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Artículos de revistas sobre el tema "Stable isotopes geochemistry"

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Publicado: 25 de mayo de 2024

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1

Ogbesejana, Abiodun Busuyi, Bo Liu y Mehdi Ostadhassan. "Stable Isotope Geochemistry of the Organic Elements within Shales and Crude Oils: A Comprehensive Review". Molecules 27, n.º 1 (22 de diciembre de 2021): 34. http://dx.doi.org/10.3390/molecules27010034.

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Over time, stable isotopes have proven to be a useful tool in petroleum geochemistry. However, there is currently insufficient literature on stable isotope geochemistry of the organic elements within shales and crude oils in many petroleum systems around the world. As a result, this paper critically reviews the early and recent trends in stable isotope geochemistry of organic elements in shales and crude oils. The bulk and compound-specific stable isotopes of H, C, and S, as well as their uses as source facies, depositional environments, thermal maturity, geological age, and oil–oil and oil–source rock correlation studies, are all taken into account. The applications of the stable isotopes of H and C in gas exploration are also discussed. Then, the experimental and instrumental approaches to the stable isotopes of H, C, and S, are discussed.

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2

Pollard, A. M. "Isotopes and impact: a cautionary tale". Antiquity 85, n.º 328 (mayo de 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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3

Corfield, Richard M. y Richard D. Norris. "Isotope Paleobiology and Paleoecology: So Why Should Paleontologists Care About Geochemistry?" Paleontological Society Papers 4 (octubre de 1998): 1–6. http://dx.doi.org/10.1017/s1089332600000371.

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Stable isotopic techniques in geology illuminate not only variations in past climates and oceans, but also the life-histories of extinct animals, plants and protistans. This volume focuses on the ways that stable isotopes can be used as tracers of the fossil biology and ecology of long-dead organisms and ecosystems. Here, we introduce relevant aspects of stable isotope systematics and provide a summary of the papers collected in this volume. The nine contributions collected here, from some of the most eminent workers in their respective fields, explore aspects of the ecology, evolution and biology of organisms from planktonic foraminifera to dinosaurs.

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4

Farquhar, James. "Geochemistry of Non-Traditional Stable Isotopes". Geochimica et Cosmochimica Acta 69, n.º 11 (junio de 2005): 2947–48. http://dx.doi.org/10.1016/j.gca.2004.12.016.

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5

Tissot, François L. H. y Mauricio Ibañez-Mejia. "Unlocking the Single-Crystal Record of Heavy Stable Isotopes". Elements 17, n.º 6 (1 de diciembre de 2021): 389–94. http://dx.doi.org/10.2138/gselements.17.6.389.

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Stable isotopes provide deep insights into processes across a wide range of scales, from micron- to cosmic-size systems. Here, we review how continued advances in mass-spectrometry have enabled the analysis of ever-smaller samples and brought the field of heavy stable isotope geochemistry to its next frontier: the single-crystal scale. Accessing this record can be as enlightening as it is challenging. Drawing on novel systematics at different stages of development (from well-established to nascent), we discuss how the isotopes of heavy elements, such as magnesium, iron, zirconium, or uranium, can be used at the single-crystal and subcrystal scales to reconstruct magma thermal histories, crystal growth timescales, or, possibly, magma redox conditions.

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6

Aggarwal, Jugdeep, Judith Habicht-Mauche y Chelsey Juarez. "Application of heavy stable isotopes in forensic isotope geochemistry: A review". Applied Geochemistry 23, n.º 9 (septiembre de 2008): 2658–66. http://dx.doi.org/10.1016/j.apgeochem.2008.05.016.

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7

Alderton, David H. M. "Oxygen isotope fractionation between cassiterite and water". Mineralogical Magazine 53, n.º 371 (junio de 1989): 373–76. http://dx.doi.org/10.1180/minmag.1989.053.371.13.

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Analysis of stable isotopes in coexisting minerals has found wide application in the study of hydrothermal mineral deposits, particularly for elucidating the temperature and source of the fluid phase involved in mineralisation. For these purposes the temperature dependence of isotopic fractionation in several mineral-water systems has already been established (e.g. Friedman and O'Neil, 1977; O'Neil, 1986). Unfortunately, the oxygen isotope fractionation between cassiterite (SnO2) and water has not been adequately characterized, and this has hindered a full utilization of oxygen isotope data derived from studies of tin deposits (e.g. Harzer, 1970; Patterson et al., 1981; Kelly and Rye, 1979). Because of this situation, an attempt is made here to derive a relationship between temperature and the fractionation of oxygen isotopes (Δ) between quartz and cassiterite, based on the fractionations observed in naturally-occurring assemblages and independent temperature estimates.

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8

Ibañez-Mejia, Mauricio y François L. H. Tissot. "Reading the Isotopic Code of Heavy Elements". Elements 17, n.º 6 (1 de diciembre de 2021): 379–82. http://dx.doi.org/10.2138/gselements.17.6.379.

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The isotopic variability of the elements in our planet and Solar System is the end result of a complex mixture of processes, including variable production of isotopes in stars, ingrowth of daughter nuclides due to decay of radioactive parents, and selective incorporation of isotopes into solids, liquids, or gases as a function of their mass and/or nuclear volume. Interpreting the isotopic imprints that planetary formation and evolution have left in the rock and mineral record requires not only precise and accurate measurements but also an understanding of the drivers behind isotopic variability. Here, we introduce fundamental concepts needed to “read” the isotopic code, with particular emphasis on heavy stable isotope systems.

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9

Yang, Kunhua, Guilin Han, Man Liu, Xiaoqiang Li, Jinke Liu y Qian Zhang. "Spatial and Seasonal Variation of O and H Isotopes in the Jiulong River, Southeast China". Water 10, n.º 11 (17 de noviembre de 2018): 1677. http://dx.doi.org/10.3390/w10111677.

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The stable isotope technique of oxygen and hydrogen (δ18O and δ2H) and deuterium excess (d-excess) was used to investigate distribution characteristics in June 2017 and January 2018 in the Jiulong River, southeast China. The results revealed that (1) seasonal isotopic composition was mainly controlled by precipitation. It enriched lighter water isotopes in winter more than in summer because of the aggravating effect of low temperature and great rainfall. (2) Spatial distribution of the North, West, and South River showed increasing enrichment of heavy isotopes in that order. In the high-flow season, the continuous high-flow made δ18O and δ2H homogeneous, despite increasing weak evaporation along water-flow paths in the West and South River. In the low-flow season, there was a decreasing trend in the middle and lower reaches of the North and West main stream and an increasing trend in the South River. (3) O and H isotopic geochemistry exhibited natural and anthropogenic influence in hydrological process, such as heavy rainfall and cascade reservoirs. The results showed that O and H isotopes are indeed useful tracers of the water cycle.

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10

Burgess, Ray, Mitsuru Ebihara y Hans Eggenkamp. "Developments in Halogen Abundance and Isotope Measurements". Elements 18, n.º 1 (1 de febrero de 2022): 41–46. http://dx.doi.org/10.2138/gselements.18.1.41.

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The four stable halogens (F, Cl, Br, and I) are low-abundance elements that are widely distributed in nature. Two of the halogens, Cl and Br, each have two stable isotopes showing a range in natural isotope variation of up to a few parts per thousand. A variety of analytical techniques have been developed to determine the abundance and isotopic ratios of the halogens: these include in situ techniques for high spatial resolution studies and bulk determinations, and they have been applied to a range of materials, including whole rocks, minerals, glasses, and fluid inclusions. Here, we summarise some of the established methods for determining halogen abundances and isotopes and highlight key advances.

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11

Liu, Zhanmin, Congqiang Liu, Guilin Han, Zhongliang Wang, Zichen Xue, Zhaoliang Song y Cheng Yang. "Environmental geochemistry of calcium isotopes: Applications of a new stable isotope approach". Chinese Journal of Geochemistry 25, n.º 2 (abril de 2006): 184–94. http://dx.doi.org/10.1007/bf02872181.

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12

Volkman, John K. "Future Outlook for Applications of Biomarkers and Isotopes in Organic Geochemistry". Elements 18, n.º 2 (1 de abril de 2022): 115–20. http://dx.doi.org/10.2138/gselements.18.2.115.

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Organic geochemistry continues to make important contributions to our understanding of how the biogeochemistry of our planet and its environment has changed over time and of the role of human impacts today. This article provides a brief overview of the field and a perspective on how it might develop in the near future. Particular emphasis is placed on biomarkers (compounds with a distinctive chemical structure that can be related to specific organisms) and stable isotopes of carbon, hydrogen, and nitrogen, as these are major tools used by organic geochemists. Many geochemical studies involve a mixture of disciplines and so this article also focuses on how this research area can complement work in other fields.

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13

Eastoe, C. J. y J. M. Guilbert. "Stable chlorine isotopes in hydrothermal processes". Geochimica et Cosmochimica Acta 56, n.º 12 (diciembre de 1992): 4247–55. http://dx.doi.org/10.1016/0016-7037(92)90265-k.

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14

Baumgartner, L. P. y D. Rumble. "Transport of stable isotopes: I: Development of a kinetic continuum theory for stable isotope transport". Contributions to Mineralogy and Petrology 98, n.º 4 (abril de 1988): 417–30. http://dx.doi.org/10.1007/bf00372362.

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15

West, Catherine F. "Islands, Coastlines, and Stable Isotopes: Advances in Archaeology and Geochemistry". Journal of Island and Coastal Archaeology 8, n.º 2 (mayo de 2013): 149–51. http://dx.doi.org/10.1080/15564894.2013.803895.

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16

Feineman, Maureen, Sarah Penniston-Dorland, Franck Poitrasson y Stefan Weyer. "Applications of non-traditional stable isotopes in high-temperature geochemistry". Chemical Geology 258, n.º 1-2 (enero de 2009): 1–4. http://dx.doi.org/10.1016/j.chemgeo.2008.08.008.

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17

Nurgaliev, D. K., I. Yu Chernova, D. I. Khassanov, B. I. Gareev, G. A. Batalin y D. Ya Khabibullin. "Comparing the results of lineament analysis with isotope geochemistry data". SOCAR Proceedings, SI2 (30 de diciembre de 2021): 110–18. http://dx.doi.org/10.5510/ogp2021si200562.

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This article presents the results of a geochemical survey carried out in the southwestern part of the Siberian platform, within the Sayan-Yenisei (Angara) syneclise (a superorder Riphean-Middle Paleozoic structure). The object of research was hydrocarbon gases contained in the subsoil rocks (clays). The subsoil samples were taken from the bottom of boreholes (40 mm in diameter) made with an electric drill. The sampling depth was 0.6–1 m. Further laboratory studies included chromatographic and isotope analysis. Lineament analysis of the digital elevation model was carried out as a complementary study. One of the lineament analysis results was a lineament density map, which reflects the permeability (macro-fracture density) of the sedimentary cover. This allowed a comparison of the macro-fracture density with the gas content and isotopic composition. The study revealed that gases with a high content of heavy isotopes tend to gather in the low permeability areas. This can be explained by the fact that the gases disperse quickly within fractured zones, and deep gases should be expected only in the areas with strong cap rocks, i.e. in the areas with low macrofracture density where stable hydrocarbon deposits have already formed. Keywords: hydrocarbons; geochemical survey; isotope geochemistry; lineament analysis.

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18

Abudeif, Abdelbaset M., Gamal Z. Abdel Aal, Nessreen F. Abdelbaky, Mohamed H. Ali y Mohammed A. Mohammed. "An Integrated Geophysics and Isotope Geochemistry to Unveil the Groundwater Paleochannel in Abydos Historical Site, Egypt". Minerals 13, n.º 1 (30 de diciembre de 2022): 64. http://dx.doi.org/10.3390/min13010064.

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The scientific controversy among archaeologists about the existence of paleochannels under the Abydos archaeological site, Sohag, Egypt connecting the Osirion (cenotaph of Seti I) with the Nile River has been explained in this study. This study is an attempt to address this issue using integrating a near-surface geophysical approach with stable isotopic geochemistry on this site. Particularly, the stable oxygen and hydrogen isotopes on the water samples collected from the surface and the groundwater in the study area were analyzed and interpreted. The isotopes result showed that the Osirion water is a mixture of three different types of water: Old Nile Water (ONW) before the construction of the High Dam, Recent Nile Water (RNW) after the construction of the High Dam, and Paleowater (PW) from deeper aquifers. Field observations of the Osirion and nearby water cannot explain the presence and direction of this water. Therefore, the next step in this study is determining the location and the direction of the paleochannel connecting the Osirion with the Nile River which was proven using the electric resistivity tomography (ERT) technique. By using the results of the isotope of all types of water near the Osirion and its surrounding wells and the water of the Nile River, in addition to the near-surface geophysical measurements, the results indicated that the 3D view of the ERT data revealed a prospective paleochannel in the direction of the northeast and its location, where this channel is in charge of providing groundwater from the Nile River to the Osirion location.

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19

Pang, Zhonghe, Jie Li y Jiao Tian. "Noble gas geochemistry and chronology of groundwater in an active rift basin in central China". E3S Web of Conferences 98 (2019): 01040. http://dx.doi.org/10.1051/e3sconf/20199801040.

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Stable noble gas isotopes are excellent groundwater tracers. Radioactive noble gases are emerging new tools in the study of groundwater circulation dynamics. Among these, the 85Kr and 81Kr, and 39Ar have advanced very fast in recent years and exhibit strong potential in the reconstruction of the history of groundwater recharge and evolution in sedimentary basins at different scales. Here, we report the findings in groundwater circulation dynamics as relative to intensive water-rock interactions, heat transfer and He gas flux in Guanzhong Basin located in Xi’an, the geographical centre of China, which is a rift basin created by collision between the Eurasia and Indian plates, with active neotectonic activities. The recent technological breakthrough in noble gas isotope measurements, i.e. the atomic trap trace analysis (ATTA) techniques on Kr and Ar gas radionuclei, has revolutionized groundwater dating. Noble gas samples from shallow and deep wells to 3000 m depth have been collected to study isotope variations to reconstruct the history of groundwater recharge and understand the water-rock interaction processes. Stable isotopes of water show strong water-rock interaction in the formation, creating a strong positive O-isotope shift up to 10 ‰, a phenomenon that is rarely seen in a fairly low temperature environment. Analysis of 85Kr and 81Kr show groundwater ages up to 1.3 million years old along both North-South and a West-East cross sections, which offers strong evidence about the slow moving flow, strong water-rock interaction, rich geothermal resources as well as He gas resources.

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20

Ghosh, Santanu, Tushar Adsul, Balram Tiwari, Dinesh Kumar y Atul Kumar Varma. "Exploring Geochemical Signatures in Production Water: Insights from Coal Bed Methane and Shale Gas Exploration—A Brief Review". Methane 3, n.º 1 (4 de marzo de 2024): 172–90. http://dx.doi.org/10.3390/methane3010011.

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This article furnishes a brief review of the geochemistry of waters produced during coal bed methane and shale gas exploration. Stable deuterium and oxygen isotopes of produced waters, as well as the stable carbon isotope of dissolved inorganic carbon in these waters, are influenced by groundwater recharge, methanogenic pathways, the mixing of formation water with saline water, water–rock interactions, well completion, contamination from water from adjacent litho-units, and coal bed dewatering, among many others. Apart from the isotopic fingerprints, significant attention should be given to the chemistry of produced waters. These waters comprise natural saturated and aromatic organic functionalities, metals, radioisotopes, salts, inorganic ions, and synthetic chemicals introduced during hydraulic fracturing. Hence, to circumvent their adverse environmental effects, produced waters are treated with several technologies, like electro-coagulation, media filtration, the coupling of chemical precipitation and dissolved air flotation, electrochemical Fe+2/HClO oxidation, membrane distillation coupled with the walnut shell filtration, etc. Although produced water treatment incurs high costs, some of these techniques are economically feasible and sustain unconventional hydrocarbon exploitation.

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21

Huber, Miłosz A., Stanisław Hałas, Yuri N. Neradovsky, Tamara B. Bayanova, Artem W. Mokrushin y Lesia Lata. "Stable isotope geochemistry of sulfides from intrusion in Monchegorsk, northern part of Baltic Shield". Geochronometria 43, n.º 1 (1 de junio de 2016): 96–101. http://dx.doi.org/10.1515/geochr-2015-0034.

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Abstract The sulfide minerals from old mafic intrusion rocks from the Kola Peninsula were analyzed on stable sulfur isotopes. These samples were already dated by the Sm-Nd method. These sulfide samples were evaluated upon a geochemical composition by ICP-MS. The sulfide mineral samples were selected from the main ore-bearing rocks of the Monchetundra layered intrusion. The analyzed sulfides formed several generations of mineralization associated with primary and hydrothermal stage of formation of the deposits. Isotopic studies confirm a few consecutive stages of mineralization. These data were compared with the results of Sm-Nd dating of sulfide mineralization. The results of geochemical and geochronological studies indicate a complementarity in the context of determining the mineralization stages.

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22

Hatzinger, Paul B., John Karl Böhlke, Neil C. Sturchio, Baohua Gu, Linnea J. Heraty y Robert C. Borden. "Fractionation of stable isotopes in perchlorate and nitrate during in situ biodegradation in a sandy aquifer". Environmental Chemistry 6, n.º 1 (2009): 44. http://dx.doi.org/10.1071/en09008.

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Environmental context. Perchlorate (ClO4–) and nitrate (NO3–) are common co-contaminants in groundwater, with both natural and anthropogenic sources. Each of these compounds is biodegradable, so in situ enhanced bioremediation is one alternative for treating them in groundwater. Because bacteria typically fractionate isotopes during biodegradation, stable isotope analysis is increasingly used to distinguish this process from transport or mixing-related decreases in contaminant concentrations. However, for this technique to be useful in the field to monitor bioremediation progress, isotope fractionation must be quantified under relevant environmental conditions. In the present study, we quantify the apparent in situ fractionation effects for stable isotopes in ClO4– (Cl and O) and NO3– (N and O) resulting from biodegradation in an aquifer. Abstract. An in situ experiment was performed in a shallow alluvial aquifer in Maryland to quantify the fractionation of stable isotopes in perchlorate (Cl and O) and nitrate (N and O) during biodegradation. An emulsified soybean oil substrate that was previously injected into this aquifer provided the electron donor necessary for biological perchlorate reduction and denitrification. During the field experiment, groundwater extracted from an upgradient well was pumped into an injection well located within the in situ oil barrier, and then groundwater samples were withdrawn for the next 30 h. After correction for dilution (using Br– as a conservative tracer of the injectate), perchlorate concentrations decreased by 78% and nitrate concentrations decreased by 82% during the initial 8.6 h after the injection. The observed ratio of fractionation effects of O and Cl isotopes in perchlorate (ϵ18O/ϵ37Cl) was 2.6, which is similar to that observed in the laboratory using pure cultures (2.5). Denitrification by indigenous bacteria fractionated O and N isotopes in nitrate at a ratio of ~0.8 (ϵ18O/ϵ15N), which is within the range of values reported previously for denitrification. However, the magnitudes of the individual apparent in situ isotope fractionation effects for perchlorate and nitrate were appreciably smaller than those reported in homogeneous closed systems (0.2 to 0.6 times), even after adjustment for dilution. These results indicate that (1) isotope fractionation factor ratios (ϵ18O/ϵ37Cl, ϵ18O/ϵ15N) derived from homogeneous laboratory systems (e.g. pure culture studies) can be used qualitatively to confirm the occurrence of in situ biodegradation of both perchlorate and nitrate, but (2) the magnitudes of the individual apparent ϵ values cannot be used quantitatively to estimate the in situ extent of biodegradation of either anion.

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23

Druhan, Jennifer L. y Matthew J. Winnick. "Reactive Transport of Stable Isotopes". Elements 15, n.º 2 (1 de abril de 2019): 107–10. http://dx.doi.org/10.2138/gselements.15.2.107.

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24

Clarke, W. B., J. H. Crocket, R. J. Gillespie, H. R. Krouse, D. M. Shaw y H. P. Schwarcz. "Henry George Thode, M.B.E. 10 September 1910 — 22 March 1997". Biographical Memoirs of Fellows of the Royal Society 46 (enero de 2000): 499–514. http://dx.doi.org/10.1098/rsbm.1999.0098.

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Henry George Thode was one of Canada's most distinguished physical scientists, internationally known for his work in the fields of geochemistry and nuclear chemistry. He did much of the pioneering work on the separation and concentration of stable isotopes, and made seminal studies of the natural variations in the isotopic composition of the elements in nature, particularly sulphur. Morever, he was the principal force behind the development of McMaster University in Hamilton, Ontario, from a small church-affiliated liberal arts college with 600 students to one of Canada's leading universities with a renowned medical school and internationally recognized science and engineering faculties.

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25

Kyser, T. K. "Stable isotopes and fractionations in the mantle". Chemical Geology 70, n.º 1-2 (agosto de 1988): 184. http://dx.doi.org/10.1016/0009-2541(88)90742-5.

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26

Aarons, Sarah M., Aleisha C. Johnson y Shelby T. Rader. "Forming Earth’s Continental Crust: A Nontraditional Stable Isotope Perspective". Elements 17, n.º 6 (1 de diciembre de 2021): 413–18. http://dx.doi.org/10.2138/gselements.17.6.413.

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The formation of continental crust via plate tectonics strongly influences the physical and chemical characteristics of Earth’s surface and may be the key to Earth’s long-term habitability. However, continental crust formation is difficult to observe directly and is even more difficult to trace through time. Nontraditional stable isotopes have yielded significant insights into this process, leading to a new view both of Earth’s earliest continental crust and of what controls modern crustal generation. The stable isotope systems of titanium (Ti), zirconium (Zr), molybdenum (Mo), and thallium (Tl) have proven invaluable. Processes such as fractional crystallization, partial melting, geodynamic setting of magma generation, and magma cooling histories are examples of processes illuminated by these isotope systems.

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27

Mueller, M. H., R. Weingartner y C. Alewell. "Importance of vegetation, topography and flow paths for water transit times of base flow in alpine headwater catchments". Hydrology and Earth System Sciences 17, n.º 4 (30 de abril de 2013): 1661–79. http://dx.doi.org/10.5194/hess-17-1661-2013.

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Abstract. The mean transit time (MTT) of water in a catchment gives information about storage, flow paths, sources of water and thus also about retention and release of solutes in a catchment. To our knowledge there are only a few catchment studies on the influence of vegetation cover changes on base flow MTTs. The main changes in vegetation cover in the Swiss Alps are massive shrub encroachment and forest expansion into formerly open habitats. Four small and relatively steep headwater catchments in the Swiss Alps (Ursern Valley) were investigated to relate different vegetation cover to water transit times. Time series of water stable isotopes were used to calculate MTTs. The high temporal variation of the stable isotope signals in precipitation was strongly dampened in stream base flow samples. MTTs of the four catchments were 70 to 102 weeks. The strong dampening of the stable isotope input signal as well as stream water geochemistry points to deeper flow paths and mixing of waters of different ages at the catchments' outlets. MTTs were neither related to topographic indices nor vegetation cover. The major part of the quickly infiltrating precipitation likely percolates through fractured and partially karstified deeper rock zones, which increases the control of bedrock flow paths on MTT. Snow accumulation and the timing of its melt play an important role for stable isotope dynamics during spring and early summer. We conclude that, in mountainous headwater catchments with relatively shallow soil layers, the hydrogeological and geochemical patterns (i.e. geochemistry, porosity and hydraulic conductivity of rocks) and snow dynamics influence storage, mixing and release of water in a stronger way than vegetation cover or topography do.

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28

Pack, Andreas, Stephan Hoernes, Matthias Göbbels, Rainer Bross y Andreas Buhr. "Stable oxygen isotopes - A new approach for tracing the origin of oxide inclusions in steels". European Journal of Mineralogy 17, n.º 3 (14 de junio de 2005): 483–93. http://dx.doi.org/10.1127/0935-1221/2005/0017-0483.

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29

Cameron, Eion M. "Stable isotopes in high temperature geological processes". Journal of Geochemical Exploration 30, n.º 1-3 (enero de 1988): 323–24. http://dx.doi.org/10.1016/0375-6742(88)90067-2.

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30

Anbar, A. D. "Iron stable isotopes: beyond biosignatures". Earth and Planetary Science Letters 217, n.º 3-4 (enero de 2004): 223–36. http://dx.doi.org/10.1016/s0012-821x(03)00572-7.

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31

Magette, Evan, Adam Turner, Yongbo Peng y Achim D. Herrmann. "Syndepositional Uptake of Uranium, Molybdenum and Vanadium into Modern Bahamian Carbonate Sediments during Early Diagenesis". Geosciences 13, n.º 3 (26 de febrero de 2023): 66. http://dx.doi.org/10.3390/geosciences13030066.

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Syndepositional diagenesis is a complicating factor when interpreting geochemical proxies in carbonate sedimentary environments. Previous studies have suggested that carbonate deposits may preserve the geochemical and isotopic signatures of seawater that can be used for paleo-redox reconstructions. However, more work is necessary to understand how these trace metals are preserved. The present study examines shallow marine carbonate sediments from the Bahamas to better understand diagenetic effects on trace metal uptake and sequestration. Analysis of diagenetic effects and trace metal uptake follows a multi-method approach, combining sequential extraction, stable isotope analyses, and rare earth elemental analysis. Stable isotopes track bacterial sulfate reduction, denitrification, and organic matter source and provide insight into thresholds and processes for the authigenic trace metal uptake. Importantly, exchangeable phases exhibit authigenic accumulation of molybdenum, uranium and vanadium, and intensified bacterial sulfate reduction is evidenced by most depleted sulfur isotope signatures. In addition, rare earth element values are very indicative proxies that suggest altered primary seawater trace element in carbonates (no cerium or lanthanum anomaly, moderate heavy rare earth element enrichment, decreased y/ho ratios and positive correlations between aluminum, manganese, and iron). Taken together, these results allow the development of a framework to better understand how to apply sedimentary geochemistry of carbonate rocks to paleo-environments as this study shows significant authigenic accumulation of redox-sensitive trace metals by exchangeable phases.

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32

Pracht, Hilde, Brett Metcalfe y Frank J. C. Peeters. "Oxygen isotope composition of the final chamber of planktic foraminifera provides evidence of vertical migration and depth-integrated growth". Biogeosciences 16, n.º 2 (1 de febrero de 2019): 643–61. http://dx.doi.org/10.5194/bg-16-643-2019.

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Abstract. The translation of the original seawater signal (i.e. ambient temperature and δ18Osw) into distinct chambers of a single shell of a foraminifer during calcification can influence our interpretation of surface ocean conditions of the past, when based upon oxygen and carbon stable isotope geochemistry. In this study three different hypotheses were tested to gain more insight into biological and ecological processes that influence the resultant composition of stable isotopes of oxygen (δ18O) in the shells of planktonic foraminifera. These hypotheses were related to the shell size; the differences in isotopic composition between the final chamber and the remaining shell; and the differences between different species. Shells of Trilobatus sacculifer, Globigerinoides ruber white and Neogloboquadrina dutertrei were picked from the top of multi-core GS07-150-24, of modern age, offshore of north-eastern Brazil (3∘46.474′ S, 37∘03.849′ W) and analysed for single-shell and single-chamber stable isotope analysis. We show that the mean value of δ18O of the final chambers (δ18OF) is 0.2 ‰ ± 0.4 ‰ (1σ) higher than the mean value δ18O of the test minus the final chamber (δ18O<F) of T. sacculifer. The formation of the final chamber happens at temperatures that are approximately 1 ∘C cooler than the chambers formed prior, suggesting both ontogenetic depth migration to deeper water and a potential offset from the surface signal. Furthermore, we show that there is no statistical difference in the δ18Osacculifer values of shells of three different size classes of T. sacculifer, although the pattern between the different size classes indicates depth migration during the life and growth of T. sacculifer. Comparison of vital effect corrected δ18Oshell between T. sacculifer, G. ruber white and N. dutertrei suggests that G. ruber has a slightly shallower depth habitat (∼90–120 m) compared to the other two species (∼100–130 m). Disentangling depth vs. seasonal habitat is complicated given the commonality between isotope values from similar depths but different seasons; for instance, the same average isotope value will have a shallower depth habitat in May than September. Calculation of seasonal-depth habitat was therefore tested. Our results highlight the complicated nature of interpreting oxygen isotopes even for the modern record.

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33

Chela-Flores, J. "A case for landing on the moon's farside to test nitrogen abundances". International Journal of Astrobiology 11, n.º 1 (29 de noviembre de 2011): 61–69. http://dx.doi.org/10.1017/s1473550411000334.

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AbstractA high research priority in astrobiology is the search and eventual identification of biomarkers in the Solar System. In spite of numerous steps forward, lunar science remains largely disjoint from the main stream of astrobiology, but in recent years the Moon has begun to emerge as a novel target for astrobiologists. We discuss an overlap between lunar geology and terrestrial geomicrobiology that arises from analysis of lunar soils and some uncertainties in chemical evolution and the origin of life scenarios. Unexpected isotopic heterogeneity of nitrogen (N) was found to be remarkable in samples from Apollo and the Luna programme. Both the stable isotope geochemical data of the biogenic elements, as well as the noble gases trapped in lunar soils added valuable new and relevant data. These discoveries are potential sources of information on early Earth evolution. The elusive ratio of N's two stable isotopes 15N/14N has played a fundamental role in this research. The analysis of individual grains of ilmenite suggests that 90% of all the trapped N does not originate from solar wind (SW). We discuss the significance of these stable isotopes from the point of view of astrobiology in the light of the next generation of lunar exploration. We underline the high priority of testing the origin of non-solar N source trapped in the regolith of the lunar farside. In the proposals of new lunar missions, the characterization of the geochemistry at several lunar sites is a major objective. Some arguments are presented in favour of using novel space technologies in a search for biomarkers in geographical distinct lunar landing sites. We restrict our attention to one aspect of the science requirements for the forthcoming missions by focusing on a very limited objective: to take a closer look at the geochemical characterization of the chemical element N on the soils of the lunar farside.

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34

Aléon, Jérôme, Marc Chaussidon, Michel Champenois y Denis Mangin. "Quantitative Imaging of Stable Isotopes by Ion Microprobe". Geostandards and Geoanalytical Research 25, n.º 2-3 (diciembre de 2001): 417–29. http://dx.doi.org/10.1111/j.1751-908x.2001.tb00998.x.

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35

HARLEY, S. L. y C. M. GRAHAM. "Stable isotopes as tracers of metamorphic processes: introduction". Journal of Metamorphic Geology 12, n.º 3 (mayo de 1994): 209–10. http://dx.doi.org/10.1111/j.1525-1314.1994.tb00016.x.

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36

Clark, Ian D. y Bernard Lauriol. "Kinetic enrichment of stable isotopes in cryogenic calcites". Chemical Geology 102, n.º 1-4 (diciembre de 1992): 217–28. http://dx.doi.org/10.1016/0009-2541(92)90157-z.

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37

Ray, Jyotiranjan S. y R. Ramesh. "Rayleigh fractionation of stable isotopes from a multicomponent source". Geochimica et Cosmochimica Acta 64, n.º 2 (enero de 2000): 299–306. http://dx.doi.org/10.1016/s0016-7037(99)00181-7.

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38

Youke, Han y An Na. "An approach to analysis of stable isotopes in microsamples". Chinese Journal of Geochemistry 10, n.º 4 (octubre de 1991): 372–78. http://dx.doi.org/10.1007/bf02841098.

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39

Green, Daniel R., Tanya M. Smith, Gregory M. Green, Felicitas B. Bidlack, Paul Tafforeau y Albert S. Colman. "Quantitative reconstruction of seasonality from stable isotopes in teeth". Geochimica et Cosmochimica Acta 235 (agosto de 2018): 483–504. http://dx.doi.org/10.1016/j.gca.2018.06.013.

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40

Hansen, Hans Jørgen. "Stable isotopes of carbon from basaltic rocks and their possible relation to atmospheric isotope excursions". Lithos 92, n.º 1-2 (noviembre de 2006): 105–16. http://dx.doi.org/10.1016/j.lithos.2006.03.029.

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41

Xia, Di, Han Ye, Yingying Xie, Chengfang Yang, Meiqin Chen, Zhi Dang, Xiaoyun Yi y Guining Lu. "Isotope geochemistry, hydrochemistry, and mineralogy of a river affected by acid mine drainage in a mining area, South China". RSC Advances 7, n.º 68 (2017): 43310–18. http://dx.doi.org/10.1039/c7ra07809a.

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42

Crumpton-Banks, Jessica G. M., Thomas Tanner, Ivan Hernández Almeida, James W. B. Rae y Heather Stoll. "Technical note: No impact of alkenone extraction on foraminiferal stable isotope, trace element and boron isotope geochemistry". Biogeosciences 19, n.º 24 (14 de diciembre de 2022): 5633–44. http://dx.doi.org/10.5194/bg-19-5633-2022.

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Abstract. Recent advances in geochemical techniques mean that several robust proxies now exist to determine the past carbonate chemistry of the oceans. Foraminiferal δ11B and alkenone carbon isotopes allow us to reconstruct sea-surface pH and pCO2, respectively, and the ability to apply both proxies to the same sediment sample would give strongly paired datasets and reduce sample waste. However, no studies to date have examined whether the solvents and extraction techniques used to prepare alkenones for analysis also impact the geochemistry of foraminifera within those sediments. Here we examine six species pairs of planktic foraminifera, with half being taken from non-treated sediments and half being taken from sediments where alkenones have been extracted. We look for visual signs of contrasting preservation and compare analyses of δ18O, δ13C, δ11B and trace elements (Li, B, Na, Mn, Mg, Sr and U/Ca). We find no consistent geochemical offset between the treatments and excellent agreement in δ11B measurements between them. Our results show that boron isotope reconstructions of pH in foraminifera from alkenone-extracted sediments can be applied with confidence.

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43

Laeter, John R. "The Role of Isotopic Reference Materials for the Analysis of "Non-Traditional" Stable Isotopes". Geostandards and Geoanalytical Research 29, n.º 1 (marzo de 2005): 53–61. http://dx.doi.org/10.1111/j.1751-908x.2005.tb00655.x.

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44

Luther, George W. "Stable isotopes: Natural and anthropogenic sulphur in the environment". Chemical Geology 103, n.º 1-4 (enero de 1993): 295–96. http://dx.doi.org/10.1016/0009-2541(93)90310-f.

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45

Ibrahim, Khalil, Issa Makhlouf, Ali El Naqah y Sana’ Al-Thawabteh. "Geochemistry and Stable Isotopes of Travertine from Jordan Valley and Dead Sea Areas". Minerals 7, n.º 5 (22 de mayo de 2017): 82. http://dx.doi.org/10.3390/min7050082.

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46

Garnit, Hechmi, Maria Boni, Giuliana Buongiovanni, Giuseppe Arfè, Nicola Mondillo, Michael Joachimski, Salah Bouhlel y Giuseppina Balassone. "C–O Stable Isotopes Geochemistry of Tunisian Nonsulfide Zinc Deposits: A First Look". Minerals 8, n.º 1 (9 de enero de 2018): 13. http://dx.doi.org/10.3390/min8010013.

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47

Gammons, C. H., D. M. Snyder, S. R. Poulson y K. Petritz. "Geochemistry and Stable Isotopes of the Flooded Underground Mine Workings of Butte, Montana". Economic Geology 104, n.º 8 (1 de diciembre de 2009): 1213–34. http://dx.doi.org/10.2113/gsecongeo.104.8.1213.

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48

Philp, R. Paul. "The emergence of stable isotopes in environmental and forensic geochemistry studies: a review". Environmental Chemistry Letters 5, n.º 2 (16 de agosto de 2006): 57–66. http://dx.doi.org/10.1007/s10311-006-0081-y.

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49

Albarède, Francis. "Metal Stable Isotopes in the Human Body: A Tribute of Geochemistry to Medicine". Elements 11, n.º 4 (agosto de 2015): 265–69. http://dx.doi.org/10.2113/gselements.11.4.265.

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50

Meyer, H. y R. S. Sletten. "Preface to the special issue on stable isotopes and geochemistry of ground ice". Permafrost and Periglacial Processes 22, n.º 1 (enero de 2011): 1–2. http://dx.doi.org/10.1002/ppp.718.

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