun Valley, Northeast Thailand. Excavations over three seasons in 2011-4 have revealed a sequence of occupation that covers the final stage of the local Iron Age. The site is enclosed by two broad moats and banks, and comprises an eastern and a western mound separated by a lower intervening area. The first season opened an 8 by 8 m square on the eastern mound, while the second and third seasons uncovered part of the low terrain rising into the western mound, encompassing an area of 25 by 10 m. The former revealed a sequence of industrial, residential and mortuary activity that involved the construction of houses, kiln firing of ceramic vessels and the interment of the dead within residences. The latter involved four phases of a late Iron Age cemetery, which again incorporated house floors and wall foundations, as well as further evidence for ceramic manufacture. The excavation sheds light on a late Iron Age town occupied at the threshold of state formation.

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  • Radiocarbon dating of burials from the Teouma Lapita cemetery, Efate, Vanuatu

    Petchey, Fiona; Spriggs, Matthew; Bedford, Stuart; Valentin, Frédérique; Buckley, Hallie (2014)

    Journal article
    University of Waikato

    The discovery of a cemetery at Teouma on the island of Efate in Vanuatu dated to c. 3000 years ago increased the number of early Pacific human remains available for study by nearly an order of magnitude and provided for the first time the ability to study the population dynamics of these early colonizers. The cemetery also provided an opportunity to investigate the chronological development of such a unique site. Although identified short-lived plant materials are favoured for dating archaeological sites, the reality of research in the Pacific region is that such materials are often rare, difficult to identify to species because of an absence of suitable reference collections, and dates on other materials often have greater potential to refine and focus ¹⁴C chronologies that deal with specific research questions. At Teouma, dates on the burial remains themselves are the best means to answer questions about the age and duration of the burial ground. Human bone, however, is one of the most complicated materials to date reliably because of dietary ¹⁴C offsets and bone preservation. One commonly used methodology for calibrating dates on human bone from Pacific human skeletal remains, based on linear interpolation between δ¹³C endpoints and δ¹⁵N values, is complicated by the wide range of foods available (marine, reef, C₄ and C₃), and remains largely untested in Pacific contexts. Radiocarbon dating of the Teouma site, including 36 Lapita-age burials, 5 dates on Conus sp. ring artefacts, and dates from the associated midden deposit, has enabled further evaluation of ¹⁴C dietary offsets and the reliability of calibrated radiocarbon ages on human bone. Bayesian evaluation of the ¹⁴C dates suggests the burial ground was in regular use by c. 2940-2880 cal BP, with the last interments occurring c. 2770-2710 cal BP. A number of burials could indicate possible earlier use, perhaps as early as 3110-2930 cal BP as indicated by the calibrated age range of Burial 57. This cannot be independently substantiated using other radiocarbon dates or context at the present time. Overall, these results suggest the burial ground was in use over a possible 150 to 240 years during the formative phase of Lapita expansion into Remote Oceania.

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  • The first accurate and precise calendar dating of New Zealand Māori Pā, using Otāhau Pā as a case study.

    Hogg, Alan G.; Gumbley, Warren; Boswijk, Gretel; Petchey, Fiona; Southon, John R.; Anderson, Atholl; Roa, Tom; Donaldson, Lloyd A. (2017)

    Journal article
    University of Waikato

    This research investigates the potential of radiocarbon wiggle-match dating of palisade posts to provide precise and accurate calendar ages for Māori pā (forts), using Otāhau Pā in the inland Waikato region, New Zealand, as a case study. Even though pā are a dominant element of the pre-European North Island archaeological landscape, they are poorly understood archaeologically, with systematic investigations hampered by the relative lack of precision in radiocarbon dating within the context of New Zealand’s comparatively short prehistory. Using the Southern Hemisphere calibration curve SHCal13, we determine wiggle-match calibrated ages for three palisade posts, using different sampling resolutions to determine the cost- effectiveness of the method. We also test the accuracy of the wiggle-match by obtaining new Southern Hemisphere calibration data from known calendar-age kauri.

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  • Earliest evidence for ground-edge axes: 35,400±410 cal BP from Jawoyn Country, Arnhem Land

    Geneste, Jean-Michel; David, Bruno O.; Plisson, Hugues; Clarkson, Chris; Delannoy, Jean-Jacques; Petchey, Fiona; Whear, Ray (2010)

    Journal article
    University of Waikato

    Evidence for the world’s earliest stone tools dates to 3.4 million years ago and pre-dates the earliest known Homo species in eastern Africa. However ground-edged tools did not appear until the dispersal of cognitively fully modern Homo sapiens sapiens out of Africa. We report on the discovery of the earliest securely dated ground-edge implement in the world at Nawarla Gabarnmang (northern Australia). The fragment of ground-edge axe is sandwiched between four statistically indistinguishable AMS radiocarbon dates of 35,400±410 cal BP, indicating technological innovations by fully modern Homo sapiens sapiens at the eastern end of the Out-of-Africa 2 Southern Arc dispersal route.

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  • Djadjiling Rockshelter: 35,000 ¹⁴C Years of Aboriginal Occupation in the Pilbara, Western Australia

    Law, W. Boone; Cropper, Dawn N.; Petchey, Fiona (2010)

    Journal article
    University of Waikato

    The Pleistocene settlement of the arid zone is a prominent research theme in Australian archaeology (Hiscock 2008:45- 62; Hiscock and Wallis 2004; Marwick 2002a, 2002b; O’Connor et al. 1998; Smith 1987, 2005; Thorley 1998; Veth 1993, 1995, 2005). Of particular interest is the inland Pilbara region of the western arid zone, which until recently was reported to have been first occupied between c.20,000 BP and c.26,000 BP (Brown 1987:27; Edwards and Murphy 2003:45; Maynard 1980:7). The recent test excavations at Juukan-1 rockshelter suggest the region was occupied before 32,920±270 BP (Slack et al. 2009:34). Our research at Djadjiling rockshelter supports this result by demonstrating an Aboriginal presence at the site c.35,000 years ago. Not only is the site unique for its antiquity, but excavations have recovered a large flaked stone assemblage from the earliest occupational phase. The evidence demonstrates repeated early site use, and a sequence of intermittent occupation throughout the late Pleistocene and Holocene. The preliminary findings are presented below.

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  • Marine Reservoir variation in the Bismarck Region: An evaluation of spatial and temporal change in ∆R and R over the last 3000 years

    Petchey, Fiona; Ulm, Sean (2012)

    Journal article
    University of Waikato

    Interactions between islands, ocean currents, and winds cause large-scale eddies and upwelling in the lee of islands that can result in spatial variation in the marine radiocarbon reservoir. For waters around New Ireland and the Bismarck Sea, ∆R values ranging from 365 to –320 14C yr have been reported (Kirch 2001; Petchey et al. 2004). Petchey et al. (2004) proposed that some of this variation was caused by seasonal reversals in the South Equatorial Current and North Equatorial Counter Current system, combined with Ekman upwelling from the Equator. McGregor et al. (2008) suggested additional complexity within this region caused by a change in the reservoir value over time in response to changing climatic conditions. We present a series of 14 new and extant published ∆R and R values on historic shells, combined with 8 values from archaeological terrestrial/marine pairs and U-Th dated coral, that support observations of localized variability caused by a complex interplay between seasonal currents, riverine input, and ocean eddies. On the basis of these values and oceanographic data, we divide the Bismarck Sea surface marine 14C reservoir into 6 tentative subregions. In particular, our results support significant variation within channels at the southwest and southeast ends of New Britain and towards the equatorial boundary of the sea. Our results indicate that within the Bismarck Sea geographical variation appears to be more extreme than temporal over the last 3000 yr.

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  • New Marine ΔR values for the South Pacific subtropical gyre region

    Petchey, Fiona; Anderson, Atholl; Zondervan, Albert; Ulm, Sean; Hogg, Alan G. (2008)

    Journal article
    University of Waikato

    This paper presents 31 new ΔR results of known-age, pre-AD 1950 shells from the South Pacific subtropical gyre region, spanning from the Tuamotu Archipelago in the east to New Caledonia in the west. This doubles the number of available ΔR values for the Oceania region. These values indicate that the regional offset (ΔR) from the modeled radiocarbon marine age has remained relatively constant over the last 100 yr prior to 1950. Variation from the norm can be attributed to various influences including localized upwelling around islands, the presence of a hardwater effect, direct ingestion of old carbon by the live shellfish, or enhanced exchange with atmospheric CO2 as a consequence of photosynthetic activity or increased aeration.

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