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Literatura académica sobre el tema "Stable isotopes geochemistry"

Autor: Grafiati

Publicado: 25 de mayo de 2024

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Artículos de revistas sobre el tema "Stable isotopes geochemistry"

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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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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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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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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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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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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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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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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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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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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Tesis sobre el tema "Stable isotopes geochemistry"

Valdes, Maria. "Geochemistry and Cosmochemistry of Calcium Stable Isotopes". Doctoral thesis, Universite Libre de Bruxelles, 2018. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/276866.

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Calcium (Ca) is the fifth most abundant element in the rocky planets. As a lithophile, refractory element, Ca does not partition into planetary cores nor is it volatilized during planetary accretion. These characteristics make Ca ideal for investigating the earliest stages of planetary formation and the subsequent chemical evolution of planetary mantles and crusts. This thesis presents observations of and explores the mechanisms involved in high-temperature mass-dependent Ca isotope fractionation in terrestrial, lunar, and meteoritic material. Chapter 1 reports Ca isotope fractionation among a co-genetic suite of samples from the Guelb el Azib ultramafic-mafic-anorthosite complex, which represents the fractional crystallization sequence of a terrestrial igneous magma chamber. The measurements imply that Ca isotope fractionation in an evolving crystallizing magma is mineralogically controlled and that the degree of fractionation can vary according to the Ca composition of the residual magma. Chapter 2 investigates ureilites, a distinctive group of achondritic meteorites, widely regarded to be mantle remnants of a disrupted asteroidal parent body. To date, it is not clear which of their features were inherited from the original chondritic body and which were created during post-accretionary igneous processes such as partial melting. This chapter presents evidence that partial melting on the ureilite parent body is responsible for two such ambiguous characteristics, Ca isotopic and magnesium number (Mg
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Gilmour, Iain. "The distribution of carbon stable isotopes within sedimentary organic matter". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373660.

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Morisset, Natalie Carleton University Dissertation Geology. "Stableisotope and radioisotope geochemistry of the Panda Hill carbonatite, Tanzania". Ottawa, 1992.

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Engström, Emma. "Fractionation of the stable silicon isotopes : analytical method developments and selected applications in geochemistry". Licentiate thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18719.

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During the last few decades, variations in the 'natural' isotopic abundances of stable elements (termed 'fractionation') have received considerable interest from the scientific community. Though analytical methods and techniques for the measurement of isotopic abundances with adequate figures of merit have been available for light elements (e.g. B, C, N and O) for some time, and the wealth of data produced has secured maturity status for such applications, relatively modest progress in fractionation studies devoted to high-mass elements has been made until recently, mainly because of constraints of the available analytical techniques. The situation has changed drastically with the advent of multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), with the number of reports about natural fractionation of Fe, Cu, Zn, Mo, Cd, Sn increasing exponentially during the recent years. In spite of the high Si abundance in nature and the importance of the element in many areas of the Earth sciences (focusing on e.g. weathering, the global Si cycle, paleoclimate studies, paleoceanography, and biological uptake), the available information on Si isotope fractionation remains rather limited due to the laborious and hazardous chemical purification procedures associated with the analyses. The focus of this thesis was the development of analytical methods for the precise and accurate measurements of Si isotope ratios, which is an absolute requirement for meaningful fractionation studies, in various matrices. This work involved detailed studies on sample preparation (including matrix separation) and refining the measurement protocol by using high resolution MC-ICP-MS. In the former stages, quantitative analyte recovery, thorough control of contamination levels and purification efficiency were the major targets, while severe spectral interferences and the need for adequate instrumental mass bias corrections challenged the latter. The performance of the method was tested in the first inter- laboratory performance assessment study of its kind with good results. As limited examples of applications, studies on Si isotope fractionation in aqueous, plant and humus samples were performed utilizing methods developed. The efficient analyte separation, high-resolution capability of the instrument, quantitative Si recovery and accurate mass bias correction using Mg as internal standard, allowed the determination of the Si isotopic composition of natural waters and biological samples with long-term reproducibility, expressed as twice the standard deviation (2σ), equal to or less than 0.10‰ for δ29Si and 0.25‰ for δ30Si. Furthermore, the presence of a challenging spectral interference on 29Si originating from 28SiH+ was revealed during this study, indicating that instrumental resolution in excess of 3500 is required for interference-free Si isotopic analyses. However, despite complete removal of N-, O-, and C-containing interferences appearing on the high-mass side of the Si isotopes, it was found that exact matching of both the acid matrix and the Si concentration are mandatory due to tailing from the abundant 14N16O+ interference on 30Si. This thesis also includes results from the first study of the Si isotopic homogeneity of major biomass components from a defined area in Northern Sweden covered by boreal forest. Since the potential impact of vegetation on the terrestrial biogeochemical cycle has attracted considerable interest, thorough characterization of the Si isotopic composition of the biomass potentially allows the utilization of this isotope system in the assessment of the relative contributions of biogenic and mineral silica in plants, soil solutions and natural waters (including fresh-, brackish- and marine waters). Isotopic analyses of the biological materials yielded a surprisingly homogenous silicon isotopic composition (relative to the NBS28 Si reference material), expressed as δ29Si (2σ), ranging from (- 0.14 ± 0.05)‰ to (0.13 ± 0.04)‰ Furthermore, elemental and isotopic analysis of local airborne particulate matter suggests that vegetation also accumulates silica via incorporation of exogenous Si containing primary and secondary minerals (in addition to root uptake of non-ionic silicic acid), a fact that has been neglected in previously published studies. This strongly indicates that the presence of potential surface contributions must be considered during in situ silicon uptake studies

Godkänd; 2007; 20071011 (ysko)

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Kelly, Jennifer Christine. "The fluid evolution of the Mount Mica and Irish Pit pegmatites, Maine| Evidence from stable isotopes". California State University, Long Beach, 2013.

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Negonga, Lisias. "Geochemistry, stable isotopes and fluid inclusion studies of the Otjikoto gold deposit, Central Namibia". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29190.

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The Otjikoto gold deposit is located within the Damara Orogenic Belt which is part of the system of Pan-African mobile belts. The Damara Belt is a northwest trending orogenic belt which formed through sequences of spreading, rifting, subduction and from continental collision between the Congo, Kalahari and Rio Delta Plata Cratons between 900 Ma and 450 Ma. Mineralisation at Otjikoto is hosted by a group of metamorphic rocks which consist of biotite schists from the Okonguarri Formation, albitites from the Oberwasser member and marble units from the Okawayo member. The gold mineralization occurs in a sheeted vein network system with veins which are positioned parallel towards the foliation of the albitites and hornfels of the Oberwasser Member. The vein types include both quartz and carbonate hosted vein types. The vein mineralogy includes magnetite, pyrite and pyrrhotite which are associated with amphibole, quartz, almandine garnets, and free gold. A fluid inclusion study carried out on the vein quartz showed the co-existence of the aqueous, carbonic and aqueouscarbonic fluid inclusions within the Okonguarri Formation. The aqueous inclusions have moderate to high salinities with salinities ranging from 30.0 to 44.5 wt. % NaCl eq. in aqueous inclusions with halite crystals and from 0.9 to 22.9 wt. % NaCl eq. in inclusions without halite crystals. The total homogenisation temperatures, Th tot (L), ranged from 151 to 488 °C in the aqueous-carbonic inclusions and from 156 to 444 °C in the aqueous inclusions. The melting temperature of CO2 (TmCO2) ranged from -60.3 to -57.5 °C in carbonic inclusions and from - 60.2 to -57.2 °C in aqueous-carbonic inclusions. It is proposed that the aqueous and carbonic inclusions (CO2-CH4) from the Okonguarri Formation are the end members of fluid immiscibility. The presence of CO2 and CH4 is indicated by the low TmCO2 values and may be justified by the decomposition of the carbonaceous metasediments which are found in the stratigraphy at Otjikoto. The δ 18O values range from of 8.35 ‰ to 8.75 ‰ for the magnetite and 17.51 ‰ to 18.47 ‰ for the vein quartz samples. Analysis of the microprobe data on the amphiboles shows that the analysed grains are made up of anthophyllites. Microprobe data of the chlorites showed that the majority of the chlorites are made up of ripidolites. Temperatures of chlorite formation were calculated to be in the range of 221°C to 358 °C by using chlorite geothermometric equations. Major element variation diagrams show a strong negative correlation of TiO2, Al2O3, MgO, Na2O and FeOt vs SiO2. Variation diagrams were also plotted for the trace elements vs Zr. The Sr, Y, La and Ce vs Zr plots show a strong positive correlation.

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Gall, Louise. "Development and application of nickel stable isotopes as a new geochemical tracer". Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ebe3c3e1-0b1b-49ed-b64a-016c8d76f220.

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In this thesis, I have developed a new methodology for the accurate determination of mass-dependent variations in nickel (Ni) isotope compositions. Nickel is initially separated in a three-column ion-exchange procedure, and the purified solutions are analysed by multi-collector inductively coupled plasma mass spectrometry (MCICPMS) using a double-spike technique. Using this methodology, I have measured the first Ni isotope ratios for a wide variety of natural geological samples. Significant Ni isotope variations were observed, with an overall spread in delta 60Ni-values of -0.9 to 2.5 permil. In igneous rocks Ni isotopes appear to be largely homogeneous, with only small variations (0.2 permil) between different rock types. Weathering of silicate rocks does on the other hand appear to cause significant fractionation of Ni isotopes, probably producing an isotopically heavy riverine input to the ocean. A heavy isotope signature is also visible in hydrogenetic ferromanganese crusts, with surface scrapings from globally distributed crusts show an average delta 60Ni-value of 1.65 permil. However, the variation in these samples is over 1.5 permil, likely reflecting local sources or biological processes, or alternatively indicating a heterogeneous Ni isotopic composition of the ocean. Organic-rich sediments also show heavy isotopic compositions, which are possibly transferred to the crude oils originating in these types of sediments. The only significant reservoir of light Ni isotopes found during this project are sulphides from magmatic systems. Overall, this thesis demonstrates the potential of this system as a powerful new tracer for a variety of geochemical processes.

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Brown, Elizabeth Ann. "Taxonomy and Geochemistry of the Globigerinoides ruber-elongatus Plexus, with Paleontological Implications". Scholar Commons, 2011. https://scholarcommons.usf.edu/etd/7479.

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The reliability of foraminifera as stratigraphic index fossils, and as isotopic proxies of marine environments, is based on the assumption that the fossil concepts represent uniform species, responding consistently to their ambient environments. Understanding sources of uncertainty is, therefore, critical. In this dissertation, I explore a potential bias in the application of planktonic foraminifera utilized extensively for Cenozoic paleo-reconstruction and, to a lesser extent, biostratigraphy: the Globigerinoides ruber-elongatus plexus (‘plexus’ meaning a complex network of interconnected members). Taxonomic revisions since 1826 have resulted in the merging of multiple Globigerinoides species names under one general designation (“Globigerinoides ruber”), the implications of which are now under scrutiny. These “morphotypes” of G. ruber have been shown to incorporate stable isotopes and trace elements in seawater dissimilarly, and correspond to multiple genetic species, some of which occupy different environments. Various criteria exist to sub-divide, group, or distinguish members of the Globigerinoides plexus, most notably the recurring use of Globigerinoides elongatus as a less spherical, less symmetrical counterpart to G. ruber. But the efficacy of these various taxonomic criteria has not been tested quantitatively. Most rely on the traits of visually distinctive “end-members,” while specimens in the morphological “transitional zone” are left to an observer’s subjective interpretation. This prevents quantification in census counts, and may lead to erroneous geochemical analyses. Furthermore, molecular clock estimates suggest that the G. elongatus species evolved significantly later than G. ruber, affecting its potential as a biomarker. In this dissertation, I examine the potential of a minimal-criteria system for classifying Globigerinoides-type morphologies using only three conditions: final chamber compression, final chamber asymmetry, and aperture compression. Morphometric analyses on specimens grouped according to this new system allow us to assess to what degree visual classification reflects morphospace discontinuity. Armed with this information, I then explore potential isotopic offsets between members of the Globigerinoides plexus, and its use in reconstructing regional differences in climate or habitat influences in the Gulf of Mexico and Caribbean basins. Finally, having shown that G. ruber and G. elongatus can be reliably visually distinguished, I tracked the species’ fossil presence individually in a deep core from the South China Sea, and confirmed the presence of G. ruber in the South China Sea through the late Miocene, and G. elongatus through the Pleistocene. While it is believed that neither species was traced to its true first occurrence (FO), the relative FO of G. ruber was shown to be 4–5 Ma before G. elongatus

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Saquet, Michelle. "Greenhouse gas flux and budget from an experimentally flooded wetland using stable isotopes and geochemistry". Thesis, University of Waterloo, 2003. http://hdl.handle.net/10012/1249.

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A boreal forest wetland (L979) was flooded in 1993 at the Experimental Lakes Area, Ontario to imitate a hydroelectric reservoir and to study the effects of flooding on greenhouse gas production and emission. Flooding initially caused CO₂ and CH4 emission rates to increase and changed the wetland from a small, natural carbon sink to a large source of carbon. The increased production of greenhouse gases in the peatland also caused the majority of the peat to float to the surface creating floating peat islands, within 4 years of flooding. The floating peat islands are a larger source than the central pond of CH4 to the atmosphere due to the high water table and small oxidation zone as compared to the earlier undisturbed peatland. The floating peat islands had an average flux of 202 ± 66 mg C-CH4/m²/day comparable to rates measured in 1995. Methane flux rates are spatially and temporally variable ranging from ?117 to 3430 mg C-CH4/m²/day. The variability is partly due to episodic releases of gas bubbles and changes in overlying pressure from the water table. The development of floating peat islands created an underlying water pocket. The water pocket increased water movement between the central pond and the peatland and led to increased peat temperatures and methane oxidation, and removal of debris from the water pocket. DIC, CH4, and O₂ concentrations, and δ13C-DIC, δ13-CH4, and δ18O-O₂ values in the water pocket were similar to values in the central pond. Before flooding, the δ13C-CH4 values from the peatland ranged between ?36 and ?72? indicating that about 65 to 90% of the methane was oxidized before flooding. After flooding, the median δ13C-CH4 value from the floating peat islands was ?52? indicating that about 30% of the methane was oxidized before it was emitted to the atmosphere. Since the floating islands are now vegetated, photosynthesis and transport via plants allow the movement of oxygen into the peat islands Methane oxidation in the central pond was similar in 2001 and 2002. DIC and CH4 isotope mass budgets from June 3 to September 23, 2002 indicate that inputs were smaller than outputs at L979. Calculated net DIC and CH4 production in the central pond was 8490 and 432 kg C, with δ13C-DIC of -18. 5 ? and δ13C-CH4 of -32. 5?. Decomposition of peat was the source of DIC and CH4. O₂ saturation levels indicate that the pond is always undersaturated and that respiration dominates the system; however, the δ18O-O₂ also indicates that photosynthesis is an important process in the central pond of L979. The peat islands contributed about 90% of the total CH4 flux, whereas the open water areas contributed 10%. This indicates that formation of peat islands in a hydroelectric area can significantly affect the greenhouse gas emissions to the atmosphere. The average flux of CH4 from the entire wetland in 2002 was 202 ± 77 mg C-CH4/m²/day, equivalent to 44 ± 17 g C-CH4/m²/year (year = 220 days). This is higher than preflood values of 0. 5 g C-CH4/m²/year in 1992, and the early post-flood value of 8. 9 g C-CH4/m²/year in 1993/1994. The wetland continues to emit methane after ten years of flooding at higher than preflood rates.

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Freimuth, Erika Jacob. "Advancing Leaf Wax Paleohydrology: From Plant Source to Sediment Sink". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1535381306803793.

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Libros sobre el tema "Stable isotopes geochemistry"

W, Valley John, Cole David R y Mineralogical Society of America, eds. Stable isotope geochemistry. Washington, D.C: Mineralogical Society of America, 2001.

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Stable isotope geochemistry. 4^a ed. Berlin: Springer, 1997.

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Stable isotope geochemistry. 5^a ed. Berlin: Springer, 2004.

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Stable isotope geochemistry. 3^a ed. Berlin: Springer-Verlag, 1987.

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M, Johnson Clark, Beard Brian L, Albarède Francis, American Geophysical Union Meeting y Canadian Geophysical Union Meeting, eds. Geochemistry of non-traditional stable isotopes. Washington, DC: Mineralogical Society of America, 2004.

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Eggenkamp, Hans. The Geochemistry of Stable Chlorine and Bromine Isotopes. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-28506-6.

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Mora, Claudia I. Geochemistry and stable isotopes of paleosols: A Geological Society of America continuing education short course, October 24, 1993. Knoxville: University of Tennessee, Dept. of Geological Sciences, 1993.

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Hoefs, Jochen. Stable Isotope Geochemistry. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77692-3.

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Hoefs, Jochen. Stable Isotope Geochemistry. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-05406-2.

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Hoefs, Jochen. Stable Isotope Geochemistry. Berlin, Heidelberg: Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-662-09998-8.

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Capítulos de libros sobre el tema "Stable isotopes geochemistry"

Canfield, D. E. "12. Biogeochemistry of Sulfur Isotopes". En Stable Isotope Geochemistry, editado por John W. Valley y David R. Cole, 607–36. Berlin, Boston: De Gruyter, 2001. http://dx.doi.org/10.1515/9781501508745-015.

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Hayes, John M. "3. Fractionation of Carbon and Hydrogen Isotopes in Biosynthetic Processes". En Stable Isotope Geochemistry, editado por John W. Valley y David R. Cole, 225–78. Berlin, Boston: De Gruyter, 2001. http://dx.doi.org/10.1515/9781501508745-006.

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Heuser, Alexander. "Biomedical Application of Ca Stable Isotopes". En Calcium Stable Isotope Geochemistry, 247–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-540-68953-9_8.

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Shanks, W. C. "8. Stable Isotopes in Seafloor Hydrothermal Systems: Vent fluids, hydrothermal deposits, hydrothermal alteration, and microbial processes". En Stable Isotope Geochemistry, editado por John W. Valley y David R. Cole, 469–526. Berlin, Boston: De Gruyter, 2001. http://dx.doi.org/10.1515/9781501508745-011.

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Blum, Joel D. "Applications of Stable Mercury Isotopes to Biogeochemistry". En Advances in Isotope Geochemistry, 229–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-10637-8_12.

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Anbar, Ariel D. "12. Molybdenum Stable Isotopes: Observations, Interpretations and Directions". En Geochemistry of Non-Traditional Stable Isotopes, editado por Clark M. Johnson, Brian L. Beard y Francis Albarède, 429–56. Berlin, Boston: De Gruyter, 2004. http://dx.doi.org/10.1515/9781501509360-016.

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Philp, R. Paul y Guillermo Lo Monaco. "Applications of Stable Isotopes in Hydrocarbon Exploration and Environmental Forensics". En Advances in Isotope Geochemistry, 639–77. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-10637-8_31.

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Schauble, Edwin A. "3. Applying Stable Isotope Fractionation Theory to New Systems". En Geochemistry of Non-Traditional Stable Isotopes, editado por Clark M. Johnson, Brian L. Beard y Francis Albarède, 65–112. Berlin, Boston: De Gruyter, 2004. http://dx.doi.org/10.1515/9781501509360-006.

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Albarède, Francis. "11. The Stable Isotope Geochemistry of Copper and Zinc". En Geochemistry of Non-Traditional Stable Isotopes, editado por Clark M. Johnson, Brian L. Beard y Francis Albarède, 409–28. Berlin, Boston: De Gruyter, 2004. http://dx.doi.org/10.1515/9781501509360-015.

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Stewart, Michael A. y Arthur J. Spivack. "7. The Stable-Chlorine Isotope Compositions of Natural and Anthropogenic Materials". En Geochemistry of Non-Traditional Stable Isotopes, editado por Clark M. Johnson, Brian L. Beard y Francis Albarède, 231–54. Berlin, Boston: De Gruyter, 2004. http://dx.doi.org/10.1515/9781501509360-010.

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Actas de conferencias sobre el tema "Stable isotopes geochemistry"

Zahajská, P. y J. Kvaček. "Using stable carbon isotopes in n-alkanes for palaeoreconstruction of local conditions in mangrove-like Late Cretaceous environment (Pecínov, Czechia, Central Europe)". En 29th International Meeting on Organic Geochemistry. European Association of Geoscientists & Engineers, 2019. http://dx.doi.org/10.3997/2214-4609.201902965.

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Lam, Eric, Bryan Freymuth y Carmen Berry. "Utilization of Stable Water Isotopes and Geochemistry for Detecting Seepage Pathways within North Texas Dam". En World Environmental and Water Resources Congress 2020. Reston, VA: American Society of Civil Engineers, 2020. http://dx.doi.org/10.1061/9780784482971.026.

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Salisbury, Jack, Darren Gröcke, Vincent Grossi y Ross Collin. "Biogeochemical changes in a hypersaline sabkha of the Late Permian: stable isotopes and organic geochemistry". En Goldschmidt2023. France: European Association of Geochemistry, 2023. http://dx.doi.org/10.7185/gold2023.19894.

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Calderon-Convers, Liliana, Ying Cui y Shijun Jiang. "EARLY EOCENE HYPERTHERMALS IN THE SOUTHEASTERN TETHYS: INSIGHT FROM TRACE ELEMENT GEOCHEMISTRY AND STABLE CARBON AND NITROGEN ISOTOPES". En Joint 69th Annual Southeastern / 55th Annual Northeastern GSA Section Meeting - 2020. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020se-345399.

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Quan, Hongyan, Ian Graham, Rohan Worland, Lewis Adler, Christian Dietz y Alan Greig. "Mineralisation, Alteration Assemblages, Geochemistry and Stable Isotopes of the Intermediate-Sulfidation Epithermal Kylo Deposit, Drake Goldfield, North-Eastern NSW, Australia". En The 2nd International Electronic Conference on Mineral Science. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/iecms2021-09347.

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Madayag, Emmanuel, Ian Graham, Hongyan Quan, Rohan Worland, Lewis Adler y Christian Dietz. "Mineralisation, alteration assemblages, geochemistry and stable isotopes of the low-sulfidation epithermal Strauss deposit, Drake Goldfield, north-eastern NSW, Australia". En The 2nd International Electronic Conference on Mineral Science. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/iecms2021-09350.

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Shahar, Anat. "AN EXPERIMENTAL PERSPECTIVE ON NON-TRADITIONAL STABLE ISOTOPE GEOCHEMISTRY". En GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-316957.

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Smith, Devin F., Elsa Saelens, Deborah Leselie, Marcus Liston, Sue A. Welch y Anne E. Carey. "STABLE ISOTOPE AND MAJOR ION GEOCHEMISTRY OF URBAN PRECIPITATION". En GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-306089.

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Mehay, S., N. Luu, C. Turich, M. McNall, J. Cassidy, H. Calixto Neves, T. Jacksier y A. Stankiewicz. "Shelf Life Study of Calibration Stable Isotope Hydrocarbon Mixtures for Petroleum Geochemistry Laboratories". En 29th International Meeting on Organic Geochemistry. European Association of Geoscientists & Engineers, 2019. http://dx.doi.org/10.3997/2214-4609.201902911.

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Giunta, T., M. Ader, H. Eggenkamp, M. Bonifacie y P. Agrinier. "Chlorine and Bromine Stable Isotope Compositions and Formation Water Characterisation". En EAGE Workshop on Petroleum Geochemistry in Operations and Production. Netherlands: EAGE Publications BV, 2016. http://dx.doi.org/10.3997/2214-4609.201602337.

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Informes sobre el tema "Stable isotopes geochemistry"

Kidder, J. A., M. B. McClenaghan, M I Leybourne, M. W. McCurdy, P. Pelchat, D. Layton-Matthews, C. E. Beckett-Brown y A. Voinot. Geochemical data for stream and groundwaters around the Casino Cu-Au-Mo porphyry deposit, Yukon (NTS 115 J/10 and 115 J/15). Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328862.

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This open file reports geochemical data for stream and groundwater samples collected around the Casino porphyry Cu-Au-Mo deposit, one of the largest and highest-grade deposits of its kind in Canada. The calc-alkaline porphyry is hosted in a Late Cretaceous quartz monzonite and associated breccias in the unglaciated region of west central Yukon. Water chemistry around the deposit was investigated because: (i) the deposit has not yet been disturbed by mining; (ii) the deposit was known to have metal-rich waters in local streams; and (iii) the deposit has atypically preserved ore zones. Stream water samples were collected at 22 sites and groundwater samples were collected from eight sites. Surface and groundwaters around the Casino deposit are anomalous with respect to Cd (up to 5.4 µg/L), Co (up to 64 µg/L), Cu (up to 1657 µg/L), Mo (up to 25 µg/L), As (up to 17 µg/L), Re (up to 0.7 µg/L), and Zn (up to 354 µg/L) concentrations. The stable isotopes of O and H of the groundwaters are essentially identical to the surface waters and plot close to the local and global meteoric water lines, indicating that the waters represent modern recharge, consistent with the generally low salinities of all the waters (total dissolved solids range from 98 to 1320 mg/L). Sulfur and Sr isotopes are consistent with proximal waters interacting with the Casino rocks and mineralization; a sulfide-rich bedrock sample from the deposit has delta-34S = -1.2 permille and proximal groundwaters are only slightly heavier (-0.3 to 3.1 permille). These geochemical and isotopic results indicate that surface water geochemistry is a suitable medium for mineral exploration for porphyry-style mineralization in the Yukon, and similar unglaciated regions in Canada. The atypical geochemical signature (Mo, Se, Re, As, Cu) of these types of deposits are typically reflected in the water chemistry and S isotopes provide a more local vectoring tool.

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Jacques, I. J., A. J. Anderson y S. G. Nielsen. The geochemistry of thallium and its isotopes in rare-element pegmatites. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328983.

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The Tl isotopic and trace element composition of K-feldspar, mica, pollucite and pyrite from 13 niobium-yttrium-fluorine (NYF)-type and 14 lithium-cesium-tantalum (LCT)-type rare-element pegmatites was investigated. In general, the epsilon-205Tl values for K-feldspar in NYF- and LCT-type pegmatites increases with increasing magmatic fractionation. Both NYF and LCT pegmatites display a wide range in epsilon-205Tl (-4.25 to 9.41), which complicates attempts to characterize source reservoirs. We suggest 205Tl-enrichment during pegmatite crystallization occurs as Tl partitions between the residual melt and a coexisting aqueous fluid or flux-rich silicate liquid. Preferential association of 205Tl with Cl in the immiscible aqueous fluid may influence the isotopic character of the growing pegmatite minerals. Subsolidus alteration of K-feldspar by aqueous fluids, as indicated by the redistribution of Cs in K-feldspar, resulted in epsilon-205Tl values below the crustal average (-2.0 epsilon-205Tl). Such low epsilon-205Tl values in K-feldspar is attributed to preferential removal and transport of 205Tl by Cl-bearing fluids during dissolution and reprecipitation. The combination of thallium isotope and trace element data may be used to examine late-stage processes related to rare-element mineralization in some pegmatites. High epsilon-205Tl and Ga in late-stage muscovite appears to be a favorable indicator of rare-element enrichment LCT pegmatites and may be a useful exploration vector.

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Stolper, Edward. Infrared Spectroscopy and Stable Isotope Geochemistry of Hydrous Silicate Glasses. Office of Scientific and Technical Information (OSTI), marzo de 2007. http://dx.doi.org/10.2172/900289.

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Cesar, J. R. y O. H. Ardakani. Organic geochemistry of the Montney Formation: new insights about the source of hydrocarbons, their accumulation history and post accumulation processes. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329788.

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This study consists of a non-traditional molecular and stable isotope approach to analyze organic matter (soluble bitumen and produced oil/condensate) from the Montney Formation low-permeability reservoirs, with the purpose of identifying source(s) of hydrocarbons, accumulation history and post accumulation processes. The same approach bases on the distribution of compound classes such as aromatic carotenoids, polycyclic aromatic hydrocarbons (PAHs), bicyclic alkanes, and oxygen-polar compounds. The geochemical screening has been enhanced with performing compound specific isotope analysis (CSIA) of n-alkanes and selected aromatic hydrocarbons. Widely spread PAHs, the presence of molecular indicators of euxinia, and hydrocarbon mixtures identified using CSIA profiles, are some of the key findings from this research, which will improve our understanding of the Montney petroleum system(s).

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Beckett-Brown, C. E. y J. A. Kidder. TGI Activity Report: geochemical footprint of the undisturbed Casino porphyry Cu-Mo-Ag-Au deposit, Yukon (NTS 115 J/10 and 115 J/15). Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/331831.

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A detailed geochemical sampling survey at the remote Casino porphyry Cu-Mo-Ag-Au deposit in west central Yukon is described. This new sampling follows-up on previous sampling around the deposit by the Geological Survey of Canada (GSC) in 2017. In late August-early September of 2022, a variety of sample media were collected, including bulk stream sediments, fine-grained stream sediment, pebbles, stream and groundwaters, and vegetation at 27 sites. Sampling was conducted to establish a geochemical baseline around an undisturbed, unglaciated porphyry Cu-Mo-Ag-Au deposit and to demonstrate the applicability of multi-media surficial geochemical methods for exploration in terrains with little to no bedrock outcrop. Bulk stream sediment samples will be processed to recover 0.25-2.0 mm indicator minerals, which may be subjected to further analyses (e.g., electron microprobe and LA-ICP-MS). Fine-grained sediment samples will be submitted for routine geochemical analysis to highlight the proximal geochemistry and to better understand the signal decay downstream from the deposit. Water samples will be subjected to a variety of analytical methods including trace and ultra-trace geochemistry, as well as traditional (?18O, ?2H, ?34S(SO4), and ?18O(SO4)) and non-traditional (?98Mo and ?65Cu) stable isotope analyses. The purpose of this open file is to report fieldwork activities conducted by the GSC as part of the targeted geoscience initiative (TGI-6) program. The objective of this study is to further develop research concepts conceived since 2017 and provide critical knowledge advancement for the exploration of porphyry Cu-Mo-Au deposits.

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