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301.
This paper describes an analysis to validate the effective hydration temperature (EHT) algorithm for obsidian [Rogers, A.K., 2007. Effective hydration temperature of obsidian: a diffusion-theory analysis of time-dependent hydration rates. J. Arch. Sci. 34, 656-665], using hourly temperature data from the Amargosa Desert Research Site near Beatty, NV. These data were used as input to a numerical model of the temperature-dependent diffusion process, and EHT was calculated yearly and for the aggregate. The same temperature data were processed to extract input parameters for the climatic model reported and used as input for EHT computation. EHT as computed from recorded hourly data was found to be within 1 °C of that computed from the climatic model. It is also shown that computed EHT differences between sites are not sensitive to whether air or surface temperature data are used, as long as they are used consistently; however, surface temperature data must be used if depth corrections are to be made. 相似文献
302.
David G. Beresford-Jones Katherine Johnson Alexander G. Pullen Alexander J.E. Pryor Jiří Svoboda Martin K. Jones 《Journal of archaeological science》2010
This paper compares archaeobotanical and other data from new excavations at two Upper Palaeolithic sites — Dolní V?stonice II and P?edmostí I — in the Moravian Corridor, Czech Republic. Both contain the traces of broadly contemporary ‘Gravettian’ occupations during the warmer episodes of the Pleistocene which preceded the last glacial maximum. Yet their archaeobotanical remains show striking differences — those from Dolní V?stonice II being dominated by large quantities of conifer wood charcoal, while those from P?edmostí I are much more scanty and dominated by vitrified plant remains, in association with large quantities of burnt bone. We argue that these differences between these two datasets arise from different uses of fuel at either site: bone at P?edmostí I and wood at Dolní V?stonice II. Subsequently, we explore the possible reasons for this difference and argue that once likely taphonomic distinctions are accounted for, these data on fuel use offer fresh insights into the functions and durations of these Upper Palaeolithic occupations of the Moravian corridor and some possible implications for how archaeobotanical data from such sites should be interpreted. 相似文献
303.
Lorna T. Corr Michael P. Richards Susan Jim Stanley H. Ambrose Alexander Mackie Owen Beattie Richard P. Evershed 《Journal of archaeological science》2008
The remains of the preserved ice body from the Kwäd?y Dän Ts'ìnch? discovery were recovered from a retreating glacier in the Tatshenshini-Alsek Park, British Columbia in August 1999. Despite the remote location 80 km inland, bone collagen stable isotope analysis indicated that the individual spent much of his life in a region rich in marine foods (δ13C −13.7‰ and δ15N +17.9‰). Since finds of such bodies are exceptionally rare we undertook detailed lipid analyses in order to assess their preservation and determine whether they might provide new insights into the individual’s dietary life history. Molecular fingerprinting and compound-specific carbon isotope analysis were performed on individual lipids extracted from his bone (turnover approximately ≥1 year) and skin (turnover approximately several weeks). A considerable abundance was observed of C12:0, C14:0, C16:0, C16:1, C18:0 and C18:1 fatty acids (FAs), cholesterol and hydroxy FAs (the latter being decay products). Most unusual was the presence of long-chain hydroxy FAs (LCHFAs), 10- and 12-hydroxyeicosanoic acid and 10- and 12-hydroxydocosanoic acid, in the bone. The latter components are most likely the products of microbially mediated hydration of the double-bonds of C20:1 and C22:1 FAs, the latter almost certainly originating from the consumption of a largely marine-based diet. A suite of three isoprenoidal lipids, phytanic acid, pristanic acid and 4,8,12-trimethyltetradecanoic (TMTD) acid, was also detected supporting the notion of a significant marine component of the diet for a substantial part of his life. In contrast, the skin lipid composition was dominated by C16:0 FA, with lower abundances being observed of the marine LCHFAs and isoprenoidal compounds, suggesting reduced reliance on coastal marine foods in the last period of life. This interpretation is supported by the enhanced marine dietary signal observed in the bone than skin FA δ13C values. 相似文献
304.
Zerina Johanson Alexander Ritchie 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):99-118
A new genus and species of lungfish with toothplates, Adelargo schultzei, is described from the Hunter Siltstone (Devonian, Late Famennian) near Grenfell, New South Wales. Materials assigned to Adelargo schultzei gen. et sp. nov., include a portion of the left side of the skull comprising B, I (postparietal) and J (parietal) bones, pterygoid and prearticular toothplates, a parasphenoid with a long posterior stalk, vertebrae, ribs, anal fin supports and scales. Toothplates are similar to Dipterus, although morphology of the skull, parasphenoid and postcranial elements is more derived. Biogeographic relationships of the Grenfell fauna were based on the presence of the antiarch group Sinolepidoidei, also present on Asian terranes during the Late Devonian. A small number of lungfish scales have been described from Asian sinolepid localities of this age, but differ from those of Adelargo schultzei, and other faunal similarities between these areas appear limited. Paucity of eastern Australian Devonian taxa on the North and South China blocks implies that strong biogeographic relationships between eastern Australia and Euramerican localities during the Late Devonian were not the result of Asian migration routes, but the closer proximity of these areas. 相似文献
305.
Robert J. Alexander 《历史新书评论》2013,41(4):158-159
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