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Jan Veizer - One of the best experts on this subject based on the ideXlab platform.
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weathering processes in the indus river basin implications from riverine carbon sulfur oxygen and Strontium Isotopes
Chemical Geology, 2000Co-Authors: Ajaz Karim, Jan VeizerAbstract:Abstract This study deals with the major ions and isotope systematics for C, O, S, and Sr in the Indus River Basin (IRB). Major ion chemistry of the Indus, and most of its headwater tributaries, follow the order Ca2+>Mg2+>(Na++K+) and HCO3−>(SO42−+Cl−)>Si. In the lowland tributaries and in some of the Punjab rivers, however, (Na++K+) and (SO42−+Cl−) predominate. Cyclic salts, important locally for Na+ in dilute headwater tributaries, constitute about 5% of the annual solutes transported by the Indus. Weathering of two lithologies, sedimentary carbonates and crystalline rocks, controls the dissolved inorganic carbon (DIC) concentrations and its carbon isotope systematics throughout the Indus, but turbulent flow and lower temperatures in the headwaters, and storage in reservoirs in the middle and lower Indus promote some equlibration with atmospheric carbon dioxide. Combined evidence from sulfur and oxygen isotopic composition of sulfates refutes the proposition that dissolution of these minerals plays a significant role in the IRB hydrochemistry and suggests that any dissolved sulfates were derived by oxidation of sulfide minerals. In the upper Indus, silicate weathering contributes as much as 75% (or even higher in some tributaries) of the total Na+ and K+, declining to less than 40% as the Indus exits the orogen. In contrast, about two-thirds of Ca2+ and Mg2+ in the upper Indus (over 70% in some tributaries) and three-fourth in the lower Indus, are derived from sedimentary carbonates. The 87Sr/86Sr ratios tend to rise with increasing proportions of silicate derived cations in the headwater tributaries and in the upper and middle Indus, but are out of phase or reversed in the lower Indus. Finally, close to the river mouth, the discharge weighted average contribution of silicate derived Ca2++Mg2+ and silicate derived Na++K+ are, respectively, about one-fourth and two-thirds of their total concentrations.
T. Douglas Price - One of the best experts on this subject based on the ideXlab platform.
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Strontium Isotopes and the Study of Human Mobility Among the Ancient Maya
Archaeology and Bioarchaeology of Population Movement among the Prehispanic Maya, 2014Co-Authors: T. Douglas Price, James H. Burton, Paul D. Fullagar, Lori E. Wright, Jane E. Buikstra, Vera TieslerAbstract:The present chapter on Strontium Isotopes from human dental enamel aims at presenting four archaeological case studies to illustrate the anthropological significance and range of applications of this technique: a northern Maya origin for the founder of Copan, a local king from Tikal, and the regional origin of two of Palenque’s rulers. The results show that isotopic variation within the various culturally important regions of Mesoamerica is generally much less than variation among the different regions. Thus analysis of Strontium isotope ratios in dental enamel, which retains the ratio of the place of childhood residence, can be used not only to indicate mobility but also on occasion to determine the geographic origin of the individual.
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Strontium Isotopes and human mobility in prehistoric Denmark
Archaeological and Anthropological Sciences, 2012Co-Authors: Karin Margarita Frei, T. Douglas PriceAbstract:The principles behind the Strontium isotopic system are an important tool for archaeologists tracing human migration and patterns of movement in prehistory. However, there are several scientific challenges of analytical nature, as well as those which relate to unknown parameters inherent to the interpretation of such data. One prerequisite is the knowledge of the range of Strontium isotopic ratios that best characterize the bioavailable fractions of a particular area of interest. The study reported here attempts to establish a baseline for Strontium isotope signatures valuable for Denmark (excluding the island of Bornholm) and particularly for the use in archaeological investigations. We present Strontium isotope ratios of bones and teeth from modern mice contained in owl pellets, of snail shells, and of archaeological fauna samples. We compare these ratios with median Strontium isotope signatures characterizing human enamel populations from archaeological sites within Denmark. The fauna samples reported here range from ^87Sr/^86Sr = 0.70717 to 0.71185 with an average of 0.70919, and human enamel defines a range from ^87Sr/^86Sr = 0.7086 to 0.7110 with an average of 0.7098. In both datasets, we observe a small difference between the baseline values for the western (Jutland) and eastern (Funen, Zealand, and the southern islands) parts of Denmark. We therefore propose two slightly different baseline ranges with a partial overlap for the isotopic signatures of bioavailable Strontium fractions within Denmark, namely a range of ^87Sr/^86Sr = 0.7078–0.7098 for the western area and a range of ^87Sr/^86Sr = 0.7089–0.7108 for the eastern parts.
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Strontium Isotopes and the study of human mobility in ancient Mesoamerica
Latin American Antiquity, 2008Co-Authors: T. Douglas Price, James H. Burton, Paul D. Fullagar, Lori E. Wright, Jane E. Buikstra, Vera TieslerAbstract:We analyzed Strontium Isotopes in more than 500 samples of shell, bone, and dental enamel from modern and archaeological contexts throughout Mesoamerica. The results correspond closely with expectations based upon the local geology and earlier measurements of geological materials. The results show that isotopic variation is significant across Mesoamerica. Thus Strontium isotope ratios in dental enamel, which mark the place of childhood residence, can be used not only to document mobility but also in some cases to determine geographic origin. We present five archaeological case studies to illustrate the anthropological significance and range of applications for this technique: the origins of individuals in the "Oaxaca Barrio" at Teotihuacan, a northern origin for the founder of Copan, a local king at Tikal, the regional origin of two of Palenque's rulers, and individuals of African birth in a colonial cemetery in Campeche.
Karin Margarita Frei - One of the best experts on this subject based on the ideXlab platform.
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the geographic distribution of bioavailable Strontium Isotopes in greece a base for provenance studies in archaeology
Science of The Total Environment, 2021Co-Authors: Anja B Frank, Robert Frei, Ioanna Moutafi, Sofia Voutsaki, Raphael Orgeolet, Kristian Kristiansen, Karin Margarita FreiAbstract:Sr Isotopes are a powerful tool used to reconstruct human mobility in archaeology. This requires extensive bioavailable 87Sr/86Sr baselines used as reference for deciphering potential areas of origin. We define the first extensive bioavailable Sr isotope baselines for the different geographical regions and surface lithologies of Greece by combining new Sr data with previously published bioavailable 87Sr/86Sr data. We present 82 new Sr concentrations and 87Sr/86Sr signatures of plants, soil leachates, surface waters and spring waters from Central Greece and combine these with published baseline values from all over Greece. We define individual baselines for ten of the thirteen geographical regions of Greece. We also provide soil leachate 87Sr/86Sr ratios from the two archaeological Bronze Age sites of Kirrha and Ayios Vasileios in Central and Southern Greece and demonstrate the validity and applicability of the new baselines for these sites. The bioavailable 87Sr/86Sr compositions of Central Greece define a narrow range of 87Sr/86Sr values between 0.70768 - 0.71021, with the widest range observed for the soil leachates. Sr derived from carbonate weathering appears to be the most important Sr source sampled by the proxies. There is an overall larger variability in baseline ranges of the different geographical regions, the narrowest is that for West Greece and the widest that for West Macedonia. In addition, we computed statistical Sr isotope ranges for the five main surface lithological groups characterising the sampling sites of the various proxies. Narrowly ranged, unradiogenic bioavailable Sr isotope signatures are typical of areas characterised by igneous outcrops as well as by Cenozoic and Mesozoic sediments. Areas, where Palaeozoic and Precambrian bedrock outcrops dominate, produce significantly wider ranges. Our study promotes the usefulness of multi-proxy baselines for geographical reference purposes and thus their promising applicability for future human mobility studies.
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shallow retardation of the Strontium isotope signal of agricultural liming implications for isoscapes used in provenance studies
Science of The Total Environment, 2020Co-Authors: Robert Frei, Karin Margarita Frei, Soren JessenAbstract:An intensified debate centers on the use of Strontium Isotopes in surface water run-off as archive for bioavailable signatures in prehistoric provenance studies. Its use has been challenged by a recent suggestion that modern agricultural liming of farmlands exerts a serious imprint on the Strontium isotope compositions of these waters. We here present results from a soil profile beneath agricultural farmland in the glaciogenic outwash plain of central West Jutland, Denmark, which show that Strontium and its isotope composition derived from lime products is efficiently retained near the surface. Pore waters and bioavailable Strontium from the acidic zone below the surface soil depict Strontium isotope signatures that can best be explained by a mixture of silicate-derived and relic natural (not agriculturally added) carbonate-derived Strontium. We therefore argue that agricultural liming does not contaminate groundwaters and groundwater-supported surface waters, rendering reference maps based on them relevant for modern and past provenance studies.
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Strontium Isotopes and human mobility in prehistoric Denmark
Archaeological and Anthropological Sciences, 2012Co-Authors: Karin Margarita Frei, T. Douglas PriceAbstract:The principles behind the Strontium isotopic system are an important tool for archaeologists tracing human migration and patterns of movement in prehistory. However, there are several scientific challenges of analytical nature, as well as those which relate to unknown parameters inherent to the interpretation of such data. One prerequisite is the knowledge of the range of Strontium isotopic ratios that best characterize the bioavailable fractions of a particular area of interest. The study reported here attempts to establish a baseline for Strontium isotope signatures valuable for Denmark (excluding the island of Bornholm) and particularly for the use in archaeological investigations. We present Strontium isotope ratios of bones and teeth from modern mice contained in owl pellets, of snail shells, and of archaeological fauna samples. We compare these ratios with median Strontium isotope signatures characterizing human enamel populations from archaeological sites within Denmark. The fauna samples reported here range from ^87Sr/^86Sr = 0.70717 to 0.71185 with an average of 0.70919, and human enamel defines a range from ^87Sr/^86Sr = 0.7086 to 0.7110 with an average of 0.7098. In both datasets, we observe a small difference between the baseline values for the western (Jutland) and eastern (Funen, Zealand, and the southern islands) parts of Denmark. We therefore propose two slightly different baseline ranges with a partial overlap for the isotopic signatures of bioavailable Strontium fractions within Denmark, namely a range of ^87Sr/^86Sr = 0.7078–0.7098 for the western area and a range of ^87Sr/^86Sr = 0.7089–0.7108 for the eastern parts.
George D Kamenov - One of the best experts on this subject based on the ideXlab platform.
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using carbon oxygen Strontium and lead Isotopes in modern human teeth for forensic investigations a critical overview based on data from bulgaria
Journal of Forensic Sciences, 2017Co-Authors: George D Kamenov, Jason H CurtisAbstract:Isotopic data obtained from human remains can provide information about an individual’s origin, migration, and diet. We evaluate the usefulness of carbon, oxygen, Strontium, and lead Isotopes for forensic investigations by comparing data from Bulgarian teeth with data from other regions. Geo-referencing based on oxygen or Strontium Isotopes can be misleading due to overlap with other countries in Europe and other continents. Carbon and lead Isotopes, in combination with oxygen and Strontium Isotopes, provide the most useful information for identification of local vs foreigner status. In particular, high-precision Pb Isotopes show a distinct “Bulgarian” range; however, it is possible that individuals from other countries in Eastern Europe and/or central to western Asia could have overlapping isotopic values. Additional high-precision multi-isotope data from modern humans from different regions in the world are required to transition from speculative to more quantitative estimation of a geographical place of origin for unidentified human remains.
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spatial variation of Strontium Isotopes 87sr 86sr in the maya region a tool for tracking ancient human migration
Journal of Archaeological Science, 2004Co-Authors: David A Hodell, Rhonda L Quinn, Mark Brenner, George D KamenovAbstract:Strontium isotope ratios (87Sr/86Sr) in human bones and teeth have become a useful tool to study migration and sedentism of individuals from archaeological contexts. Here we analyzed 87Sr/86Sr of water, bedrock, soils, and plants across a broad geographic region to test the potential of this method in the ancient Maya area. Our aims were two-fold: first to test if the sources of dietary Strontium (i.e., plants and water) in humans reflect the 87Sr/86Sr ratio of exposed bedrock, and second, to determine whether the ranges of 87Sr/86Sr values were sufficiently distinct among the principal Maya geocultural areas to infer past migration. We identified five distinct subregions on the basis of geologic maps and evaluated the variability of 87Sr/86Sr values (values given as mean 87Sr/86Sr ±2 standard deviations; number of samples): (1) Northern Lowlands (0.70888±0.00066; n=16); (2) Southern Lowlands (0.70770±0.00052; n=86); (3) Volcanic Highlands and Pacific Coast (0.70415±0.00023; n=34); (4) Metamorphic Province (0.70743±0.00572; n=50); and (5) the Maya Mountains of Belize (0.71327±0.00167; n=3). Although the sample size is small and overlap exists in 87Sr/86Sr values among some subregions, most areas can be readily distinguished from one another on the basis of Strontium Isotopes. These subregional 87Sr/86Sr differences provide archaeologists with a powerful tool to recognize geographic “outliers” in ancient Maya burials and thereby test hypotheses concerning the origin of specific individuals, inferred population migration patterns, and the possibility of outside cultural influences in the Maya region.
Uwe Brand - One of the best experts on this subject based on the ideXlab platform.
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Strontium isotope geochemistry of modern and ancient archives tracer of secular change in ocean chemistry
Canadian Journal of Earth Sciences, 2019Co-Authors: Amir H Zaky, Uwe Brand, Dieter Buhl, Nigel J F Blamey, Aleksandra M Bitner, Alan Logan, Daniele Gaspard, A K PopovAbstract:Strontium Isotopes of marine archives provide a significant means for tracing physical and chemical processes operating over geologic time. Modern articulated brachiopods and halite samples were co...
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case studies on the utility of sequential carbonate leaching for radiogenic Strontium isotope analysis
Chemical Geology, 2018Co-Authors: Eric J Bellefroid, Uwe Brand, Noah J Planavsky, Nathaniel R Miller, Chunjiang WangAbstract:Abstract Radiogenic Strontium Isotopes (87Sr/86Sr) have been extensively used as a tool to explore a diversity of Earth system problems, including long-term global weathering rates and global sequence correlation. Strontium Isotopes are measured on a range of geological materials (e.g., calcite fossils, barites, limestone micrites), but whole-rock limestones are by far the most abundant of these materials within the geological record for paleo-seawater 87Sr/86Sr work. Whole-rock limestones, however, have a poor track record of recording primary seawater 87Sr/86Sr values. Alteration of the limestone during diagenesis and contamination from detrital aluminosilicate phases during carbonate extraction have been consistent problems. Various preparation and quality control methods have been applied to whole-rock 87Sr/86Sr work, yet there remains no consistent framework used to separate and identify both contamination and alteration simultaneously. The lack of consistent and systematic methods has made it difficult to gauge the accuracy and fidelity of much of the previously generated whole rock limestones 87Sr/86Sr data, especially for Precambrian sequences. Building on previous work, we explore a sequential leaching method designed to systematically isolate least-altered carbonate phases from detrital aluminosilicate Sr contamination and present several case studies that demonstrate the advantages of this approach. In the first case study, we use the Mid-Carboniferous Bird Spring Formation to empirically validate the accuracy of this sequential leaching method. Comparing least-altered sequentially leached whole-rock 87Sr/86Sr values with well-preserved calcite brachiopod 87Sr/86Sr values from the same section, we find near identical values. Following this first case, we studied the Neoproterozoic Dhaiqa Formation and the mid-Proterozoic Jixian Group and Muskwa Assemblage to outline a framework for identifying least-altered leachate fractions in Proterozoic carbonate samples. As a whole, we find that with this method it is possible to better identify whole-rock samples primary or least-altered carbonate fractions, and better account for alteration, providing a means to back-calculate a samples primary and least-altered marine 87Sr/86Sr value.
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Carbon, oxygen and Strontium Isotopes in Paleozoic carbonate components: an evaluation of original seawater-chemistry proxies
Chemical Geology, 2004Co-Authors: Uwe BrandAbstract:Abstract Brachiopods, trilobites, cements and whole rock (=matrix) material were evaluated for their reliability as proxies of original seawater carbon, oxygen and Strontium isotope chemistry. In this process, coeval material was evaluated from individual horizons of formations spanning the Permian to Cambrian. Unaltered shells of low-Mg calcite articulated brachiopods, retain original seawater oxygen, carbon and Strontium isotope compositions, as old as late Ordovician. Assessments of older specimens are hampered by a lack of suitable material (coeval brachiopod–whole rock sets). A definitive assessment of cement marine chemistry is difficult due to the paucity of material, but despite this caveat, cements hold some promise for retaining original carbon and possibly Strontium isotope seawater values. In contrast, the potential of whole rock material as a proxy of original seawater chemistry is quite complex. In some, but not all instances, the carbon isotopic composition of whole rock, after detailed scrutiny and evaluation, appears to represent an original seawater chemistry signal. In a few instances, their oxygen isotope compositions reflect original seawater values. Unlike the stable isotope compositions, the Strontium Isotopes of all studied whole rock material (Permian to upper Cambrian) appear not to reflect original seawater chemistry values. Thus the potential for retaining original seawater isotope chemistry and serving as specific proxies, in order of decreasing reliability, are (1) unaltered low-Mg calcite brachiopods (C, O and Sr Isotopes), (2) pristine marine cements (C and Sr Isotopes), and (3) whole rock material (C Isotopes?). Carbon, oxygen and Strontium isotope compositions of Ordovician trilobites mirror those of coeval unaltered brachiopods. Cambrian trilobites hold significant promise as an important proxy of original seawater isotope chemistry but further studies are needed to ascertain their full potential. The survey of Isotopes in some Ordovician and Cambrian intermediate/low-Mg calcite trilobites demonstrates their potential as an important proxy of original seawater chemistry.
