• Editorial Board

      McClure, Mark (Department of Geosciences, The University of Arizona, 2012-05-04)
    • Historic Lime-Mortar Radiocarbon Dating of Santa María la Real (Zarautz, Northern Spain): Extraction of Suitable Grain Size for Reliable 14C Dating

      Ortega, Luis Angel; Zuluaga, Maria Cruz; Alonso-Olazabal, Ainhoa; Murelaga, Xabier; Insausti, Maite; Ibañez-Etxeberria, Alex (Department of Geosciences, The University of Arizona, 2012-05-04)
      This paper describes a method for effective separation of the pure binder fraction of lime mortars for reliable radiocarbon dating. The methodology allows removal of the detrital carbonate fraction and the unburnt limestone particles, obtaining particles of under 1 µm. The extracted fraction ensured that all carbonate has been generated by slaked lime carbonation. Consequently, the measured carbon corresponds to atmospheric carbon. The proposed method allows to obtain pure datable binder, simplifying considerably the performance of radiometric measurements because dating other grain-size fraction is unnecessary. In order to prove the effectiveness of binder refining, the extraction method has been applied to 5 lime mortars of different archaeological periods from the perimeter walls of Santa María la Real parish church (Zarautz, northern Spain).
    • 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 (Department of Geosciences, The University of Arizona, 2012-05-04)
      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.
    • Measurement of 10Be Concentration of Modern Falling Dust in Northern China

      Xian, Feng; Zhou, Weijian; Kong, Xianghui; Jiang, Jun; Wu, Zhenkun; Chen, Ning; Zhao, Guoqing (Department of Geosciences, The University of Arizona, 2012-05-04)
      Paleoenvironmental and paleogeomagnetic tracing studies from Chinese loess 10Be have progressed in recent years (Zhou et al. 2007a,b, 2010). In this approach, 10Be flux determined from sediment concentration and accumulation rate may be used to recover information about paleomonsoon rainfall rates as well as past variations in the geomagnetic field strength. However, these methods require that a correction be made for residual undecayed 10Be in remobilized dust. To better understand the feature of the 10Be signals related to the remobilized dust, we report the first observational study on 10Be concentration of modern falling dust using the 3MV multi-element accelerator mass spectrometer (AMS) in the Xi’an AMS Center. Ten samples collected at Ansai observation station (109°19'E, 36°51'N) in northern China from May 2008 to June 2009 are measured along with 3 chemical blanks. The results clearly show that the 10Be content of modern falling dust is relatively uniform, with a mean value of 1.21 × 10sup8/sup atoms/g, a measurement similar to that of Chinese loess (Zhou et al. 2007a) and to the value found in the study by Shen et al. (2009) on dust 10Be falling near Dingbian, China (1.25 ± 0.06 × 10sup8/sup atoms/g). Despite the fact that modern dust flux is much higher in spring relative to summer in northern China, 10Be concentration in falling dust remains fairly constant. In addition, we find that dust 10Be concentration is roughly independent of the local precipitation changes. This feature might be considered as an analogue to improve our understanding on the fundamental information of the source component contained in loess 10Be records and its spatial/temporal distribution features.
    • Mid-Holocene Dates for Organic-Rich Sediment, Palustrine Shell, and Charcoal from Southern Iraq

      Hritz, Carrie; Pournelle, Jennifer; Smith, Jennifer; Albadran, Badir; Majeed Issa, Bushra; Al-Handal, Adil (Department of Geosciences, The University of Arizona, 2012-05-04)
      We present the results of accelerator mass spectrometry (AMS) radiocarbon dating of 11 samples collected from 4 locations in southern Iraq. As a result of the hiatus in fieldwork in that region since 1990, and the antiquity of the majority of archaeological excavations conducted there, the record of 14C dates for southern Mesopotamia is patchy for all periods. This is especially true for the mid-Holocene, when the world’s oldest and longest-sustained urban system first emerged there. The dates here reported not only make a significant contribution to available dates for this important region and period; they fill specific gaps in crucial geographic coverage, and shed light on the extent of marshland boundaries and the antiquity of settlement at key urban centers.
    • Obituary: Johann Carl Vogel (1932-2012)

      Talma, Siep; Visser, Ebbie; Fuls, Annemarie; Mook, Wim; van der Plicht, Hans (Department of Geosciences, The University of Arizona, 2012-05-04)
    • Obituary: Leopold Dmitrievich Sulerzhitsky (1929-2012)

      Pokrovsky, B. G.; Pevzner, M. M.; Zaretskaya, N. E.; Kuzmin, Y.; Ineshin, E. (Department of Geosciences, The University of Arizona, 2012-05-04)
    • Radiocarbon and Stable Carbon Isotopes in Two Soil Profiles from Northeast India

      Laskar, Amzad H.; Yadava, M. G.; Ramesh, R. (Department of Geosciences, The University of Arizona, 2012-05-04)
      Two soil profiles from northeast India, one from Bakrihawar, an agricultural land, and the other from Chandipur, a virgin hilly area from Assam, are investigated to understand the organic carbon dynamics of the area. Due to frequent flooding, the Bakrihawar soil has accumulated a higher clay content than that of Chandipur. The carbon content is less than 1% by weight in both the sites. The higher clay content is responsible for relatively more soil organic carbon at Bakrihawar. The mean δ13C values at both sites reflect the values of the overlying vegetation. At Bakrihawar, both rice cultivation (C3) and natural C4 grasses contribute to higher mean enriched values of 13C relative to Chandipur, where the surface vegetation is mostly of C3 type. The turnover time of organic carbon, estimated using the residual radiocarbon content, depends strongly on the soil particle size distribution, especially the clay content (i.e. it increases with clay content). To the best of our knowledge, this is the first soil carbon dynamics study of its kind from northeast India.
    • Radiocarbon Dates from Jar and Coffin Burials of the Cardamom Mountains Reveal a Previously Unrecorded Mortuary Ritual in Cambodia’s Late- to Post-Angkor Period (15th–17th Centuries AD)

      Beavan, Nancy; Halcrow, Sian; McFadgen, Bruce; Hamilton, Derek; Buckley, Brendan; Sokha, Tep; Shewan, Louise; Sokha, Ouk; Fallon, Stewart; Miksic, John; et al. (Department of Geosciences, The University of Arizona, 2012-05-04)
      We present the first radiocarbon dates from previously unrecorded, secondary burials in the Cardamom Mountains, Cambodia. The mortuary ritual incorporates nautical tradeware ceramic jars and log coffins fashioned from locally harvested trees as burial containers, which were set out on exposed rock ledges at 10 sites in the eastern Cardamom Massif. The suite of 28 14C ages from 4 of these sites (Khnorng Sroal, Phnom Pel, Damnak Samdech, and Khnang Tathan) provides the first estimation of the overall time depth of the practice. The most reliable calendar date ranges from the 4 sites reveals a highland burial ritual unrelated to lowland Khmer culture that was practiced from cal AD 1395 to 1650. The time period is concurrent with the 15th century decline of Angkor as the capital of the Khmer kingdom and its demise about AD 1432, and the subsequent shift of power to new Mekong trade ports such as Phnom Penh, Udong, and Lovek. We discuss the Cardamom ritual relative to known funerary rituals of the pre- to post-Angkorian periods, and to similar exposed jar and coffin burial rituals in Mainland and Island Southeast Asia.
    • Radiocarbon Dating of Pleistocene Fauna and Flora from Starunia, SW Ukraine

      Kuc, Tadeusz; Różański, Kazimierz; Kotarba, Maciej J.; Goslar, Tomasz; Kubiak, Henryk (Department of Geosciences, The University of Arizona, 2012-05-04)
      New attempts are presented to determine the age of large Pleistocene mammals excavated at Starunia, ~130 km southeast of Lviv, Ukraine. This remarkable discovery made at the beginning of the 20th century included a complete carcass of woolly rhinoceros (No. 2), fragments of 3 woolly rhinoceroses (Nos. 1, 3, and 4) and remnants of numerous specimens of other fossil fauna and flora. Although attempts to date paleontological findings from Starunia site go back to the early 1970s, the results obtained before 2006 are somewhat misleading, mostly due to unresolved contamination problems. Comprehensive cleaning of the samples adopted in the framework of this study was aimed at removal of 2 potential sources of contamination: (i) radiocarbon-free hydrocarbons abundant at the burial site; and (ii) allochthonous organic materials containing contemporary carbon that were used in the past during preservation of the dated specimens. Two types of samples have been analyzed for their 14C content in the framework of the present study: (i) fragments of bones and teeth collected from specimens stored or exposed in the Natural History museums in Lviv and Kraków; and (ii) samples of terrestrial macrofossils retrieved from sediment cores obtained during the 2007–2008 field campaigns in the Starunia area. 14C analyses of collagen were supplemented by measurements of its elemental C/N ratio and 13C/12C and 15N/14N isotope ratios. Three 14C dates obtained for rhinoceros No. 2 span the age range from 35.3 to 40.0 ka BP, in agreement with the minimum age estimated from macrofossils. The mean value of 37.7 ± 1.7 ka BP falls in the range of ages reported for big Pleistocene mammals from other locations in Europe. The bones of rhinoceros No. 3, which were found in close vicinity to those of rhinoceros No. 2, reveal a 14C age of 36.7 ± 0.6 ka BP. The δ15N and δ13C values obtained for collagen extracted from bones and teeth belonging to rhinoceroses Nos. 1, 2, and 3 are in a broad agreement with analogous literature data for large Pleistocene mammals found in other sites in Europe, North America, and Siberia.
    • Re-Examining Anomalous Early Dates of Settlement in Leeward Hawai‘i Island

      Carson, Mike T. (Department of Geosciences, The University of Arizona, 2012-05-04)
      Anomalous dates prior to 1000 yr BP have been reported for near-surface site deposits at Puapua‘a in the dry and rocky zone of leeward (west) Hawai‘i Island, compared to archipelago-wide earliest cultural layers generally in buried contexts 1000–800 yr BP. Redating and closer examination cannot validate these early dates in cultural association. In the thin sedimentary deposits, preserved cultural materials mostly postdate 600–400 yr BP, but some older materials were incorporated into the layer matrix. The results suggest a much shorter extant chronology of human settlement of this particular zone, whereas earliest sites most likely are preserved in different settings of the Hawaiian Islands.
    • Rudjer Bošković Institute Radiocarbon Measurements XVII

      Horvatinčić, Nada; Krajcar Bronić, Ines; Obelić, Bogomil; Barešić, Jadranka (Department of Geosciences, The University of Arizona, 2012-05-04)
      This paper presents dating results of geological (speleothems, tufa, soil, and sediment), biological (mollusks and botanical), as well as hydrogeological samples from Croatia, Slovenia, Bosnia and Herzegovina, Turkey, and China. Included are results of samples measured by gas proportional counting (GPC) in the Zagreb lab until abandonment of this technique in 2007, as well as results of several series measured by both GPC and liquid scintillation counting (LSC) methods.
    • Table of Contents

      McClure, Mark (Department of Geosciences, The University of Arizona, 2012-05-04)