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The solar system is assumed to be uniform on a large scale in terms of the isotope composition of refractory elements. Here we show that the titanium (Ti) isotope compositions of carbonaceous chondrites differ from those of ordinary chondrites, eucrites, mesosiderites, ureilites, the Earth, Moon, and Mars, all of which are indistinguishable. Leachates and mineral separates demonstrate that this feature is homogeneously distributed within a range of phases in the carbonaceous chondrites Allende and Renazzo. The data therefore indicate that the solar nebula that fed planetesimals between ∼ 1 AU and ∼ 2.4 AU, e.g. Earth, Moon, Mars and the parent bodies of ordinary chondrites, eucrites, ureilites, and mesosiderites, was homogeneous for Ti (and Sr, Ba, Nd, Sm) isotopes. In contrast, carbonaceous chondrites, which probably formed beyond ∼ 2.7 AU appear to have acquired a distinct mix of primitive components, which is consistent with their lack of depletion in volatile elements and late formation. © 2007 Elsevier B.V. All rights reserved.

Forgeries of ancient gold objects are prevalent in almost every collection and some public exhibitions in the past have been exposed as containing forgeries to an embarrassing extent. This situation comes from the fact that it is sometimes impossible to unequivocally recognize forgeries based on their patina or manufacturing and decoration characteristics. We demonstrate that for 13 ancient gold objects the time of their last melting process can be estimated using the U,Th- 4 He dating technique. The extremely small quantities of radiogenic 4 He found, due to the young age and small sample size, require the use of a specially designed ultrasensitive mass spectrometer. We show that the proposed method is a powerful, and the only, quantitative tool in archaeometry for discriminating between fake and genuine ancient gold objects.

We applied three techniques (DF-ICP-MS, PERALS and alpha-spectrometry) for the determination of minor actinides at environmental levels. For each method the limit of detection and the resolution were estimated in order to study the content and isotopic composition of the actinides. Two international reference materials, IAEA-135 (Irish Sea Sediment) and IAEA-300 (Baltic Sea sediment) were analyzed for activity concentrations of 238Pu, 239Pu, 240Pu, 241Pu and 241Am. The sensitivities of the three determination techniques were compared.

The aim of this study was to assess the suitability of Norway spruces (Picea abies L. Karst.) as an environmental archive for sulphur. For this purpose spruce trees were sampled in two distinct regions of Switzerland: the Alps and the Swiss Plateau, which differ significantly with respect to S immission. Wood samples were measured using two methods: LASER Ablation high resolution inductively coupled plasma mass spectrometry (LA-HR-ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES) after acid digestion. Independently corroborated by previous measurements of sulphur in peat bogs, the rise and fall of sulphur dioxide pollution in Switzerland appears to be reflected in spruce wood sulphur content. While the wood sulphur content profile of trees sampled in the Alps is relatively flat, the profiles of trees located on the Swiss Plateau display a characteristic sulphur peak. This corresponds to air pollution data in the different regions and indicates that the trees reacted on the changing S supply and recorded a pollution signal in the wood.

Methods were developed for detailed dendrochemical studies of low sulphur contents in Norway spruce (Picea abies L. Karst.). This tree species is the dominant conifer species in Northern and Central Europe and therefore predestined for a possible use as an environmental archive. Two independent digestion procedures were investigated with respect to their suitability for element determination and optimised for analysis of the low sulphur content in wood. A modified oxygen bomb combustion procedure and a microwave acid digestion procedure were evaluated with the goal to obtain sufficient detection limits in order to access low concentrated non-metals with an appropriate time resolution. Method development included evaluation of strategies preventing losses of volatile sulphur species. Digestion efficiency was demonstrated by recovery rates for various certified plant standard reference materials (NIST 1572, NIST 1547, RM 8436, BCR 101, NIST 1515, RM 8436, NIST 1573, NIST 1575) as well as self prepared standards with defined low sulphur content of 20 to 200 mg kg−1, which are typical for Norway spruce wood samples. Ultra sonic nebulisation (USN) was evaluated with respect to signal enhancement for sample introduction to inductively coupled plasma optical emission spectrometry (ICP-OES). The optimised procedure was applied to Norway spruce drill cores from locations with different environmental conditions in Switzerland, in order to investigate the anthropogenic impact of sulphur and the suitability of Norway spruce as an environmental archive for sulphur.

Profiles of the major sulfur functional groups in mature Norway spruce wood tissue have been established for the first time. The big challenge was the development of a method suitable for sulfur speciation in samples with very low sulfur content (

Element-specific time-resolved in situ corrosion susceptibility of the Zr 58.5 Cu 15.6 Ni 12.8 Al 10.3 Nb 2.8 bulk metallic glass was studied using a novel microcapillary flow injection inductively coupled plasma mass spectrometry (microcapillary FI-ICP-MS) technique. In comparison to the time consuming and sample demanding static immersion tests, the new set-up allows element-specific in situ investigations of corrosion dissolution rates with a high time resolution. Moreover, online monitoring of corrosion processes can be performed at a single sample spot. Time-resolved profiles of element release from Zr 58.5 Cu 15.6 Ni 12.8 Al 10.3 Nb 2.8 were investigated in 1 M HCl and 1 M HNO 3 under the open circuit potential conditions. Preferential dissolution of Cu and Al from the Zr-bulk metallic glass was determined. Moreover, X-ray photoelectron spectroscopy (XPS) was employed to characterize the composition of the oxide film before and after the immersion in acidic corrosive medium. Based on microcapillary FI-ICP-MS and XPS results the mechanisms for simultaneous Al and Cu depletion and Zr content enrichment in the oxide film were proposed.

We report here the petrography. mineralogy. and geochemistry Of lunar meteorite Sayh al Uhaymir 300 (SaU 300). SaU 300 is dominated by it fine-grained crystalline matrix surrounding mineral fragments (plagioclase, pyroxene, olivine, and ilmenite) and lithic clasts (mainly feldspathic to noritic). Mare basalt and KREEPy rocks are absent. Glass melt veins and impact melts are present. indicating that the rock has been subjected to a second impact event. FeNi metal and troilite grains were observed in the matrix. Major element concentrations of SaU 300 (Al(2)O(3) 21.6 wt% and FeO S. 16 wt%) are very similar to those of two basalt-bearing feldspathic rei, regolith breccias: Calcalong Creek and Yamato (Y-) 983885. However. the rare earth element (REE) abundances and pattern of SaU 300 resemble the patterns of feldspathic highlands meteorites (e.g., Queen Alexandra Range (QUE) 93069 and Dar al Gani (DaG) 400), and the average lunar highlands crust. It has a relatively LREE-enriched (7 to 10 x CI) pattern with a positive Eu anomaly (similar to 11 x CI). Values of Fe/Mn ratios of olivine. pyroxene, and the bulk sample are essentially consistent With l lunar origin. SaU 300 also contains high siderophile abundances with a chondritic Ni/Ir ratio. SaU 300 has experienced moderate terrestrial weathering as its bulk Sr concentration is elevated compared to Other lunar meteorites, and Apollo and Luna samples. Mineral chemistry and trace clement abundances of SaU 300 fall within the ranges of lunar feldspathic meteorites and FAN rocks. SaU 300 is a feldspathic impact-melt breccia predominantly composed of feldspathic highlands rocks with a small amount of mafic component. With a bulk Mg# of 0.67, it is the most mafic of the Feldspathic meteorites and represents a lunar surface composition distinct from any other known lunar meteorites. Oil the basis of its low Th concentration (0.46 ppm) and its lack of KREEPy and mare basaltic components, the source region of SaU 300 could have been within a highland terrain, a great distance from the Imbrium impact basin, probably on the far side of the Moon.

Archaeological fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil. The fluorine ion replaces the hydroxyl group in the mineral phase of the bone, forming chemically more stable fluorapatite. In cortical parts of the long bone diaphysis a fluorine concentration profile can be observed, which decreases from the outer surface and the marrow cavity towards the inner parts of the bone matrix. Geological time spans are needed for this process to reach equilibrium and for the distribution to become uniform. As the shape of the profile, which can be described by a diffusion model, contains information on the exposure duration of the fossil object, several attempts to use fluorine profiling as a dating method have been undertaken. The distribution of fluorine in an archaeological sample however is strongly influenced by environmentally induced processes of bone diagenesis, i.e. alteration in the structure and composition of the mineral phase and degradation of organic components that may make the time information indistinct. The primary chemical composition of bones can thus be obscured by diagenesis within tens, hundreds or thousands of years. This depends more on the diagenetic environment than on the geological age. To observe the impact of environmental influence on the profile shape, samples from several burial sites featuring various soil conditions have been analyzed for their fluorine distribution and preservation state. This paper provides an overview on the restrictions that have to be considered when attempts are undertaken to relate a fluorine diffusion pattern to the archaeological age of a bone specimen.

A method has been developed for the precise and reproducible measurement of Ti isotopes in natural materials using high resolution MC-ICPMS. Instrumental mass fractionation is internally corrected using 49Ti/47Ti. Replicate measurements of synthetic standard solutions, terrestrial rocks, and the carbonaceous chondrite Allende yield a long-term reproducibility (2σ) of 0.28ε, 0.34ε, and 0.28ε for 50Ti/47Ti, 48Ti/47Ti, and 46Ti/47Ti, respectively. Isobaric interferences from 46,48Ca+, 50V+, 50Cr+, and doubly charged Zr can be corrected for reliably in separated Ti solutions with Ca/Ti < 5, V/Ti < 0.3, Cr/Ti < 0.2, and Zr/Ti < 1, respectively. Such elemental ratios are achieved easily in most samples using the anion-exchange procedure presented. Single and double charged polyatomic ions can either be resolved, e.g., 14N36Ar+, or do not compromise the measurements. The method has been successfully applied to terrestrial rocks, meteorites, and various mineral separates. Terrestrial samples and standards agree within analytical uncertainties but are consistently different from the recommended values of Niederer et al. [F.R. Niederer, D.A. Papanastassiou, G.J. Wasserburg, Geochim. Cosmochim. Acta 45 (1981) 1017] with the largest effect on 50Ti/47Ti. The new results provide evidence that the recommended terrestrial 50Ti/47Ti is not well constrained; our data are higher by ∼13ε than the recommended value. Better agreement is found with the values recommended by Heydegger et al. [H.R. Heydegger, J.J. Foster, W. Compston, Earth Planet. Sci. Lett. 58 (1982) 406]. Our best estimate for the isotopic composition of terrestrial Ti (relative to 49Ti/47Ti = 0.749766) is: 50Ti/47Ti = 0.73010, 48Ti/47Ti = 10.06884, and 46Ti/47Ti = 1.09325. This corresponds to an atomic weight of 47.877, significantly different from the value of 47.867 recommended by IUPAC. A 50Ti/47Ti anomaly for bulk Allende of 3.37 ± 0.51ε is found, while for 48Ti/47Ti and 46Ti/47Ti the data are identical to the terrestrial value within the uncertainties. This is consistent with other recently reported differences between the bulk Earth and chondrites in neutron-rich nuclides. © 2006 Elsevier B.V. All rights reserved.

The iron meteorite Shisr 043 is a single mass of 8267 g found in the south Oman desert 42 km NE of the Shisr village. It is the first iron identified among the >1400 individual meteorites reported from Oman. The meteorite is a slightly elongated mass showing only minor rusting, a partially smooth and partially rough surface with octahedral cleavage, and a partially preserved metallic fusion crust typically 0.75 mm thick. The undeformed Widmanstatten pattern with a mean kamacite bandwidth of 1.0 0.1 mm (n = 97) indicates structural classification as a medium octahedrite. From the bulk composition, Ni = 8.06 wt%, Ga = 18.8 ppm, Ge = 37.25 ppm, and Ir = 3.92 ppm, the meteorite is classified as IIIAB, the most common group of iron meteorites. The cosmic-ray exposure (CRE) age based on 3He, 21Ne, 38Ar concentrations and 10Be-21Ne, 26Al-21Ne, and 36Cl-36Ar ratios is 290 ± 20 Ma. This age falls within the range observed for type IIIAB iron meteorites, but does not coincide with the main cluster. The cosmogenic noble gas and radionuclide data indicate that Shisr 043 had a relatively small preatmospheric mass. The low degree of weathering is consistent with a young terrestrial age of

The effects of uranium and its progeny radium are known to be harmful and their measurements in drinking water are necessary for careful monitoring. Fast and accurate methods for determination of uranium and radium in water samples with various salinity and activities concentrations have been developed. High Resolution Inductively Coupled Plasma Mass Spectrometry is used for direct measurement of uranium. Calibration is performed with 238U standards and 209Bi is used as internal standard to correct the matrix effects and plasma instability. The radium is determined by photon electron rejected alpha liquid spectrometry after a chemical separation procedure that includes co-precipitation of radium with barium sulphate, transformation of the sulphate to carbonate and extraction of radium in the scintillation cocktail. The minimal detectable activities of 3.5×10−8 Bq kg−1 for uranium and 2.3×10−4 Bq kg−1 for radium are obtained.

SummaryA fast and simple method for the determination of237Np in soil is presented. The borate fusion decreases the sample pre-treatment time and a TEVA extraction chromatography separates neptunium from uranium and the interfering matrix components. A comparison of the sensitivities of alpha spectrometry and sector field ICP-MS for determination of237Np is presented.

Summary The purpose of this study was to develop an optimised sample preparation method for the determination of Pu, Am, and Cm in environmental samples, soils, and sediments, and to compare the sensitivities of DF-ICP-MS, alpha spectrometry, and liquid scintillation alpha spectrometry. Borate fusion was used for sample material digestion. Two methods based on TOPO liquid–liquid extraction and combination of TEVA and TRU extraction chromatography showed highest yields of 92.7% for Pu, 86.8% for Am, and 87.6% for Cm. The detection limits were between 0.014–0.034 Bq/kg for 239Pu, 0.014–0.093 Bq/kg for 240Pu, and 0.011–1.20 Bq/kg for 241Am. Analytical results for 238Pu, 239Pu, 240Pu, 241Pu and 241Am and their isotope ratios in certified reference materials (IAEA-135 and IAEA-300) indicated very good accuracy of the methods proposed.

Fossil fragments of bone and teeth that are exposed to a humid environment take up fluorine from the surrounding soil and accumulate it in their mineral phase. In cortical parts of long bone diaphysis a fluorine concentration profile can be observed, which carries information on the exposure duration of the buried object in its shape. The distribution of fluorine in a sample however is strongly influenced by environmentally induced processes of bone diagenesis, i.e. alteration in the structure and composition of bone mineral and degradation of the organic components that may make the time information indistinct. PIGE (Proton Induced Gamma-ray Emission) is a precise and fast analytical technique to determine the quantitative fluorine content and its distribution in cross sections of bone and tooth specimen non-destructively. The simultaneous detection of Ca by PIXE (Proton Induced X-ray Emission) provides additional information on the sample topography. Cracks, alteration haloes and the porosity, which is typical for human bone samples, are parameters which have direct influence on the fluorine uptake and transport during burial. This contribution outlines the combined approach of using PIGE and PIXE measurement to understand some aspects of the complex environmental impact that impedes exposure age dating by fluorine diffusion profiling.

Proton-induced production cross sections of 129I from Te and Ba are presented. Earlier assumptions that Te is the most important target element in meteoroids are confirmed. Based on this data set and the experimental production rates of 129I from thick-target experiments, the production of 129I in stony meteoroids is modeled using a GCR flux density of 4.06 cm^(-2) s^(-1). The results of this modeling must be considered preliminary because the contribution from neutron capture on 128Te needs further investigation. We obtained modeled production rates that agree with experimental results for samples from two medium-sized meteorites (Abee and Knyahinya). However, we find that this model does not describe 41Ca in lunar rocks well and seems to overestimate 129I production in larger bodies, such as Allende. We present elemental production rates from Te and Ba based on our modeling as well as for a model that describes neutron capture products. For 129I analysis of Knyahinya, a novel method to separate Te and analysis using ICP-MS was used, enabling the use of experimental elemental concentrations obtained from the same meteorite to calculate 129I production.

The enrichment of fluorine on the surface of Antarctic meteorites is investigated by applying the nuclear reactions 19 F(p, a ) 16 O or 19 F(p, p¢ ) 19 F with the proton induced gamma emission (PIGE) technique, a class of nuclear reaction analysis (NRA). Results for the Antarctic meteorites ALHA77294, TIL 82409, LEW 86015, ALHA77003, and ALH 83108 are presented. Possible sources of terrestrial F are: volcanic exhalation, tephra layers (volcanic glass), continental soil dust, or sea spray. Material from blue-ice dust-band samples also shows concentrations of F that are significantly higher than the bulk concentrations of meteorites. Finally, a quick investigation for Antarctic meteorites by external PIGE is proposed, leading to a F-contamination index that supplements the qualitative ABC-weathering index.

The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories - virtually all those performing geochemical boron isotope analyses in the world -which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution. L'Istituto di Geoscienze e Georisorse (IGG), pour le compte et avec le soutien de l'Agence Internationale de l'Energie Atomique (AIEA), a prepare huit materiaux geologiques (trois eaux naturelles et cinq roches et mineraux) destines a la conduite d'une comparaison en aveugle des mesures de composition isotopique et de concentration du bore entre differents laboratoires. Vingt-sept laboratoires -pratiquement tous ceux qui travaillent sur les isotopes du bore en geochimie - ont accepte de participer a cette intercomparaison, mais quinze seulement ont finalement envoye leurs donnees de composition isotopique et/ou de concentration du bore. Les resultats demontrent que la precision des valeurs indiquee par les laboratoires reflete mal la reproductibilite entre laboratoires des mesures de composition isotopique comme de concentration du bore. Les raisons de ces discordances peuvent comprendre l'existence de fractionnements isotopiques dus aux matrices chimiques des materiaux, un deplacement relatif du zero de l'echelle de δ11B, ainsi que le manque de materiaux bien caracterises pour calibrer les mesures de concentration du bore. Les materiaux utilises pour l'intercomparaison des mesures sont maintenant a disposition a l'AIEA (materiaux solides) et l'IGG (eaux) pour etre distribues.

Cysteine synthesis from sulfide andO-acetyl-l-serine (OAS) is a reaction interconnecting sulfate, nitrogen, and carbon assimilation. UsingLemna minor, we analyzed the effects of omission of CO2 from the atmosphere and simultaneous application of alternative carbon sources on adenosine 5′-phosphosulfate reductase (APR) and nitrate reductase (NR), the key enzymes of sulfate and nitrate assimilation, respectively. Incubation in air without CO2 led to severe decrease in APR and NR activities and mRNA levels, but ribulose-1,5-bisphosphate carboxylase/oxygenase was not considerably affected. Simultaneous addition of sucrose (Suc) prevented the reduction in enzyme activities, but not in mRNA levels. OAS, a known regulator of sulfate assimilation, could also attenuate the effect of missing CO2 on APR, but did not affect NR. When the plants were subjected to normal air after a 24-h pretreatment in air without CO2, APR and NR activities and mRNA levels recovered within the next 24 h. The addition of Suc and glucose in air without CO2 also recovered both enzyme activities, with OAS again influenced only APR.35SO4 2− feeding showed that treatment in air without CO2 severely inhibited sulfate uptake and the flux through sulfate assimilation. After a resupply of normal air or the addition of Suc, incorporation of 35S into proteins and glutathione greatly increased. OAS treatment resulted in high labeling of cysteine; the incorporation of 35S in proteins and glutathione was much less increased compared with treatment with normal air or Suc. These results corroborate the tight interconnection of sulfate, nitrate, and carbon assimilation.

SummaryThe separation of plutonium from marine sediments (IAEA-135 reference material) by solvent extraction and determination with Photon Electron Rejecting Liquid Alpha Spectrometry (PERALS®) has been performed. Two extraction schemes, TOANO3and HDEHP, were compared for the separation of plutonium, uranium, thorium and americium from the matrix components. The TOANO3separation method showed plutonium recovery of 85% with an accuracy of ±20%, while for the HDEHP separation the plutonium recovery was only 9.3%. Minimum detectable activities of plutonium for a counting time of 120000 seconds for 0.25 g sample material were 0.18 Bq/kg for TOANO3and 1.62 Bq/kg for HDEHP separation methods, respectively.

The separation of uranium and thorium from complex matrixes such as marine sediments using solvent extraction and determination by means of Photon-Electron Rejecting Liquid Alpha Spectrometry (PERALS®) has successfully been performed. Two extraction schemes, using TOPO and HDEHP, respectively, were compared for the separation of uranium and thorium from the matrix components. The results show recoveries between 73 and 92% for 234U, 238U, 232Th, 230Th and 228Th with an accuracy of the methods ±12%. Minimum detectable activities for counting time up to 500000 seconds for 0.5 g sample material were between 0.34-1.15 Bq/kg for uranium and 0.31-1.66 Bq/kg for thorium.

Isotopic compositions and abundances of boron were measured in sixteen chondrules from seven chondrites by ion microprobe mass spectrometry. The chondrules are of the porphyritic, barred, and radial type and host meteorites include carbonaceous, ordinary, and enstatite chondrites. Boron abundances are generally low with average boron concentrations of between 80 and 500 ppb. These abundances are lower than those of bulk chondrites (0.35 to 1.2 ppm; Zhai et al., 1996), confirming earlier suggestions that boron is mostly contained in the matrix. No significant variation in the 11B/10B ratio is observed among these chondrules, outside our experimental error limits of several permil, and B-isotopic compositions agree with those reported for bulk chondrites. The lack of a significant isotope fractionation between chondrules and matrix implies that the low boron abundances are not the result of a Rayleigh fractionation during chondrule formation. Isotopic heterogeneities within individual chondrules are constrained to be ± 20%0 at 95% confidence level at a spatial scale of 20-30 μ m, significantly lower than the value of about ± 40%0 previously reported for chondrules from carbonaceous and ordinary chondrites (Chaussidon and Robert, 1995, 1998). The observed B-isotopic homogeneity does not conflict with the presence of decay products from extinct 10Be, with (10Be/9Be)0≅ 10-3, as was inferred for calcium-aluminum-rich inclusions. Extinct 10Be in chondrules would shift the abundance ratio 11B/10B at best by several permil because of their commonly observed low Be/B ratios (2). The results show that potential B-isotopic heterogeneities in the solar nebula due to the presence of components with different B-isotopic signatures, such as boron produced by high-energy galactic cosmic rays (11B/10B ≅ 2.5), or by the hypothetical low-energy particle irradiation (11B/10B ≅ 3.5-11) or boron from type II supernovae (11B/10B » 1), did not survive the chondrule formation processes to a measurable extent.

Following the discovery of an apparent precompaction irradiation of a chondrule, we studied the isotopic abundances of noble gases He, Ne, and Ar in separated chondrule and matrix samples of eight ordinary chondrites. The chondrules show systematically larger concentrations of cosmogenic He, Ne, and with one exception, Ar when compared to the corresponding matrix samples. Different exposure times were calculated based on production rates, which take into account the abundances of relevant target elements in each chondrule and matrix sample. The 81Kr-Kr method was used for samples of Bjurbole to verify that different exposure times are not due to either a bias in production rates or to systematic losses of noble gases from matrix. This method self-corrects for variable shielding, is independent of calculated production rates, and insensitive to gas loss. The results show that differences in exposure ages are due to different precompaction exposures of chondrules, or components thereof, before final assembly of the meteorite. For the Sena chondrite we studied various chondrule and matrix constituents. For this meteorite we found chondrule preexposures relative to the matrix material, with magnetic chondrules showing the largest effect.

Sediment cores were collected at the MOLAR (MOuntain LAke Research) site Jorisee. The goal of the analysis was to date the sediment cores in order to correlate actual input conditions of nutrients and pollutants at this high-alpine, remote site, to historical situations. The sediment cores were dated by determining gamma rays of Pb-210 and Cs-137. The calculated sedimentation rate is 0.1 cm/year. Leaching techniques were used to investigate redox sensitive species. The results give evidence for post depositional recycling in case of Fe and Mn. In contrast, the heavy metals Pb, Zn, Cr and Ni are not affected by existing redox gradients. Sediment samples were leached with diluted nitric acid to determine anthropogenic input of Pb, Zn, Cr and Ni. Concentrations of these heavy metals reflect changes in the input conditions since the beginning of industrialization, which is the examined time period.

The fossil H chondrite Brunflo, found in a slab of Ordovician limestone from central Sweden, is pervasively altered to an assemblage dominated by calcite and barite. The meteorite is surrounded by a 15-20 cm wide zone of lighter colors than the unaffected limestone due to dissolution of hematite. Here we present detailed geochemical analyses of two meteorite samples, 14 limestone samples at distances from 0 to 29 cm along two profiles from the meteorite, and a reference sample of Brunflo limestone. Element concentrations in Brunflo and surrounding bleached limestone have been strongly disturbed . during two stages of alteration early oxygenated and deep burial . In the meteorite, the Ni rCo ratio has changed from an initial value of 20 to 0.8 and redox sensitive elements like V, As, Mo, Re and U are strongly enriched. The sulfur isotope 34 . composition of barite from Brunflo d S sq 35‰ indicates initial loss of meteoritic sulfide, followed by later accumulation of sea water sulfate as barite. During deep burial under more reducing conditions, reduction processes supported by an externally derived reductant possibly derived from alum shale underlying the limestone, were largely responsible for the observed redox phenomena. In spite of massive redistribution of many elements, concentrations of Pt, Ir and Au remain at chondritic levels. The geochemistry and mineralogy of alteration determined for Brunflo are similar to .

We studied the cosmic-ray records of the H6 chondrite ALH76008 in a bulk sample, in a chondrule fragment, and in matrix material. The matrix was separated into olivine/pyroxene, plagioclase, and metal concentrates. For all samples He, Ne, and Ar isotopic measurements were performed. The cosmic-ray exposure age of the bulk chondrite is 1.72 ± 0.11 Ma, whereas the 3He, 21Ne, and 38Ar ages of the chondrule exceed those of bulk material by 31%, 67%, and 55%, respectively. The radiation environment in the early solar system is ill defined, but for current production rates this translates into a precompaction exposure time of 0.90 Ma. Furthermore, the plagioclase (mainly anorthite) concentrate, representing a few percent of the total meteorite, contains solar-type noble gases that reveal differential irradiation of ALH76008 components. We observe a trapped ratio 20Ne/22Ne = 12.3 ± 0.3, a value that is between those of solar wind and solar energetic particles. This is the first clear identification of differential irradiation conditions between a chondrule and the bulk chondrite; the short exposure age may favor the resolution of differential exposure histories.

Noble gas isotopic abundances of ten lodranites (EET84302, FRO90011, Gibson, LEW86220, LEW88280, Lodran, MAC88177, QUE93148, Y74357, Y791491) and four acapulcoites (Acapulco, ALH81187, ALH81261, ALH84190), as well as major, minor, and trace element compositions of six lodranites (EET84302, Gibson, LEW88280, Lodran, MAC88177, Y791491), are reported. Because existing empirical production rate models for cosmic-ray-produced nuclides in achondrites could not account for the effects of bulk chemical composition and for the unique shielding conditions in lodranites and acapulcoites, we modeled the production rates of cosmogenic nuclides in lodranites and acapulcoites by galactic and solar cosmic rays using a purely physical model. All lodranites and acapulcoites are relatively small meteorites having preatmospheric radii ≤ 200 mm, one-half of them even ≤75 mm. Evidence was found for solar-cosmic ray produced nuclides in the acapulcoites ALH77081, ALH81187, ALH81261, and ALH84190. The derived cosmic-ray exposure ages of all lodranites (with the exception of QUE93148 with 15 Ma) and all acapulcoites cluster around 6 Ma, suggesting, supported by the similar abundances of cosmogenic nuclides, similar shielding conditions, and similar chemical compositions, that they all originate from one ejection event from the same parent body. Within error limits identical abundances of cosmogenic nuclides, identical shielding conditions, and identical cosmic-ray exposure ages support pairing between ALH77081 and ALH81261, and ALH81187 and ALH84190.

The enrichment of F on Antarctic meteorites is the result of their exposure to the atmosphere, and its measurement allows a subdivision of the terrestrial age into a duration of exposure on the ice and the time a meteorite was enclosed by the ice. In many cases, the periods of surface exposure are only small fractions of the terrestrial ages of meteorites collected in Antarctica. The enrichment of F on the surfaces of Antarctic achondrites was investigated by means of nuclear reaction analysis (NRA): scanning proton beams with an energy of 2.7 and 3.4 MeV were used to induce the reactions 19F(p, alpha gamma)16O and 19F(p,p gamma)19F, respectively. Gamma signals proportional to the F content were measured. The following Antarctic achondrites were investigated: Martian meteorite ALH 84001; diogenite ALHA77256; the eucrites ALHA81011 and ALHA78132; and in addition, the H5 chondrite ALHA79025. For ALH 84001, our data indicate a period of exposure on the ice of500 years. Thus, this specimen was enclosed in the ice95% of its terrestrial age of 13 000 years.

— We report the elemental and isotopic composition of the noble gases as well as the chemical abundances in pyroxene, maskelynite/mesostasis glass, and bulk material of Shergotty and of bulk samples from Chassigny and Yamato 793605. The 40K-40Ar isochron for the Shergotty minerals yields a gas retention age of 196 Ma, which is, within errors, in agreement with previously determined Rb-Sr internal isochron ages. Argon that was trapped at this time has a 40Ar/36Ar ratio of 1100. For Chassigny and Y-793605, we obtain trapped 40Ar/36Ar ratios of 1380 and 950, respectively. Using these results and literature data, we show that the three shergottites, Shergotty, Zagami, and QUE 94001; the lherzolites ALH 77005, LEW 88516, and Y-793605; as well as Chassigny and ALH 84001 contain a mixture of Martian mantle and atmospheric Ar; whereas, the trapped 40Ar/36Ar ratio of the nakhlites, Nakhla, Lafayette, and Governador Valadares cannot be determined with the present data. We show that Martian atmospheric trapped Ar in Martian meteorites is correlated with the shock pressure that they experienced. Hence, we conclude that the Martian atmospheric gases were introduced by shock into the meteoritic material. For the Shergotty minerals, we obtain 3He-, 21Ne-, and 38Ar-based cosmic-ray exposure ages of 3.0 Ma, and for the lherzolite Y-793605, 4.0 Ma, which confirms our earlier conclusion that the lherzolites were ejected from Mars ∼1 Ma before the shergottites. Chassigny yields the previously known ejection age of 11.6 Ma.

— To test different hypotheses of moldavite formation, a major and trace-element study of 25 moldavite tektites and Sm-Nd isotope measurement of three moldavite tektites was completed. The samples were selected from the classical substrewnfields and the newly described locations in Lusatia (Saxony, Germany). Samples with unusual bulk composition were also included. The results confirm earlier studies that the variation in the chemical composition can be explained by single impact and through incomplete mixing of at least three lithographical components dominated by one of the three minerals or mineral groups: dolomite, clay minerals and quartz. An additional endmember, possibly a rare Earth's mantle component, containing high Co, Cr and Ni concentrations is also needed to explain the observed variations in compatible elements of some tektites. Volatile element abundances are low but not necessarily the result of selective volatilization.

We present a study of the noble gas isotopic abundances in two achondrites, Divnoe and the Asuka 881371 angrite. For Divnoe, we also performed chemical analyses of the major elements and of some minor and trace elements that are relevant for the comparison with other meteorite types and for the interpretation of the noble gas data. Based on the cosmic-ray produced noble gases, an exposure age of 5.4 ± 0.7 Ma for Asuka 881371 was obtained. This ejection time from the parent asteroid differs from those of the other three angrites—Angra dos Reis (55.5 Ma), LEW 86010 (17.6 Ma), and LEW 87051 (≥0.2 Ma). Whereas the U,Th- 4 He, and K- 40 Ar gas retention ages of Asuka 881371 are 3750 ± 1000 Ma and 3910 ± 500 Ma, respectively, we derive for the 244 Pu- 136 Xe system, a formation age of 4533 ± 40 Ma, which is contemporaneous with that of the other angrites Angra dos Reis and LEW 86010. For Divnoe the abundance patterns of the major lithophile, siderophile, refractory, and volatile elements, the isotopic abundance pattern for primordial trapped Xe, and the oxygen isotopes indicate that this unique meteorite is related to the brachinite achondrites. Assuming no pre-exposure to cosmic rays on the parent body, Divnoe's asteroid ejection event occurred 17.2 ± 2.3 Ma ago.

— We investigated the characteristics and history of lunar meteorites Queen Alexandra Range 93069, Yamato 793169 and Asuka 881757 based on the abundances of all stable noble gas isotopes, the concentrations of the radionuclides 10Be, 26Al, 36Cl, and 81Kr, and the abundances of Mg, Al, K, Ca, Fe, Cl, Sr, Y, Zr, Ba, and La. Based on the solar wind and cosmic-ray irradiations, QUE 93069 is the most mature lunar meteorite studied up to now. The 40Ar/36Ar ratio of the trapped component is 1.87 ± 0.16. This ratio corresponds to a time when the material was exposed to solar and lunar atmospheric volatiles ∼400 Ma ago. On the other hand, Yamato 793169 and Asuka 881757 contain very little or no solar noble gases, which indicates that these materials resided in the top layer of the lunar regolith only briefly or not at all. For all lunar meteorites, we observe a positive correlation of the concentrations of cosmic-ray produced with trapped solar noble gases. The duration of lunar regolith residence for the lunar meteorites was calculated based on cosmic-ray produced 21Ne, 38Ar, 78Kr, 83Kr, and 126Xe and appropriate production rates that were derived based on the target element abundances and the shielding indicator 131Xe/126Xe. For QUE 93069, Yamato 793169, and Asuka 881757, we obtained 1000 ± 400 Ma, 50 ± 10 Ma, and

Important aspects of boron determination by inductively coupled plasma mass spectrometry are reviewed and extended by additional studies. Determinations on a range of biological materials were performed by external calibration, standard additions and isotope dilution. Memory effects were reduced by rinsing with a wash-solution of sodium fluoride. Accuracy was tested with four biological standard reference materials. Accurate and precise determinations can be achieved with all three modes. The fastest and simplest method is external calibration, where matrix effects can be controlled with beryllium as internal standard. No Improvement resulted with the more laborious standard additions method. The isotope dilution technique requires time-consuming supplementary measurements. Biological material with a boron content 0.06 µg g–1 can be determined.

Investigations were made on the determination of boron in biological material. A procedure using the microwave digestion technique was optimised. The analyses were performed by photometry with azomethine-H, fluorimetry with carminic acid, inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry. The matrix interferences, the interferences caused by iron and the detection limits were investigated for these methods. Determinations were performed for plant material, wheat, milk, meat and blood plasma. Recoveries and precision of all methods were studied. To test accuracy and precision, four NBS reference materials were analysed and the results compared with the values in literature. Good recoveries were found with all methods, except the fluorimetric technique. The boron content found in the NBS standard reference materials agreed well with data reported before. Best precision was obtained for the two ICP methods. The azomethine-H method gave good results when material of high boron content was analysed. With the carminic acid method no reliable results were achieved.

We report the noble gas concentrations and the Al-26, Be-10, Cl-36, and Ca-41 activities of the Antarctic lunar meteorite Elephant Moraine 87521. Although the actual exposure history of the meteorite may have been more complex, the following model history accounts satisfactorily for the cosmogenic nuclide data: A first stage of lunar irradiation for about 1 Ma at a depth of 1-5 g/sq cm followed, not necessarily directly, by a second one for 26 Ma at about 565 g/sq cm; launch from the moon less than 0.1 Ma ago; and arrival on earth 15-50 ka ago. The small concentration of trapped gases shows that except for some material that may have been introduced at the moment of launch, EET 87521 spent less than 1 Ma at a lunar depth less than 1 g/sq cm. EET 87521 has a K/Ar age in the range 3.0-3.4 Ga, which is typical for lunar mare basalts.

Fluorine and iodine were determined in some biological reference materials. Radiochemical neutron activation analysis was used for iodine and ion-selective potentiometry for fluorine. The two elements were separated from the matrix elements by pyrohydrolysis in the presence of vanadium(V) oxide. The volatile compounds were absorbed in sodium hydroxide solution for the determination of fluorine and in acidic silver nitrate solution for the determination of iodine. This method gives low detection limits with small sample sizes.

— Impact glasses, tektites and some related basement rocks were analyzed for F, Cl, Br and I. The tektite and impact glasses show similar abundance patterns within the groups. Muong Nong-type tektites indicate that the halogens have been depleted in the order I > Br > Cl > F in their melt under oxidizing conditions. For Darwin Glass selective volatilization of F from the melt is a major depleting process. Cl, Br and I are lost to a lesser extent.

Aerosols and reactive gases from the spring 1984 eruption of Mauna Loa Volcano on Hawaii were collected and analyzed for osmium and its isotopic composition. The measured187Os/186Os ratio of1.14 ± 0.03 is close to the ratio in matter with solar systemRe/Os abundance. This result shows that the aerosols from Mauna Loa originated in the mantle and that their composition was not or only slightly influenced by their contact with the crust.

The concentrations of fluorine, chlorine, bromine and iodine of seven geochemical reference samples have been determined. Analytical techniques were neutron activation analysis for chlorine, bromine and iodine and ion-selective potentiometry for fluorine. After irradiation of the samples, these halogens were separated from the matrix elements by pyrohydrolysis in presence of vanadium (V) oxide. This extraction allows to measure the four halogens in the same sample.

We measured the titanium (Ti) isotope composition, i.e., 50Ti/47Ti, 48Ti/47Ti, and 46Ti/47Ti, in five calcium-rich-aluminum-rich refractory inclusions (CAIs) from the oxidized CV3 chondrite Allende and in two CAIs from the reduced CV3 chondrite Efremovka. Our data indicate that CAIs are enriched in 50Ti/47Ti and 46Ti/47Ti and are slightly depleted in 48Ti/47Ti compared to normal Ti defined by ordinary chondrites, eucrites, ureilites, mesosiderites, Earth, Moon, and Mars. Some CAIs have an additional 50Ti excess of 8ε relative to bulk carbonaceous chondrites, which are enriched in 50Ti by 2ε relative to terrestrial values, leading to a total excess of 10ε. This additional 50Ti excess is correlated with nucleosynthetic anomalies found in 62Ni and 96Zr, all indicating an origin from a neutron-rich stellar source. Bulk carbonaceous chondrites show a similar trend, however, the extent of the anomalies is either less than or similar to the smallest anomalies seen in CAIs. Mass balance calculations suggest that bulk Allende Ti possibly consists of a mixture of at least two Ti components, anomalous Ti located in CAIs and a normal component possibly for matrix and chondrules. This argues for a heterogeneous distribution of Ti isotopes in the solar system. The finding that anomalous Ti is concentrated in CAIs suggests that CAIs formed in a specific region of the solar system and were, after their formation, not homogeneously redistributed within the solar system. Combining the CAI data with improved model predictions for early solar system irradiation effects indicates that a local production scenario for the relatively short lived radionuclides can be excluded, because the production of, e.g., 10Be, 26Al, and 41Ca, would result in a significant collateral shift in Ti isotopes, which is not seen in the measured data. © 2009. The American Astronomical Society. All rights reserved.

The original mass (15915 g) of the Twannberg IIG (low Ni-, high P) iron was found in 1984. Five additional masses (12 to 2488 g) were recovered between 2000 and 2007 in the area. The different masses show identical mineralogy consisting of kamacite single crystals with inclusions of three types of schreibersite crystals: cm-sized skeletal (10.5% Ni), lamellar (17.2% Ni), and 1-3 x 10 μm-sized microprismatic (23.9% Ni). Masses I and II were compared in detail and have virtually identical microstructure, hardness, chemical composition, cosmic-ray exposure (CRE) ages, and 10Be and 26Al activities. Bulk concentrations of 5.2% Ni and 2.0% P were calculated. The preatmospheric mass is estimated to have been at least 11,000 kg. The average CRE age for the different Twannberg samples is 230 ± 50 Ma. Detrital terrestrial mineral grains in the oxide rinds of the three larger masses indicate that they oxidized while they were incorporated in a glacial till deposited by the Rhone glacier during the last glaciation (Wrm). The find location of mass I is located at the limit of glaciation where the meteorite may have deposited after transport by the glacier over considerable distance. All evidence indicates pairing of the six masses, which may be part of a larger shower as is indicated by the large inferred pre-atmospheric mass.

129 I is preconcentrated from environmental samples and its accessibility is addressed for inductively coupled plasma quadrupole mass spectrometer with collision/reaction interface (ICP-CRI-QMS). By applying oxygen as CRI gas through skimmer cone, the signal of the interfering 129 Xe from the impurity of plasma gas can be eliminated while the formation of 127 I 1 H 1 H + can be partially removed. The improved ICP-QMS can be employed for investigation of 129 I in environmental samples with a 129 I/ 127 I ratio down to 10 -7 . The detection capability was demonstrated by measuring 129 I in seaweed samples collected around the nuclear fuel reprocessing plant at La Hague. The abundant 127 I in the sample matrix causes a serious problem and degrades the detection capability of the instrument when the concentration of 127 I is larger than 10 5 ng/g. Even combined with a sufficient pre-concentration procedure, ICP-QMS is not considered as a suitable technique for the analysis of 129 I in uncontaminated environmental samples with 129 I/ 127 I ratio of less than 10 -7 . Results are presented for seaweed samples collected around La Hague. In addition, time dependant I concentrations and ratios are given for colloids and water sampled from Lake Thun.