1. Helium isotopes at the Rainbow hydrothermal site (Mid-Atlantic Ridge, 36 degrees 14 ' N) - JEAN BAPTISTE, Philippe; FOURRE, Elise; CHARLOU, Jean-Luc; GERMAN, Christopher; RADFORD KNOERY, Joel
The He-3/He-4 ratio and helium concentration have been measured in the vent fluids and the dispersing plume of the Rainbow hydrothermal site, on the Mid-Atlantic Ridge (MAR). The He-3/He-4 ratio (7.51 R-a) and He-3 end-member concentration (25 pmol/kg) are in the range of observed values elsewhere on mid-ocean ridges, pointing to the relative homogeneity of the upper mantle with respect to helium isotope geochemistry. He-3 is linearly correlated with methane and manganese throughout the plume, with CH4/He-3 and Mn/He-3 ratios identical to those measured in the hot fluids. The bulk residence time of the plume in the rift valley estimated...

2. An assessment of sample processing methods for stable isotope analyses of coastal foodwebs - Carabel Chans, Sirka; Godínez Domínguez, Enrique; Verísimo Amor, Patricia; Fernández Rodríguez, Luis José; Freire Botana, Juan Manuel
The relative abundance of the light and heavy forms of stable isotopes of Carbon and Nitrogen is commonly used in the research of marine food webs. Dehydration of samples is needed for C and N isotopic analysis, and in those organisms with inorganic carbonate structures acidification with hydrochloric acid is also needed for sample preparation. There is not a consensus about the methodology appropriate for sample processing. In the present study, the effects of different sample processing methods in the relative abundance of stable isotopes of C and N in the different trophic compartments of a coastal food web are evaluated. The final purpose is to define...

3. Stable isotope tracing : a way forward for nanotechnology - Gulson, Brian; Wong, Herbert
Numerous publications and reports have expressed health and safety concerns about the production and use of nanoparticles, especially in areas of exposure monitoring, personal use, and environmental fate and transport. We suggest that stable isotopic tracers, which have been used widely in the earth sciences and in metabolic and other health-related studies for several decades, could be used to address many of these issues. One such example we are pursuing is the use of stable isotopes to monitor dermal absorption of zinc and titanium oxides in sunscreen preparations and other personal care products. Other potential applications of this tracing approach...

4. Carbon isotope fluctuations in Precambrian carbonate sequences of several localities in Brazil - SIAL,ALCIDES N.; FERREIRA,VALDEREZ P.; DEALMEIDA,AFONSO R.; ROMANO,ANTONIO W.; PARENTE,CLOVIS V.; DACOSTA,MARCONDES L.; SANTOS,VICTOR H.
Carbon isotope fluctuations in Precambrian sedimentary carbonates between 2.8 Ga and 0.60 Ga in Brazil are examined in this study. The carbonate facies of the BIF of the 2.8 Ga-old Carajás Formation, state of Pará in northern Brazil, has rather homogeneous delta13C (-5 o/ooPDB), compatible with carbonatization of a silicate protolith by a CO2-rich fluid from mantle degassing. The Paleoproterozoic Gandarela Formation, state of Minas Gerais, displays a narrow delta13C variation (-1.5 to +0.5 o/oo) compatible with carbon isotope signatures of carbonates deposited around 2.4 Ga worldwide. The Fecho do Funil Formation has probably recorded the Lomagundi delta13C positive anomaly...

5. Isotopes, a five year summary of U.S. distribution. - U.S. Atomic Energy Commission.
451 p. ;

6. C- and Sr-isotope stratigraphy of the São Caetano complex, Northeastern Brazil: a contribution to the study of the Meso-Neoproterozoic seawater geochemistry - Silva,Juan C.; Sial,Alcides N.; Ferreira,Valderez P.; Pimentel,Márcio M.
C-isotope and 87Sr/86Sr values for five carbonate successions from the São Caetano Complex, northeastern Brazil, were used to constrain their depositional age and to determine large variations in the C- and Sr-isotopic composition of seawater under the framework of global tectonic events. Three C-isotope stages were identified from base to top in a composed chemostratigraphic section: (1) stage in which delta13C values vary from +2 to +3.7? PDB and average 3? PDB, (2) stage with delta13C values displaying stronger oscillations (from -2? to +? PDB), and (3) stage with an isotopic plateau with values around +3.7? PDB. Constant 87Sr/86Sr values...

7. Régime et société d'après l'analyse des isotopes stables: l'exemple de la population de « Can Reinés » (Mallorca, Espagne, 600 ap. J.C.) - Garcia, Elena; Subirà, Mª Eulàlia; Richards, M. P.
Cette étude présente les résultats de l'analyse des isotopes du carbone, de l¿azote et du soufre dans le collagène osseux extrait de 39 restes humains et 20 animaux, trouvés dans un site archéologique de l'île de Mallorca, Espagne. La population étudiée est celle de « Can Reinés » (nécropole romaine, 600 ap. J.C.). Cette étude analyse, pour la période concernée, l'importance des protéines marines dans le régime alimentaire de cette population d'agriculteurs vivant près de la mer. Nous sommes également intéressés à l'influence du sexe sur l'alimentation des individus dans cette population Les résultats indiquent un régime basé principalement sur...

8. Stable isotope analysis of prehistoric human and commensal diet on Aitutaki, southern Cook Islands - Craig, Jacqueline Anne
This thesis investigates the prehistoric diet of humans and two of their key commensals on Aitutaki using stable carbon and nitrogen isotopes. This technique gives us new insight into the diet of these three groups and results are considered in the context of the development of agricultural systems on Aitutaki, as well as in light of the wider context of cultural developments and environmental change in the Cook Islands and Polynesia as a whole. Ultimately, it allows us to more fully understand the complex interactions between humans and the two largest commensals in order to evaluate the utility of these...

9. Crustal evolution in the SW part of the Baltic Shield : the Hf isotope evidence - Andersen, T; Griffin, W. L; Pearson, N. J
The results of a laser ablation microprobe–inductively coupled plasma mass spectrometry Lu–Hf isotope study of zircons in 0·93–1·67 Ga rocks from south Norway indicate that early Proterozoic protoliths of the Baltic Shield have present-day ¹⁷⁶Hf/¹⁷⁷Hf ≤ 0·28190 [εHf(t) = 5–6], whereas 1·52–1·60 Ga juvenile additions to the continental margin have ¹⁷⁶Hf/¹⁷⁷Hf = 0·2810 [εHf(t) = 12–13]. Mid- to late Proterozoic felsic igneous rocks in the region are characterized by a range of Hf isotopic compositions suggesting mixing of material derived from Palaeoproterozoic crust from the Baltic Shield and/or mid-Proterozoic juvenile crust. New mantle-derived magmas were added to the crust at...

10. Strontium and Carbon Isotope Stratigraphy of the Llandovery (Early Silurian): Implications for Tectonics and Weathering - Gouldey, Jeremy C.
A high resolution Sr isotope data set is generated for the Llandovery Series from a thick, fossiliferous drill core in Estonia. Observed ^87Sr/^86Sr values are at a minimum in the early Llandovery Rhuddanian Stage (~0.7079 to 0.7080), and then trend to more radiogenic ratios in the beginning part of the late Llandovery Telychian Stage. An ^87Sr/^86Sr high near ~0.7084 is observed in the Telychian at the top of the studied section. The range of values is in general agreement with previous sample sets of brachiopods and conodonts recovered from localities in North America and Europe that record a rising trend...

11. Comparison of lead isotopes with source apportionment models, including SOM, for air particulates - Gulson, Brian; Korsch, Michael; Dickson, Bruce; Cohen, David; Mizon, Karen; Davis, J. Michael
We have measured high precision lead isotopes in PM₂.₅ particulates from a highly-trafficked site (Mascot) and rural site (Richmond) in the Sydney Basin, New South Wales, Australia to compare with isotopic data from total suspended particulates (TSP) from other sites in the Sydney Basin and evaluate relationships with source fingerprints obtained from multi-element PM₂.₅ data. The isotopic data for the period 1998 to 2004 show seasonal peaks and troughs that are more pronounced in the rural site for the PM₂.₅ samples but are consistent with the TSP. The Self Organising Map (SOM) method has been applied to the multi-element PM₂.₅...

12. Tracing Cu and Fe from source to porphyry : in situ determination of Cu and Fe isotope ratios in sulfides from the Grasberg Cu-Au deposit - Graham, S; Pearson, N; Jackson, S; Griffin, W; O'Reilly, S. Y
ℇ⁶⁵Cu ([⁶⁵Cu/⁶³Cusample/⁶⁵Cu/⁶³CuNIST₋₉₇₆ -1]*10,000) in chalcopyrite from the 3 three igneous intrusions that make up the Grasberg Igneous Complex (GIC) and associated skarn deposits range from 0.2 to 13.4. Chalcopyrite grains from each intrusion have a specific range of ℇ⁶⁵Cu that is isotopically heavier in each successive intrusion. These variations may be interpreted in two ways: (1) isotope fractionation during distillation of Cu from the underlying source and establishment of hydrothermal cells associated with each intrusion; (2) isotope fractionation as the ore ore-bearing fluid moved outward from a central core. Within each sample, the smaller disseminated chalcopyrite grains yield consistently lower...

13. Integração de dados mineralógicos, isótopos estáveis (O, H) e porosidade de rochas (14C-PMMA) no reconhecimento da evolução da alteração no sistema hidrotermal de Lavras do Sul/RS, Brasil - Bongiolo, Everton Marques
O distrito mineiro de Lavras do Sul compreende prospectos contendo Au-Cu (±Pb, Zn, Ag) em uma seqüência plutono-vulcânica neoproterozóica no Sul do Brasil. As mineralizações ocorrem em veios e brechas de quartzo com direção preferencial N40°W a E-W e em halos hidrotermais nas encaixantes. Os principais minerais de alteração associados às mineralizações filonianas nos granitóides e nas rochas vulcanogênicas compreendem sericita e clorita, respectivamente. Estudos de campo, petrografia (ótica e MEV), difratometria de raios X, decomposição de difratogramas e química mineral das zonas de alteração mineralizadas mostram que as sericitas associadas à alteração fílica compreendem: (i) fengita, ilita e interestratificados...

14. Determination of Cd, Pb, Zn and Cu in Sediment Compartments by Sequential Extraction and Isotope Dilution Inductively Coupled Plasma Mass Spectrometry (ID-ICP-MS) - Gardolinski,Paulo C. F. C.; Packer,Ana P.; Almeida,Celso R. de; Giné,M. Fernanda
Trace concentrations of Cd, Cu, Pb and Zn in four different sediment fractions extracted in sequence were determined by isotope dilution inductively coupled mass spectrometry (IDICPMS). The metals from each fraction were extracted following the sequential extraction procedure recommended by the Bureau Commun de Référence (BCR) of the Commission of the European Communities. As an alternative to external calibration, the elements were quantified by spiking the extracted solutions with 112Cd, 63Cu, 208Pb and 66Zn and application of isotope dilution. The proposed approach was applied to a sample collected from a lake and two standard reference materials, NIST2704 river sediment from...

15. Stable isotope characterization of the thermal profile and subsurface biological activity during oxidation of the Great Australia deposit, Cloncurry, Queensland, Australia - Melchiorre, Erik B.; DePauw University; Williams, Peter A.
The application of stable isotope thermometry and phase relations was used to examine the thermal evolution of oxidation and secondary mineralization at the Great Australia Cu-Au-Co deposit, Cloncurry, Queensland, Australia. Results show that early secondary mineralization consisted of djurleite crystallization at temperatures <93°C, followed by calcite mineralization at 66° to 75°C. The secondary mineralization paragenesis continued with azurite that formed at about 51°C, followed by malachite crystallization at 41° to 38°C, and malachite after azurite at 34°C. The final stage of secondary mineralization consists of calcite that formed at 25° to 30°C, followed by goethite. The general trend observed is...

16. Stable isotope characterization of the thermal profile and subsurface biological activity during oxidation of the Great Australia deposit, Cloncurry, Queensland, Australia - Melchiorre, Erik B.; DePauw University; Williams, Peter A.
The application of stable isotope thermometry and phase relations was used to examine the thermal evolution of oxidation and secondary mineralization at the Great Australia Cu-Au-Co deposit, Cloncurry, Queensland, Australia. Results show that early secondary mineralization consisted of djurleite crystallization at temperatures <93°C, followed by calcite mineralization at 66° to 75°C. The secondary mineralization paragenesis continued with azurite that formed at about 51°C, followed by malachite crystallization at 41° to 38°C, and malachite after azurite at 34°C. The final stage of secondary mineralization consists of calcite that formed at 25° to 30°C, followed by goethite. The general trend observed is...

17. Safe handling of radioactive isotopes [prepared by the Subcommittee on the Handling of Radioactive Isotopes and Fission Products of the National Committee on Radiation Protection] - United States. National Committee on Radiation Protection and Measurements.
vi, 30 p.

18. Boron isotope dilution in cellular fractions of coffee leaves Evaluated by Inductively Coupled Plasma Mass Spectrometry with direct injection nebulization (DIN-ICP-MS) - Bellato,Ana Cláudia S.; Menegário,Amauri A.; Giné,Maria Fernanda
Enriched 10B (94.14 atom %) was supplied to coffee plantlets for three months. Then boron isotope ratios were determined in the leaf cell compartments, cell wall, nuclei and chloroplast, after a sub-cellular fractionation procedure. The isotopic measurements were performed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) provided with a direct injection nebulizer (DIN), introducing a sample volume of 50 muL. Isotopic ratios from 1.002 to 1.326 were determined with precision characterized by RSD lower than 1.5% for the enriched cell fractions with B concentrations ranging from 3.3 to 10.8 mug g-1. The detection limit (3sigma) was 0.5 ng B mL-1....

19. Dinâmica da vegetação e inferências climáticas no Quaternário Tardio na região da Ilha de Marajó (PA), empregando os isótopos do carbono (12C, 13C, 14C) da matéria orgânica de solos e sedimentos - Claudia Moré de Lima
Considerada a maior ilha flúvio-marítima do mundo, com aproximadamente 48.000 km2, a Ilha de Marajó situa-se na zona equatorial brasileira, no litoral do Estado do Pará. Apresenta dois domínios distintos relacionados a geologia e vegetação. No setor oeste dominam solos desenvolvidos sobre os sedimentos Pós Barreiras (plio-pleistocênicos) recobertos pela Floresta Amazônica, enquanto no setor leste dominam sedimentos holocênicos derivados de ambiente fluvial/estuarino atualmente desativado. Neste setor encontram-se os extensos campos naturais marajoaras. O objetivo deste trabalho consistiu em aplicar os isótopos de carbono (12C, 13C e 14C) da matéria orgânica de solos e sedimentos com o intuito de avaliar possíveis...

20. Calculation of isotope shifts and relativistic shifts in CI, CII, CIII, and CIV - Berengut, Julian Carlo, Physics, Faculty of Science, UNSW; Flambaum, Victor, Physics, Faculty of Science, UNSW; Kozlov, M.G, Petersburg Nuclear Physics Institute

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