668 research outputs found
Chemical and oxygen isotopic composition of Roman and late Antique glass from northern Greece
The present paper emphasizes the importance of measuring the oxygen isotopic and chemical compositions of ancient glass, in
order to constrain some features such as age, raw materials, and production technologies and to identify the \u201cfingerprint\u201d of local
productions. In this context, thirty-nine Roman and late Antique glass samples and eight chert samples fromnorthern Greece were
selected and analysed for their oxygen isotopic and chemical compositions. Results show that the majority of glass samples are
produced using natron as flux and have 18O values of about 15.5\u2030, plus or minus a few tenths of one per mil, suggesting that raw
materials probably come from Levantine area. Four samples are heavily enriched in 18O, and their chemical composition clearly
shows that they were made with soda plant ash as flux. Isotopic and chemical data of Greek chert samples support the hypothesis
of local production of the above samples. About half of the glass samples have chemical compositions, which allow their age to be
constrained to the late Antique period. For the remaining glass, similarities with literature compositional groups are reported and
discussed
Oxygen Isotope Analysis of Human Bone Phosphate Evidences Weaning Age in Archaeological Populations
Acknowledgements With special thanks to Jean-Jacques Hublin and the MPI-EVA; to Annabell Reiner (MPI-EVA) and Bernd Steinhilber (Universitat Tubingen) for technical support;and to the Deutscher Akademischer Austausch Dienst for financial support to KB during this project (ref: A0970923). This research was funded by the Max Planck Society. TT was financed by the DFG Emmy Noether Program and acknowledges funding by the grant TU 148/2-1 for the Emmy Noether Group Bone Geochemistry. Thanks also tothe University of Aberdeen for support during the preparation of this manuscript.Peer reviewedPostprin
Ricostruzione paleoclimatica attraverso l'analisi di uno speleotema nella Sardegna centro-orientale: risultati preliminari
This paper, carried out in the framework of a local project 60% «Pleistocene-Holocene palaeoclimate and palaeogeography reconstructions based on marine and continental deposits of Sardinia» (Resp. Prof. Sandro De Muro) and within a series of researches involving several bodies (Archaeological Superintendence of NU/SS, Universities of Parma and Cagliari) and caving associations (Gruppo Speleo Ambientale
Sassari, Gruppo Speleo-Archeologico Giovanni Spano of Cagliari, Unione
Speleologica Cagliaritana and Gruppo Archeo Speleo Ambientale Urzulei), reports the
first results of a palaeo-climate study carried out on a stalagmite sampled in the Su Palu
cave, Codula Ilune, Urzulei (Central-East Sardinia). This stalagmite has been subjected
to radiometric U/Th dating and stable isotope δ180 and δ 13C analysis. These isotopic
data based on 139 samples showed a general increase in stable isotope ratios that would
indicate a growth of the concretion in a period of global warming (Upper Pleistocene-
Holocene?). The chronological setting by means of U/Th datings, unfortunately, did not
allow to define the exact timeframe because of the presence of detrital Thorium. C14
analysis are under way to try to obtain information on the time during which the
stalagmite growed
Isotopic characteristics of the Garonne River and its tributaries
The Garonne is the largest river in the south-west of France, and its drainage basin stretches between
the Pyrenees and the Massif Central mountains. Until now, no water stable isotope study has been
performed on the whole Garonne river basin which is composed of different geological substrata,
and where the water resources are limited during the dry summer period. This study focuses on the
Garonne river and its tributaries from the Pyre´ne´es foothill upstream to its confluence with the Lot
River downstream. The aim of the study is to determine the origins of the surface waters using their
chemical and stable isotopic compositions (18O, D and 13C), to better understand their circulation
within the drainage basin and to assess the anthropogenic influences. The Garonne displays a
specific 18O seasonal effect, and keeps its Pyre´nean characteristics until its confluence with the Tarn
River. The difference in the dissolved inorganic carbon (DIC) comes mainly from the change in
lithology between the Pyre´ne´es and the Massif Central mountains. Agriculture activity is only
detected in the small tributaries
Air Masses Origin and Isotopic Tracers: A Study Case of the Oceanic and Mediterranean Rainfall Southwest of France
Aquifers recharge mainly by local rainfall, which depend on the air mass humidity and orographic lifting, causing rain. The stable isotopes of the water molecule, i.e., oxygen-18 and deuterium, are useful tracers to determine the water source origin. Moreover, the calculation of the deuterium excess enables one to differentiate between the air masses from the Atlantic Ocean or the Mediterranean Sea. A transect from one coast to the other one and going through the city of Toulouse have been made to sample the groundwater and determine their isotopic characteristic. A monthly rainfall sampling has also been done over one year, close to the city Toulouse, to see how the d-excess values range over the season. The discussion replaces these results in available isotopic data
Kimmeridgian-Tithonian sea-level fluctuations in the Uljanovsk-Saratov Basin (Russian Platform)
Abstract
The Uljanovsk-Saratov Basin, located in the southeast of the Russian Platform, presents an intriguing record of the Kimmeridgian-Tithonian sea-level fluctuations. In the Late Jurassic, this basin was a trough within the Interior Russian Sea. The data available from both outcrops and boreholes have permitted outlining a number of lithostratigraphic units and regional hiatuses in the northeastern segment of the Uljanovsk-Saratov Basin, thus permitting a precise reconstruction of transgressions/regressions and deepenings/shallowings. In total, three transgressive-regressive cycles and two deepening pulses have been established. These regionally documented changes were both related in part to global eustatic changes, and they also corresponded in part to the regional sea-level changes in some basins of Western Europe and Northern Africa, but not to those of the Arabian Platform. Differences observed between the global and regional curves as well as rapid Tithonian sea-level oscillations are explained by the influences of tectonic activity. It is hypothesized that the regional Tithonian oxygen depletion might have been a consequence from the rapid flooding of a densely vegetated land
Diversity in pig husbandry from the Classical-Hellenistic to the Byzantine periods: an integrated dental analysis of Düzen Tepe and Sagalassos assemblages (Turkey)
Ethnographical, historical and archaeological evidence suggests that a great diversity in pig husbandry may have
existed in the past. However, such diversity remains difficult to document from traditional zooarchaeological
methods and its study may necessitate the implementation of combined methodological approaches. An integrated
dental analysis, combining kill-off patterns, traditional and geometric morphometrics, linear enamel hypoplasia
(LEH), microwear and stable isotope (δ18O,δ13C, δ15N) data, has been performed on assemblages from the neighbouring sites of Düzen Tepe and Sagalassos (SW Turkey) dated to Classical-Hellenistic to Byzantine
time periods. Results indicate a diachronic evolution in slaughter practices, and a gradual decrease in pig mean
size from the Early-Middle Imperial to the Byzantine. The seasonality of physiological stressing events remains
the same, although their intensity varies through time. During the Early Byzantine period (CE 450–700), pig demographic management is characterized by two birth seasons, and a great diversity in diet and scale of management occurred, from free-ranging pigs – whether or not given food supplement - to closely confined wellwatered and more omnivorous pigs
Atmospheric CO 2 concentrations and δ 13 C values between New Zealand and Antarctica, 1998 to 2010: some puzzling results
From 1998 to 2010, during eight cruises of the M/V Italica between New Zealand and Antarctica, sets of flask air samples were collected and atmospheric CO 2 concentrations were recorded. The δ 13 C of CO 2 from the 1998 to 2003 air samples have already been published and show large interannual variability and an increasing frequency of 13 C-depleted samples. These results were related to a mosaic of areas with positive air–sea fluxes. We report here δ 13 C results from air samples collected from four further cruises. δ 13 C values obtained during the 2004/2005 cruise show an inexplicable saw-toothed distribution. Air samples from the 2005/2006 cruise have δ 13 C values which match previous sets of samples (1998 to 2004) and show more frequent and more negative isotopic events. From 2006 until 2009, further samples could not be collected. However, during December 2009 and January 2010, two more sets of air samples were collected, the δ 13 C values of which greatly differ from previous results, being absolutely homogeneous and paralleled by flat CO 2 concentrations. The results of these last two sets of air samples may be due either to fortuitous environmental conditions or to an improbable and substantial change in oceanic and atmospheric conditions in this section of the circumpolar area. Keywords: New Zealand to Antarctica, flask air samples, atmospheric CO 2 concentrations, carbon isotopic composition of CO 2 , puzzling results (Published: 5 December 2012) Citation: Tellus B 2012, 64 , 17472, http://dx.doi.org/10.3402/tellusb.v64i0.1747
Paleoclimatic and paleobiological correlations by mammal faunas from Southern America and SW Europe
Proceedings of the 1" R.C.A.N.S. Congress, Lisboa, October 1992The preliminary results of a research dealing with the study of global changes in the last 5 Ma by correlations of continental records between the Northern and the Southern Hemispheres (SW Europe and Argentina, respectively) are reported. The first analyses of the evolutionary patterns point out, in Argentina, two different turnover times: the first one is characterized by a high percentage of
mammalautochthonous extinctions placed in the span of time between the last Chapadmalalan and the first Ensenadan faunas, around 2.5-2.3 Ma. It is possible to identify a high percentage of new immigrant genera from North America in the first turnover, while the second one, associated to the "last Pleistocene megafaunal extinctions", probably occurred at the beginning of the "Glacial Pleistocene", around 1.0-0.8 Ma. The oxygen isotope composition of phosphate from fossil mammal bones was measured to have a better climatic resolution from faunal elements of two hemispheres and to compare them by results as quantitative as possible. The preliminary efforts are brought out on fourteen deposits from SE Spain. Isotopic and chemical results strongly suggest the existence of a relation between the oxygen isotope composition in various skeletal components and the taphonomic processes of a single deposit. The variations of 0180 in the mammal teeth of Equidae from SE Spain suggest a shift towards a colder environment from the older one, Huelago, to more recent deposits, as well as from Venta Micena to Fuensanta in agreement with the transition from the Middle to the Upper Villafranchian, around 2.5 Ma, and the transition between the "Preglacial" to the "Glacial" Pleistocene, around 1.9-0.8 Ma
Bone stable isotopic signatures (15N, 18O) as tracers of temperature variation during the Late-glacial and early Holocene: case study on red deer Cervus elaphus from Rochedane (Jura, France)
International audienceStable isotopes in mammal bones are mainly used to reconstruct dietary preferences and their use as palaeoclimatic indicators is less developed. However, important variations in 15N abundances observed in the bone collagen of large mammals during the Late-glacial and early Holocene have been tentatively linked to a general increase in temperature. In order to test this hypothesis, we analysed nitrogen and oxygen isotopic abundances from bones of red deer (Cervus elaphus) from the Rochedane site (Jura, France). We observe a clear linear relationship between 15N and 18O that demonstrates the effect of temperature on the abundance of 15N in red deer bone collagen. These results suggest that an increase in soil maturation during global warming of the Late-glacial and early Holocene led to an increase of 15N in soils and plants that was passed on to their consumers. Red deer seem to be particularly suited for palaeoclimatic reconstruction based on the isotopic signatures of their bone
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