Готові списки джерел за темами / Stable Strontium isotopes

Добірка наукової літератури з теми "Stable Strontium isotopes"

Автор: Grafiati

Опубліковано: 6 вересня 2023

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Статті в журналах з теми "Stable Strontium isotopes"

Pollard, A. M. "Isotopes and impact: a cautionary tale." Antiquity 85, no. 328 (May 2011): 631–38. http://dx.doi.org/10.1017/s0003598x00068034.

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There can be no doubt that isotopic studies have made a huge contribution to archaeology in recent years, so much so that isotope archaeology is now seen as an essential subdiscipline of archaeology in much the same way as isotope geochemistry is a key subdiscipline of geochemistry. Ignoring for current purposes the contribution made by the measurement of a particular radioactive isotope of carbon (14C) since 1950, we can date the beginnings of isotope archaeology to the mid 1960s with the first measurements of lead isotopes in archaeological metals and slags by Brill and Wampler (1965, 1967). This was followed by carbon stable isotopes in human bone collagen in the late 1970s, building on previous work measuring σ13C in archaeological bone for radiocarbon determinations (Vogel & Van der Merwe 1977; Van der Merwe & Vogel 1978). Other isotopes followed rapidly, such as nitrogen, oxygen, sulphur and hydrogen for archaeological, palaeoecological or palaeoclimatological purposes and, more recently, the heavier radiogenic isotopes of strontium and neodymium for determining the provenance of organic and inorganic materials (Pollard & Heron 2008).

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Nguyen, Minh Quy, Long Hoang, Thi Thu Huong Le, Van Huan Luong, and Thi Tuong Hanh Vo. "Identifying the sources of produced water in the oil field by isotopic techniques." Nuclear Science and Technology 4, no. 2 (June 30, 2014): 32–41. http://dx.doi.org/10.53747/jnst.v4i2.226.

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The objective of this study is to identify the sources of the formation water in the Southwest Su Tu Den (STD SW) basement reservoir. To achieve the objective, isotopic techniques along with geochemical analysis for chloride, bromide, strontium dissolved in the water were applied. The isotopic techniques used in this study were the determination of water stable isotopes signatures (δ2H and δ18O) and of the 87Sr/86Sr ratio of strontium in rock cutting sample and that dissolved in the formation water. The obtained results showed that the stable isotopes compositions of water in the Lower Miocene was -3‰ and -23‰ for δ18O and δ2H, respectively indicating the primeval nature of seawater in the reservoir. Meanwhile, the isotopic composition of water in the basement was clustered in a range of alternated freshwater with δ18O and δ2H being –(3-4)‰ and -(54-60)‰, respectively). The strontium isotopes ratio for water in the Lower Miocene reservoir was lower compared to that for water in the basement confirming the different natures of the water in the two reservoirs. The obtained results are assured for the techniques applicability, and it is recommended that studies on identification of the flow-path of the formation water in the STD SW basement reservoir should be continued.

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Sehrawat, Jagmahender Singh, and Jaspreet Kaur. "Role of stable isotope analyses in reconstructing past life-histories and the provenancing human skeletal remains: a review." Anthropological Review 80, no. 3 (September 1, 2017): 243–58. http://dx.doi.org/10.1515/anre-2017-0017.

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AbstractThis article reviews the present scenario of use of stable isotopes (mainly δ13C, δ15N, δ18O,87Sr) to trace past life behaviours like breast feeding and weaning practices, the geographic origin, migration history, paleodiet and subsistence patterns of past populations from the chemical signatures of isotopes imprinted in human skeletal remains. This approach is based on the state that food-web isotopic signatures are seen in the human bones and teeth and such signatures can change parallely with a variety of biogeochemical processes. By measuring δ13C and δ15N isotopic values of subadult tissues of different ages, the level of breast milk ingestion at particular ages and the components of the complementary foods can be assessed. Strontium and oxygen isotopic analyses have been used for determining the geographic origins and reconstructing the way of life of past populations as these isotopes can map the isotopic outline of the area from where the person acquired water and food during initial lifetime. The isotopic values of strontium and oxygen values are considered specific to geographical areas and serve as reliable chemical signatures of migration history of past human populations (local or non-local to the site). Previous isotopic studies show that the subsistence patterns of the past human populations underwent extensive changes from nomadic to complete agricultural dependence strategies. The carbon and nitrogen isotopic values of local fauna of any archaeological site can be used to elucidate the prominence of freshwater resources in the diet of the past human populations found near the site. More extensive research covering isotopic descriptions of various prehistoric, historic and modern populations is needed to explore the role of stable isotope analysis for provenancing human skeletal remains and assessing human migration patterns/routes, geographic origins, paleodiet and subsistence practices of past populations.

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Levenets, V. V., O. Yu Lonin, O. P. Omelnik, A. O. Shchur, and G. V. Prostantinov. "Determination of the deactivating properties of shampoos for cesium, strontium and cobalt." Nuclear Physics and Atomic Energy 24, no. 2 (June 25, 2023): 162–69. http://dx.doi.org/10.15407/jnpae2023.02.162.

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The decontamination properties of shampoos for cesium, strontium, and cobalt were determined. The method has been developed for determining the decontaminating properties of shampoos. The chemical part of the study includes the preparation of hair, which consists of forced pollution and subsequent washing. Stable isotopes were used in the work. This has increased the safety of staff during chemical hair research. The analytical part includes the quantitative determination of the cesium, strontium, and cobalt in the hair, which was carried out by the Particle-Induced X-ray Emission (PIXE) method using the analytical nuclear-physical complex "Sokol". Various shampoos were analyzed, and their decontamination properties were determined. During the research, various samples of shampoos, which are presented on the market of Ukraine, were considered. It has been established that TM "Ringo" shampoo has the best deactivating properties for cesium (Kd - 574.0) and insignificant deactivating properties for strontium (Kd - 3.1) and cobalt (Kd - 3.6). It was determined that with multi-isotope contamination (a mixture of cesium, strontium, and cobalt isotopes) decrease in the deactivation coefficient for all isotopes was observed, which is due to the competition factor of the isotopes in the complexation process with shampoo. Reduction of decontaminating properties was observed on all samples of shampoos.

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Zitek, A., J. Irrgeher, M. Cervicek, M. Horsky, M. Kletzl, T. Weismann, and T. Prohaska. "Individual-specific transgenerational marking of common carp Cyprinus carpio, L., using 86Sr/84Sr double spikes." Marine and Freshwater Research 65, no. 11 (2014): 978. http://dx.doi.org/10.1071/mf13235.

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Transgenerational isotopic marking has been recognised as an efficient tool for mass marking of high numbers of fish larvae by injecting female spawners with enriched isotope solutions. So far, mainly enriched stable barium isotopes have been applied for this purpose. Here, we present an alternative approach for individual-specific transgenerational marking using strontium 86Sr/84Sr double spikes. Four isotonic double-spike solutions with different molar fractions of 86Sr and 84Sr and different total Sr concentrations were administered to four female spawners of common carp, Cyprinus carpio, L., by intraperitoneal injection, and one additional female spawner was injected a blank isotonic solution as control. Otoliths (lapilli) were sampled from juvenile offspring and analysed for their Sr isotopic composition by laser ablation–multi collector–inductively coupled plasma–mass spectrometry. Central otolith regions of the progeny of female carps treated with concentrations of at least 0.45 mg 84Sr kg–1 bodyweight and 2.28 mg 86Sr kg–1 bodyweight showed a significant shift of the absolute 88Sr/86Sr and 88Sr/84Sr isotope ratios from the natural baseline. Isotope pattern deconvolution was successfully applied for the identification of the originally injected 86Sr/84Sr molar fraction ratios of the individual double spikes. Enriched stable Sr isotope double spikes represent an important alternative to enriched stable Ba isotopes for transgenerational marking, especially in freshwater systems.

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Tchaikovsky, A., J. Irrgeher, A. Zitek, and T. Prohaska. "Isotope pattern deconvolution of different sources of stable strontium isotopes in natural systems." Journal of Analytical Atomic Spectrometry 32, no. 11 (2017): 2300–2307. http://dx.doi.org/10.1039/c7ja00251c.

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Halicz, Ludwik, Irina Segal, Noa Fruchter, Mordechai Stein, and Boaz Lazar. "Strontium stable isotopes fractionate in the soil environments?" Earth and Planetary Science Letters 272, no. 1-2 (July 2008): 406–11. http://dx.doi.org/10.1016/j.epsl.2008.05.005.

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Fiket, Željka, Martina Furdek Turk, Maja Ivanić, and Goran Kniewald. "Non-traditional stable isotope signatures in geological matrices as a tool for interpreting environmental changes – a review." Geologia Croatica 74, no. 2 (June 30, 2021): 177–87. http://dx.doi.org/10.4154/gc.2021.12.

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The development of new analytical techniques enabled the precise determination of the expanded set of stable isotopes and provided new insight into existing geological issues. This review outlines recent studies of non-traditional isotope signatures in geological matrices, summarizing in one place, new data for the stable isotopes of Ca, Mg, Sr, Li, Ni, Cr, and Cu and their application in the interpretation of environmental processes. Although some, such as δ44Ca and δ26Mg, have previously been used to track changes in seawater chemistry throughout geological history, recent studies report their application as geochemical proxies of post-depositional processes. Similarly, isotopic signatures of strontium, previously used in radioactive isotope chronology, and δ7Li, used in tracing plate subduction and crust/mantle material cycling, found a new application in studies of weathering patterns. The use of δ53Cr and δ 65Cu isotope signatures, on the other hand, reflects their fractionation under different redox conditions, whereas δ60Ni, due to its adsorption and co-precipitation with sulfide species and Fe-Mn phases, is used in interpreting the contributions of different material sources. And while the isotopic signatures of all these elements indicate certain environmental conditions and processes (e.g. post-depositional processes, redox conditions, organic matter input, the contribution of sources, etc.), by combining them a more comprehensive insight into the investigated environment can be achieved.

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Carleton, Scott. "Identifying Tributaries to Jackson Lake Important for Snake River Cutthroat Trout Recruitment." UW National Parks Service Research Station Annual Reports 34 (January 1, 2011): 27–32. http://dx.doi.org/10.13001/uwnpsrc.2011.3851.

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Across their range, native salmonid species are imperiled due to habitat loss, alteration, and competition with non-native salmonids. New challenges, such as the effects of climate change on stream flow and water temperature create new problems for these species and highlight the importance of understanding their juvenile and adult life histories. Specifically, identifying life history movement patterns as it relates to spawning sites and juvenile rearing streams. We measured strontium isotope values of 13 tributaries and mainstem waters of the lower Snake River and Jackson Lake as well as otoliths collected from resident/juvenile cutthroat trout to determine if we could find unique isotopic signatures throughout the watershed. Strontium isotope values were similar for otoliths and water samples collected at the same location. Strontium isotope yielded unique isotope values across the watershed and between tributaries and the Snake River and Jackson Lake. Only three tributaries were undifferentiated using strontium stable isotopes. These were Pilgrim, Dime, and Sheffield Creeks. Due to their close proximity geographically and their geologic similarities it is not surprising we were unable to differentiate these three tributaries from each other. Future work using trace element analysis might provide further differentiation between these three creeks. Using this new information, we can now begin to look at adult cutthroat from Jackson Lake and the Snake River and determine their natal origins and fidelity to spawning tributaries. Using this information, managers can guide conservation efforts for cutthroat trout in the Jackson Lake watershed.

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West, Jason B., Janet M. Hurley, Francis Ö. Dudás, and James R. Ehleringer. "The Stable Isotope Ratios of Marijuana. II. Strontium Isotopes Relate to Geographic Origin." Journal of Forensic Sciences 54, no. 6 (November 2009): 1261–69. http://dx.doi.org/10.1111/j.1556-4029.2009.01171.x.

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Дисертації з теми "Stable Strontium isotopes"

Stevenson, Emily Isabel. "Stable strontium isotope fractionation in marine and terrestrial environments." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:a2d97fc7-3e9d-484a-8026-11c118fcc3fd.

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The work reported in this thesis applies a new isotope tracer, stable strontium isotopes (δ^88/86Sr), to address questions concerning changes in global climate that occur in response to continental weathering processes, and to constrain the modern marine geochemical Sr cycle. Stable Sr isotopes are a relatively new geochemical proxy, and as such their behavior needs to be understood in differing forms of marine calcium carbonate, the archives from which records of past stable Sr variability in the oceans can be constructed. Foraminifera, coccoliths and corals (both aragonite and high Mg calcite) acquire δ^88/86Sr values lighter than that of modern day seawater, (approximately 0.11, 0.05, 0.2 and 0.19 ‰ lighter than seawater at ~25°C respectively) providing a measureable offset which can be used to constrain the modern Sr outputs from the ocean and provide a better understanding of the modern Sr cycle. Using foraminifera as a sedimentary archive the first marine δ^88/86Sr record of seawater over the last two glacial cycles has been constructed, and used to investigate changing carbonate input and output over this 145 kyr period. Modelling of the large excursion of δ^88/86Sr to heavier values during Marine Isotope Stage (MIS) 3, reveals that this is more likely to be due to local changes in seawater or post-depositional alteration, rather then whole ocean changes. In the terrestrial environment δδ88/86^Sr has been measured in the dissolved load of rivers from the Himalaya. It is found that, in general, rivers draining carbonate catchments possess lighter isotopic δ^88/86Sr values than those from rivers draining silicates. Covariations of either δ88/86Sr vs. δ30Si or δ^88/86Sr vs. 1/[Sr] can be used to distinguish between rivers draining different catchment areas.

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Vaiglova, Petra. "Neolithic agricultural management in the Eastern Mediterranean : new insight from a multi-isotope approach." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:c8824136-da35-43b2-a700-f458d0cc2fdf.

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The work presented in this dissertation explores the nature of agro-pastoral strategies developed by Neolithic farmers as a way to understand how early food production was inter-twined with environmental and socio-economic opportunities and constraints. Towards this end, a multi-isotope approach is used to address questions of scale and intensity of crop cultivation and animal management at the archaeological sites of Kouphovouno, southern Greece, Makriyalos, northern Greece, and Çatalhöyük, south-central Turkey. Measurements of stable carbon, nitrogen, oxygen and strontium isotope values of carbonized plant remains, human and animal bone collagen and animal tooth enamel are used to examine the similarities and differences in the types of treatments that individual species of plants and animals received during the agricultural cycle at the distinct locations. The results show that farmers at the three sites developed variable methods for exploiting the arable and pastoral landscape and catering to their economic and culinary needs. The discussion considers the implications of these findings to our understanding of the complexity and adaptability of early farming systems.

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Sutcliffe, Nadine C. "Strontium stable isotope behaviour accompanying melting and magmatism in the Earth-Moon system." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:826ae843-3115-4a3e-975a-f6306f923d4e.

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This thesis concerns the application of a new technique for measuring the stable isotopes of Sr, specifically pertaining to mass dependent fractionation in high temperature processes on the Earth and Moon. Processes such as mantle melting and differentiation on Earth and the formation of the Lunar Magma Ocean are investigated by the application of a double-spike TIMS method to terrestrial and lunar material to obtain high-precision ⁸⁷Sr/⁸⁶Sr, ⁸⁸Sr/⁸⁶Sr and ⁸⁴Sr/⁸⁶Sr data. Measurements of mantle-derived mafic material provide insights into the ⁸⁸Sr/⁸⁶Sr composition of the silicate mantle. Ocean Island Basalts possess restricted δ⁸⁸Sr compositions, whilst Mid-Ocean Ridge Basalts from the Pacific, Atlantic and Indian ridges reveal variations in δ⁸⁸Sr, the majority of which is seen within the FAMOUS section of the Mid-Atlantic Ridge. These variations are attributed partly due to the effects of plagioclase crystallisation and partly due to mantle source heterogeneity. Analyses of mineral separates from three different igneous systems provide an understanding of δ⁸⁸Sr fractionation at a mineral-scale. The possibility of δ⁸⁸Sr fractionation as a result of magmatic differentiation has also been assessed, and found to occur between the basalt and rhyolitic end-members of the Icelandic Hekla suite. Variations in the ⁸⁷Sr/⁸⁶Sr ratios of these rocks are also found, and considered most likely to be due to contamination. Analyses of lunar rocks indicate that the highland suite appears to be relatively uniform in δ⁸⁸Sr, whilst significant fractionation to light δ⁸⁸Sr compositions occurs in the mare basalts. Such variations are thought to be associated with the crystallisation of plagioclase during the differentiation of the lunar magma ocean. Lastly, precise ⁸⁷Rb/⁸⁶Sr and ⁸⁷Sr/⁸⁶Sr data yield a model age for the Moon of 4.523 ± 0.019 Ga.

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Gentry, David Keith. "Seasonal isotope and trace-metal profiles of serially-sampled Conus gastropods: proxies for paleoenvironmental change." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/3871.

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We test the fidelity of shallow-water gastropod skeletons as multi-proxy archives of seasonal paleo-environmental change by performing isotopic and trace-metal analyses on specimens of Conus ermineus from the Gulf of Mexico. Four adult specimens were collected from Stetson Bank in the Flower Garden Banks National Marine Sanctuary during the summer of 2002. Shell samples were milled along axes of growth to produce time-series profiles spanning up to eight years. We corrected the profiles for growth rate effects and compared the tuned results with in situ temperature and salinity records at the reef surface and temperature profiles from nearby surface buoys. Examination of sample densities in δ18O cycles shows that shell growth is faster during summers and slower during winters. Tuning the profiles versus time yields δ18O values that co-vary closely with seasonal temperatures to a high degree of coherency (R2 = 0.84). The δ13C profiles show cyclic variation modified by ontogenetic decreases in δ13C. These ontogenetic trends are attributable to decreasing metabolic efficiency, while seasonal cycles reflect hydrographic changes in the gastropodsÂ habitat. Salinity and δ13C of dissolved inorganic carbon show a strong correlation at Stetson Bank (R2 = 0.80), and early summer shell δ13C minima coincide with local salinity minima during times of peak river discharge. The terminations of these δ13C minima occur during annual upcoast reversals of shelf currents in this area. These effects are augmented by summer stratification and productivity minima that further decrease seawater δ13C. Sr/Ca ratios increase through ontogeny, most likely due to decreasing metabolic efficiency. However, seasonal variations in Sr/Ca profiles show strong similarity with δ18O profiles, confirming the temperature dependence of Sr/Ca and minimal influence of salinity on shell δ18O at Stetson Bank. The results of this study show that tuned δ18O and Sr/Ca profiles can be used to reconstruct seasonal paleotemperatures. Carbon isotope profiles and environmental data also demonstrate the utility of Conus δ13C as a proxy for freshwater flux and shelf circulation.

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Salgado, Souto Sergio Adrian, and Souto Sergio Adrian Salgado. "A Re-Os Geochronology and Multi Stable Isotope (C, N, S, Sr, Pb) Systematics of Source Rocks and Crude Oils from the Sonda de Campeche Petroleum System, Mexico." Diss., The University of Arizona, 2018. http://hdl.handle.net/10150/626760.

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In this work, I present a multi-isotopic study (carbon, nitrogen, sulfur, strontium and lead) and Re-Os geochronology in rocks and crude oils of the Sonda de Campeche Petroleum System (SCPS). Since crude oils are complicated chemical systems easily disturbed, the Re-Os isotopic system could be affected if secondary processes perturb crude oils. Therefore, the multi stable isotopic study allows the identification of the presence and grade of these secondary processes in crude oils. The δ13C values of crude oils from the SCPS distinguish between: 1) crude oils with the fingerprint of source rocks of hydrocarbons (-28.3 to -26.7 ‰), and 2) crude oils with the fingerprint of the reservoir rocks (-25.5 to -24.9 ‰). Similarly, the δ15N values reveal that crude oils, during migration or trapping processes mimic the isotopic composition of the reservoir rocks of the Ek-Balam Formation. Furthermore, the δ34S values of crude oils from the SCPS (-8.0 to -2.5 ‰) show an absence of a thermal sulfate reduction (TSR) signature, which likely means that the use of Re-Os systematics in crude oils and rocks in the SCPS is appropriate. Strontium and lead measurements show crude oils have an isotopic composition different from rocks from the Edzna Formation but similar to rocks of the Akimpech and Ek-Balam formations, indicating that crude oils received Sr and Pb from the trapping rocks during migration or trapping processes, producing a isotopic mixing trend with rocks of these formations. Specifically, the lead isotope composition allows the identification of a source of lead never recorded before, the Guichicovi Complex. The isotopic data suggest that this Grenville Complex has been feeding with detrital material to the sedimentary rocks from Bacab, Ek-Balam and Akimpech formations in the SCPS, and in consequence contributing to the final isotopic composition of crude oils as well. Re-Os geochronology of rocks from the Edzna and Akimpech formations (152 ± 4 Ma; and 158.6 ± 5.5 Ma, respectively) provides precise ages of deposition that coincide with the ages proposed in previous studies based on the fossil record. Re-Os geochronology in crude oils yield ages with low uncertainty and moderate MSWD values, reflecting a rapid formation and migration process that occurred during evolution of the SCPS. The age of crude oils (28.3 ± 5.5 Ma) broadly agrees with petroleum generation models proposed by PEMEX.

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McCall, Ashley E. "The Relationship of Stable Isotopes to Late Woodland and Fort Ancient Agriculture, Mobility, and Paleopathologies at the Turpin Site." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1367924972.

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Wilson, Jessica Norman. "Stable Isotopes and Trace Elements in Tooth Enamel Bioapatite: Effects of Diagenesis and Pretreatment on Primary Paleoecological Information." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4965.

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The geochemical analysis of bioapatite in vertebrate skeletal tissues is an important tool used to obtain ecological information from fossil animals. An important consideration when conducting stable isotope and trace element analyses is obtaining biogenic information that has been unaffected by diagenetic processes. A two-step pretreatment procedure is commonly used remove diagenetically altered material by removing organic material, via an oxidation reaction with H2O2 or NaOCl, and secondary carbonate, via dissolution in dilute acetic acid, from bioapatite. While much work has been done to determine the efficacy of the pretreatment process, little research has been conducted to determine the potential effects of this process on the oxygen isotope composition of enamel bioapatite. A comparison between δ18O values of fossil enamel treated with 18O-depleted (δ18O = -10.0 / V-SMOW) and 18O-enriched solutions (δ18O = +16.4 / V-SMOW). On average, samples treated with 18O-enriched solutions had δ18O values at least 0.4 / V-PDB more positive than samples treated with 18O-depleted solutions. These results suggest that the isotopic composition of solutions used in the pretreatment process can significantly affect the δ18O values of fossil enamel prior to isotopic analysis. Diagenetic alteration can potentially be assessed using the linear relationship between δ18O values of the carbonate and phosphate components of bioapatite, as any deviation from a slope of 1 suggests alteration. Comparing the relationship between δ18Op and δ18Oc for fossil mammals from the Hadar Formation suggests that this method is successful at identifying samples that are significantly different from the remaining samples due to diagenetic alteration. The relationship between δ18Oc and δ18Op for the majority of sampled fossils from the Hadar Formation has a slope very close to 1 with an average offset, and apparent fractionation factor, between δ18Oc and δ18Op consistent with modern mammals. Therefore, it is likely that many of the fossil mammals sampled from the Hadar Formation retain in vivo δ18O values relating to the δ18O value of the water they consumed. The reliability of paleodietary reconstructions using trace element ratios (notably Sr/Ca and Ba/Ca) is strongly dependent on the preservation of biogenic trace element concentrations. Although most trace element ratio research relies on bone bioapatite, enamel has a better preservation potential and may successfully preserve biogenic trace element relationships. An analysis of Sr/Ca, Ba/Ca, and Zn/Ca ratios indicates that, despite rare earth element concentrations greater than the 1ppm observed in modern enamel, mammals from the Hadar and Busidima formations potentially reflect feeding strategies observed in modern counterparts, i.e. grazers have higher Sr/Ca and Ba/Ca ratios than browsers and omnivores

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Widanagamage, Inoka Hasanthi. "STABLE STRONTIUM ISOTOPE FRACTIONATION IN ABIOTIC AND MICROBIALLY MEDIATED BARITE IN MODERN CONTINENTAL SETTINGS." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1445344122.

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Pritchard, Jodie Lee, and jodie_pritchard@hotmail com. "Dynamics of stream and groundwater exchange using environmental tracers." Flinders University. School of Chemistry, Physical & Earth Science, 2006. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20060407.122526.

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Regions of surface water and groundwater exchange are major sites for the transfer and transformation of solutes and nutrients between stream and subsurface environments. Conventional stream and groundwater exchange investigations are limited by methodologies that require intensive field investigations and/or the set-up of expensive infrastructure. These difficulties are exacerbated where hydraulic gradients are very low and stream discharge highly variable. This thesis uses a suite of environmental tracers (Cl-, Rn-222, H-2 & O-18, Sr-87/Sr-86) to characterise the extent of stream and groundwater exchange between a sand bed stream and adjacent alluvial aquifer in a subtropical catchment (the Wollombi Brook) of eastern Australia. The aims were to identify sources and relative contributions of different sources of groundwater to stream discharge and specifically to improve the methodology of using Rn-222 to obtain quantitative estimate of groundwater fluxes. The sensitivity of the Rn-222 technique for identifying groundwater discharge based on the Rn-222 concentration in stream water was improved via an iterative numerical approach to account for Rn-222 loss from stream water via turbulent gas exchange and radioactive decay. Optimal distances between stream sampling points for defining the magnitude of groundwater discharge to stream flow based on Rn-222 concentrations in stream water is a function of average stream velocity and water depth. The maximum allowable distance between sampling points for determining the magnitude of groundwater discharge to the Wollombi Brook was 2 km. This work showed that groundwater discharged to all reaches of the Wollombi Brook during baseflow and flood recession conditions. Alluvial groundwater contributed less than 30% of water to stream flow in the mid Wollombi Brook catchment. Dilution of steady-state Rn-222 concentrations measured in transects from the stream to the alluvial sediments showed that significant surface water and groundwater exchange occurs even when gradients between surface water and groundwater are low. Lateral stream water influx to the adjacent alluvial aquifer was more extensive in the lowland areas of the Wollombi Catchment during low flow than flood recession conditions. Extensive stream water influx to the adjacent alluvial aquifer occurs contrary to the net direction of surface water and groundwater flux (as indicated by hydraulic gradients toward the stream channel). The rate of stream and groundwater exchange within the adjacent alluvial aquifer appears to be greatest during baseflow conditions. Fresh alluvial groundwater appeared to provide a buffer against higher salinity regional groundwater discharge to the alluvial aquifer in some reaches of the Wollombi Brook catchment. Pumping of the alluvial aquifer and diversions of surface water may jeopardise the water quality and volume of the alluvial aquifer and induce water flow from the regional aquifer toward the stream, potentially salinising the fresh alluvial aquifer and subsequently the stream. The change in the Cl- concentration and the variation in slope of the deuterium ï¿½ oxygen-18 line between consecutive stream sampling points could be used to differentiate between regional and alluvial groundwater discharge to stream flow. Incorporating this information with three-component end-member mixing using [Sr2+] and Sr-87/Sr-86 showed that stream and alluvial groundwater exchange within the stream channel was highest in the lowland floodplains during low flow conditions. The least stream and alluvial groundwater exchange occurred in the low streambed gradient mid reaches of the Wollombi Brook regardless of stream stage. The greatest difference in the degree of stream and alluvial groundwater exchange between high and low stream stages occurred in the lowland floodplains of the Wollombi Brook.

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Quinn, Carolyn J., and n/a. "Stable isotopes and diet : indications of the marine and terrestrial component in the diets of prehistoric populations from New Zealand and the Pacific." University of Otago. Department of Anthropology, 1990. http://adt.otago.ac.nz./public/adt-NZDU20070601.115004.

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The importance of marine versus terrestrial foods in prehistoric Pacific and New Zealand diets, and the adaptation of the Polynesian diet to new enviroments, is examined through the analysis of the ratios in human bone of the stable isotopes of carbon, nitrogen and sulphur. In particular, this study seeks to obtain quantitative information which could provide answers to five main questions, relating to the subsistence focus of the early Lapita colonists in the Pacific, the significance of suger cane in the diets of early Pacific populations, the proportions of reef versus open ocean and terrestrial versus marine foods in these diets, and the identification of populations with pronounced marine or pronounced terrestrial diets. One hundred and nineteen samples of human bone from 13 sites throughtout the Pacific and New Zealand were processed. Nitrogen values were obtained directly from bone powder, while carbon values were determined from collagen produced by digesting bone powder in phosphoric acid. Sulphur evaluations were determined from a BaSo⁴ precipitate, produced after combustion of the collagen samples in a Parr bomb. Interpretation of results is approached from a comparative point of view, which enables the proportions of marine and terrestrial foods in the diets of each study group to be assessed in relation to the diets of all the other groups. Additional information on the composition of the diets is gained by comparing the stable isotope values obtained in this study with published values of other human populations, and of marine and terrrestrial plants and animals. The potential of stable isotope analysis to identify the composition of prehistoric New Zealand and Pacific diets is confirmed. A unique marine adaptation is revealed from the analysis of the Chatham Islands Moriori who appear to have focused almost exclusively on marine resources. In contrast, a highly terrestrial diet is suggested for groups from Nebira in Papua New Guinea and Lake Rotoiti in New Zealand.

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Книги з теми "Stable Strontium isotopes"

Hemer, Katie A., and Jane A. Evans. The Contribution of Stable Isotope Analysis to the Study of Childhood Movement and Migration. Edited by Sally Crawford, Dawn M. Hadley, and Gillian Shepherd. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199670697.013.27.

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Stable isotope analysis is firmly established as a method for the investigation of past population mobility. The distinction between local and non-local individuals within a cemetery population relies on identifying an individual’s place of childhood residence through the analysis of strontium and oxygen isotopes present in human tooth enamel. Traditionally, studies investigating mobility focus on the analysis of a single tooth. More recently, however, it has become apparent that in order to investigate the mobility of an individual during childhood—and thus to consider the importance of children in the migration process—it is necessary to analyse a series of teeth which form at different stages during the early years of life. This chapter will consider the potential of—and challenges surrounding—this scientific approach to the investigation of childhood mobility in the past.

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Частини книг з теми "Stable Strontium isotopes"

Ericson, J. E. "Some Problems and Potentials of Strontium Isotope Analysis for Human and Animal Ecology." In Stable Isotopes in Ecological Research, 252–59. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4612-3498-2_14.

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Graustein, W. C. "87Sr/86Sr Ratios Measure the Sources and Flow of Strontium in Terrestrial Ecosystems." In Stable Isotopes in Ecological Research, 491–512. New York, NY: Springer New York, 1989. http://dx.doi.org/10.1007/978-1-4612-3498-2_28.

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Dewan, Nitika, Brian J. Majestic, Michael E. Ketterer, Justin P. Miller-Schulze, Martin M. Shafer, James J. Schauer, Paul A. Solomon, et al. "Tracing Dust Sources Using Stable Lead and Strontium Isotopes in Central Asia." In ACS Symposium Series, 79–98. Washington, DC: American Chemical Society, 2015. http://dx.doi.org/10.1021/bk-2015-1210.ch004.

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Attendorn, H. G., and R. N. C. Bowen. "Rubidium-strontium dating." In Radioactive and Stable Isotope Geology, 159–91. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5840-4_7.

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Walker, James C. G. "How to Calculate Isotope Ratios." In Numerical Adventures with Geochemical Cycles. Oxford University Press, 1991. http://dx.doi.org/10.1093/oso/9780195045208.003.0008.

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The calculation of isotope ratios requires special consideration because isotope ratios, unlike matter or energy, are not conserved. In this chapter I shall show how extra terms arise in the equations for the rates of change of isotope ratios. The equations developed here are quite general and can be applied to most of the isotope systems used in geochemistry. As an example of the application of these new equations, I shall demonstrate a simulation of the carbon isotopic composition of ocean and atmosphere and then use this simulation to examine the influence on carbon isotopes of the combustion of fossil fuels. As an alternative application I shall simulate the carbon isotopic composition of the water in an evaporating lagoon and show how the composition and other properties of this water might be affected by seasonal changes in evaporation rate, water temperature, and biological productivity. Equations for the rates of change of individual isotopes in a reservoir are not essentially different from the equations for the rates of change of chemical species. Isotopic abundances, however, are generally expressed as ratios of one isotope to another and, moreover, not just as the ratio but also as the departure of the ratio from a standard. This circumstance introduces some algebra into the derivation of an isotopic conservation equation. It is convenient to pursue this algebra just once, as I shall in this section, after which all isotope simulations can be formulated in the same way. I shall use the carbon isotopes to illustrate this derivation, but the same approach can be used for the isotopes of other elements, such as sulfur, oxygen, nitrogen, hydrogen, or strontium. The most abundant isotope of carbon has a mass of 12 atomic mass units, 12C. A less abundant stable isotope is 13C. And much less abundant is the radioactive isotope 14C, also called radiocarbon. It is convenient to express the abundances of these rare isotopes in terms of ratios of the number of atoms of the rare isotope in a sample to the number of atoms of the abundant isotope. We call this ratio r, generally a very small number.

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"The Chemistry of Human Bone: Diet, Nutrition, Status and Mobility." In Archaeological Chemistry, 428–73. 3rd ed. The Royal Society of Chemistry, 2016. http://dx.doi.org/10.1039/bk9781782624264-00428.

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The measurement of the stable isotope ratios of carbon and nitrogen in human bone collagen revolutionized archaeology in the late 1970s, when it was shown to be a precise indicator for the spread of maize agriculture in North America. Diagenetic alteration of the collagen was shown to be essentially irrelevant in such work, unlike the problems of post-mortem alteration which confused the studies of dietary reconstruction from trace elements in bone, which were being carried out at the same time. Stable isotopes in collagen have gone on to become ubiquitous in archaeology, addressing such major issues as the dietary change from marine to terrestrial protein sources during the Mesolithic–Neolithic transition in Europe. Comparison of stable isotopes in different elements of the same human skeleton have also been used to detect lifetime mobility, using the fact that some skeletal elements are remodelled faster than others. Other aspects, such as gender and status differences in dietary habits, and the effect of weaning on infant skeletons, have also been studied. The greater durability and resistance to diagenesis of dental enamel has also been used to study mobility, and to identify ‘foreigners’ in burial assemblages, using the isotopic measurements of strontium and oxygen. The stability of enamel has also allowed dietary behaviour to be studied on fossil hominins, using measurements of carbon and oxygen isotopes in the carbonate phase within the enamel. It is now relatively routine to carry out ‘isotopic ecology’ studies in many parts of the world, where human and animal bones are used to reconstruct complete food webs. The chemical and isotopic study of bone has been one of the great success stories of archaeological chemistry over the last 50 years.

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Jobling, Mark, and Andrew Millard. "Isotopic and Genetic Evidence for Migration in Medieval England." In Migrants in Medieval England, c. 500-c. 1500, 19–61. British Academy, 2020. http://dx.doi.org/10.5871/bacad/9780197266724.003.0002.

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Two sources of evidence, ratios of stable isotopes and sequences of DNA molecules, can illuminate histories of human migration. Studies of skeletal remains from medieval cemeteries in England, using oxygen and strontium isotope analyses to investigate places of childhood residence, reveal more mobility than anticipated and sometimes migration from unexpected directions. Whole-genome sequencing of a few individuals provides new insights into Anglo-Saxon migration and the diversity of origins of individuals buried in Roman York. Analysis of DNA variation in modern samples provides only indirect evidence about the medieval period, and considerable uncertainty about the timing of any deduced past migration events. This chapter argues that an explicit modelling framework should be developed permitting combined interpretation of DNA data (modern and ancient) and isotope data which, when applied to the same samples, will provide new insights about migration and mobility, and about the reliability and interpretation of these two sources of evidence.

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"Missing in action during the Thirty Years’ War: Provenance of soldiers from the Wittstock battlefield, October 4, 1636. An investigation of stable strontium and oxygen isotopes." In Population Dynamics in Prehistory and Early History, 323–36. De Gruyter, 2012. http://dx.doi.org/10.1515/9783110266306.323.

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Barrera, E., J. Baldauf, and K. C. Lohmann. "Strontium Isotope and Benthic Foraminifer Stable Isotope Results from Oligocene Sediments at Site 803." In Proceedings of the Ocean Drilling Program, 130 Scientific Results. Ocean Drilling Program, 1993. http://dx.doi.org/10.2973/odp.proc.sr.130.022.1993.

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Alt, J. C., D. A. H. Teagle, W. Bach, A. N. Halliday, and J. Erzinger. "Stable and Strontium Isotopic Profiles through Hydrothermally Altered Upper Oceanic Crust, Hole 504B." In Proceedings of the Ocean Drilling Program, 148 Scientific Results. Ocean Drilling Program, 1996. http://dx.doi.org/10.2973/odp.proc.sr.148.117.1996.

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Тези доповідей конференцій з теми "Stable Strontium isotopes"

Wood, Madison, Michael Tatzel, Susan Pit, and Adina Paytan. "Stable and Radiogenic Strontium Isotopes in Seawater over the Late Quaternary." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2886.

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Padiyath, Nemeer, Prasoon Raj, and Diana Francis. "Soil-to-plant transfer factors in arid regions using stable isotopes of caesium and strontium in local vegetables." In RAD Conference. RAD Centre, 2021. http://dx.doi.org/10.21175/rad.abstr.book.2021.34.10.

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Denton, Mark S., and Mercouri G. Kanatzidis. "Innovative Highly Selective Removal of Cesium and Strontium Utilizing a Newly Developed Class of Inorganic Ion Specific Media." In ASME 2009 12th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2009. http://dx.doi.org/10.1115/icem2009-16221.

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Highly selective removal of Cesium and Strontium is critical for waste treatment and environmental remediation. Cesium-137 is a beta-gamma emitter and Strontium-90 is a beta emitter with respective half-lives of 30 and 29 years. Both elements are present at many nuclear sites. Cesium and Strontium can be found in wastewaters at Washington State’s Hanford Site, as well as in wastestreams of many Magnox reactor sites. Cesium and Strontium are found in the Reactor Coolant System of light water reactors at nuclear power plants. Both elements are also found in spent nuclear fuel and in high-level waste (HLW) at DOE sites. Cesium and Strontium are further major contributors to the activity and the heat load. Therefore, technologies to extract Cesium and Strontium are critical for environmental remediation waste treatment and dose minimization. Radionuclides such as Cesium-137 and Strontium-90 are key drivers of liquid waste classification at light water reactors and within the DOE tank farm complexes. The treatment, storage, and disposal of these wastes represents a major cost for nuclear power plant operators, and comprises one of the most challenging technology-driven projects for the DOE Environmental Management (EM) program. Extraction technologies to remove Cesium and Strontium have been an active field of research. Four notable extraction technologies have been developed so far for HLW: solvent extraction, prussian blue, crystalline silicotitanate (CST) and organic ion-exchangers (e.g., resorcinol formaldehyde and SuperLig). The use of one technology over another depends on the specific application. For example, the waste treatment plant (WTP) at Hanford is planning on using a highly-selective organic ion-exchange resin to remove Cesium and Strontium. Such organic ion-exchangers use molecular recognition to selectively bind to Cesium and Strontium. However, these organic ion-exchangers are synthesized using multi-step organic synthesis. The associated cost to synthesize organic ion-exchangers is prohibitive and seriously limits the scope of applications for organic ion-exchangers. Further issues include resin swelling, potential hydrogen generation and precluding final disposal by vitrification without further issues. An alternative to these issues of organic ion-exchangers is emerging. Inorganic ion-exchangers offer a superior chemical, thermal and radiation stability which is simply not achievable with organic compounds. They can be used to remove both Cesium as well as Strontium with a high level of selectivity under a broad pH range. Inorganic ion-exchangers can operate at acidic pH where protons inhibit ion exchange in alternative technologies such as CST. They can also be used at high pH which is typically found in conditions present in many nuclear waste types. For example, inorganic ion-exchangers have shown significant Strontium uptake from pH 1.9 to 14. In contrast to organic ion-exchangers, inorganic ion-exchangers are not synthesized via complex multi-step organic synthesis. Therefore, inorganic ion-exchangers are substantially more cost-effective when compared to organic ion-exchangers as well as CST. Selective removal of specified isotopes through ion exchange is a common and proven treatment method for liquid waste, yet various aspects of existing technologies leave room for improvement with respect to both cost and effectiveness. We demonstrate a novel class of inorganic ion-exchangers for the selective removal of cesium and strontium (with future work planned for uranium removal), the first of a growing family of patent-pending, potentially elutable, and paramagnetic ion-exchange materials [1]. These highly selective inorganic ion-exchangers display strong chemical, thermal and radiation stability, and can be readily synthesized from low-cost materials, making them a promising alternative to organic ion-exchange resins and crystalline silicotitanate (CST). By nature, these inorganic media lend themselves more readily to volume reduction (VR) by vitrification without the issues faced with organic resins. In fact, with a simple melting of the KMS-1 media at 650–670 deg. C (i.e., well below the volatilization temperature of Cs, Sr, Mn, Fe, Sb, etc.), a VR of 4:1 was achieved. With true pyrolysis at higher temperatures or by vitrification, this VR would be much higher. The introduction of this new family of highly specific ion-exchange agents has potential to both reduce the cost of waste processing, and enable improved waste-classification management in both nuclear power plants (for the separation of Class A from B/C wastes) and DOE tank farms [for the separation of low level waste (LLW) from high level waste (HLW)]. In conclusion, we demonstrate for the first time a novel inorganic ion-exchanger for the selective removal of Cesium and Strontium. These inorganic ion-exchangers are chemical, thermal and radiation stable. These inorganic ion-exchangers can be synthesized in a cost-effective way which makes them significantly more effective than organic ion-exchange resin and CST. Finally, new thermal options are afforded for their final volume reduction, storage and disposal.

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Wood, Madison, Ana Kolevica, Anton Eisenhauer, Mathis Hain, Andy Ridgewell, Elizabeth Griffith, and Adina Paytan. "Seawater stable strontium isotope fluctuations over glacial/interglacial cycles." In Goldschmidt2021. France: European Association of Geochemistry, 2021. http://dx.doi.org/10.7185/gold2021.4516.

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Robinson, Lewis, Kevin Burton, Geoff Nowell, Helen Williams, Vicente Lopez Sanchez-Vizcaino, and Carlos J. Garrido. "Strontium stable isotope behaviour accompanying dehydration of antigorite-bearing serpentinite." In Goldschmidt2021. France: European Association of Geochemistry, 2021. http://dx.doi.org/10.7185/gold2021.7945.

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Chernykh, A. V., A. N. Pyrayev, and F. F. Dultsev. "NEW DATA ON THE ISOTOPIC COMPOSITION OF BRINES OF OIL AND GAS DEPOSITS OF THE SIBERIAN PLATFORM." In All-Russian Youth Scientific Conference with the Participation of Foreign Scientists Trofimuk Readings - 2021. Novosibirsk State University, 2021. http://dx.doi.org/10.25205/978-5-4437-1251-2-121-125.

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The new isotope-geochemical data on the Siberian platform supersaturated brines of a wide stratigraphic range (from Riphean to Ordovician) are presented. There is a wide range of oxygen and hydrogen stable isotope composition in the studied brines: from –133 to –17,5 % for δD and from –17,0 to –2,5 % for δ18O. The δD and δ18O values point on the sedimentation-metamorphic genesis of the brines. The carbon isotope composition of the DIC in brines range from –31 to +12,7 %. It is supposed that DIC has the biogenic (bacterial) origin. The youngest brine DIC has the heaviest carbon isotope composition whereas the oldest brine DIC has the biggest concentration of 12C. The strontium ratios of the studied brines divide them into two groups: with 87Sr/86Sr ratios, close to those of the modern ocean waters, and brines with 87Sr/86Sr values significantly exceeding modern ocean strontium ratios. It is assumed that the burial of the brines of the second group took place in the presence of clastic material of the continental crust, with a high content of radioactive 87Rb.

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Xu, Juan, and Shouye Yang. "Critical Considerations for Precise Determination of Stable Strontium Isotopic Compositions by MC-ICPMS." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2944.

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Khalifa, Aqeel, Paul Tarabbia, Mohammad A. Alrowaie, and Mohamed Soua. "Significance and Implications of Diagenetic Nodular Anhydrite on Sandstone Reservoirs Quality." In SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210403-ms.

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Abstract Diagenetic nodular anhydrite observed in fluvio-aeolian-lacustrine and glacial sandstones has significant implications to reservoir quality. This type of nodular cement is spatially and volumetrically variable within these reservoirs. Its presence impacts subsurface formation evaluation and porosity calculations. Thus, the investigation of these nodules was carried out using: core image analysis; thin sections petrography; micro computed tomography (MicroCT) scans; bulk rock X-Ray Diffraction (XRD); sulfur & strontium isotope analyses. Where core was unavailable, geochemical data and resistivity-based image logs were used to expand the anhydrite characterization to derive field wide distributions. Bulk rock XRD and thin section-based petrographic studies indicate that the mineralogy of the study sandstones is dominated by quartz (>90%), with minor clay, and the presence of variable amounts of localized anhydrite as diagenetic nodular cements. The habitat of anhydrite nodules displays a substantial size variation, with nodules ranging from millimeters to several centimeters in scale. The larger nodules are easily identified visually in core samples and on borehole image logs. To investigate the origin of the anhydrite, sulfur and strontium isotope analysis were used to understand the relative timing of the nodule's development within the paragenetic sequence. Results from the sulfur and strontium isotopic analyses are consistent with the understanding that the anhydrite nodules are a late stage emplacement. A semi-quantitative "Anhydrite Abundance Index" (AAI) was calculated across key wells within the fields to establish the anhydrites regional distribution. The AAI uses the dry weight fraction of calcium and sulfur from geochemical logs to determine the volume of anhydrite. These volumes were further calibrated to volumes obtained through geochemical analysis of core samples, which is key to calculating the correct anhydrite volume required for formation evaluation. Regional distribution mapping created from this volume data suggests a widespread presence of the anhydrite nodular cementation. Understanding the relative abundance of anhydrite volumes is important when investigating the reservoir quality, especially if underestimating its presence may affect log-based porosity calculations and subsequently permeability calculations. The in-place quantification of the anhydrite nodular cement in 1D also enabled research to further the understanding of post-depositional, geochemical and geographic controls on the subsurface modelling and reservoir quality prediction.

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Kani, Tomomi, Yukio Isozaki, Keiji Misawa, Akira Ishikawa та Shigekazu Yoneda. "STABLE AND RADIOGENIC STRONTIUM ISOTOPE (δ88SR, 87SR /86SR) IN SEAWATER ACROSS GUADALUPIAN-LOPINGIAN BOUNDARY (PERMIAN)". У GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-299456.

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Su, Ni, Shouye Yang, Zhouyang Wu, Kai Deng, and Lei Bi. "A Reassessment of Radiogenic and Stable Strontium Isotope Systematics in Constraining Silicate and Carbonate Weathering Processes in Mountain Streams." In Goldschmidt2020. Geochemical Society, 2020. http://dx.doi.org/10.46427/gold2020.2481.

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