Bernd Kober

Imperial College London, London, ENG, United Kingdom

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Publications (27)45.81 Total impact

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    ABSTRACT: The phasing out of leaded gasoline in many countries around the world at the end of the last millennium has resulted in a complex mixture of lead sources in the atmosphere. Recent studies suggest that coal combustion has become an important source of Pb in aerosols in urban and remote areas. Here, we report lead concentration and isotopic composition for 59 coal samples representing major coal deposits worldwide in an attempt to characterize this potential source. The average concentration in these coals is 35 microg Pb g(-1), with the highest values in coals from Spain and Peru and the lowest in coals from Australia and North America. The 206Pb/207Pb isotope ratios range between 1.15 and 1.24, with less radiogenic Pb in coals from Europe and Asia compared to South and North America. Comparing the Pb isotopic signatures of coals from this and previous studies with those published for Northern and Southern Hemisphere aerosols, we hypothesize that coal combustion might now be an important Pb source in China, the eastern U.S., and to some extent, in Europe but not as yet in other regions including South Africa, South America, and western U.S. This supports the notion that "old Pb pollution" from leaded gasoline reemitted into the atmosphere or long-range transport (i.e., from China to the western U.S.) is important. Comparing the isotope ratios of the coals, the age of the deposits, and Pb isotope evolution models for the major geochemical reservoirs suggests that the PbIC in coals is strongly influenced by the depositional coal forming environment.
    Environmental Science and Technology 03/2009; 43(4):1078-85. · 5.26 Impact Factor
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    ABSTRACT: Environmental archives like peat deposits allow for the reconstruction of both naturally and anthropogenically forced changes in the biogeochemical cycle of Pb as well as the quantification of past and present atmospheric Pb pollution. However, records of atmospheric Pb deposition from pre-industrial times are lacking.In a publication by Weiss et al. [Weiss, D., Shotyk, W., Boyle, E.A., Kramers, J.D., Appleby, P.G., Cheburkin, A.K., Comparative study of the temporal evolution of atmospheric lead deposition in Scotland and eastern Canada using blanket peat bogs. Sci Total Environ 2002;292:7–18]. Pb isotopes data measured by Q-ICP-MS and TIMS, concentration and enrichment data was presented for sites in eastern Canada (PeW1) and northwestern Scotland (LL7c), dating to 1586 A.D and 715 A.D., respectively. Here these same cores are re-analysed for Pb isotopes by MC-ICP-MS thereby acquiring 204Pb data and improving on the original data in terms of resolution and temporal coverage. Significant differences were found between the Q-ICP-MS/TIMS and MC-ICP-MS measurements, particularly at PeW1. These discrepancies are attributed to the problematic presence of organic matter during sample preparation and analysis complicated by the heterogeneity of the organic compounds that survived sample preparation steps. The precision and accuracy of Pb isotopes in complex matrices like peat is not always well estimated by industrial standards like NIST-SRM 981 Pb.Lead pollution histories at each site were constructed using the MC-ICP-MS data. The entire LL7c record is likely subject to anthropogenic additions. Contributions from local mining were detected in Medieval times. Later, coal use and mining in Scotland, Wales and England became important. After industrialization (ca. 1885 A.D.) contributions from Broken Hill type ores and hence, leaded petrol, dominate atmospheric Pb signatures right up to modern times. At PeW1 anthropogenic impacts are first distinguishable in the late 17th century with the mining and use of local coal. After industrialization (ca. 1810 A.D.), coal and petrol are the main Pb sources. A comprehensive estimate of the natural atmospheric background 206Pb/207Pb signature in eastern Canadian aerosols is made with a value of ~ 1.19.
    Science of The Total Environment 01/2009; 407(5):1644-1657. · 3.26 Impact Factor
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    ABSTRACT: The compositional zoning of plagioclase-mantled K-feldspar, defining the rapakivi texture, and of the associated quartz phenocrysts from the Paleozoic Land’s End (U.K.) and Altenberg–Frauenstein (Germany) granites, and the Proterozoic Hammarudda (Finland) granite porphyry, has been investigated by laser-ablation – inductively coupled plasma – mass spectrometry, electron-probe micro-analyses, cathodoluminescence and thermal ionization mass spectrometry in order to investigate the formation of the rapakivi texture in two different eons. Recent analytical developments and the Ti-in-quartz geothermometer lead to interpretations of the trace-element zoning in quartz phenocrysts coexisting with rapakivi feldspars. There is an approximate coincidence with Ba-rich growth zones in plagioclase-mantled K-feldspar and Ti-rich zones in coexisting quartz phenocrysts. Both types of zoning indicate increasing temperatures of crystallization. The formation of the plagioclase mantles seems to be related to quartz-resorption events. The inferred temperature of crystallization increased after marginal resorption of quartz phenocrysts by about 82°C in the Altenberg–Frauenstein magma and 44°C in the Hammarudda magma, on the basis of the Ti-inquartz geothermometer. The temperature increase is correlated positively with the crystallization of plagioclase mantles on the K-feldspar. The quartz phenocryst in the Land’s End granite shows normal core-to-rim zoning of Ti (decreasing concentrations), indicating a gradual decrease in magma temperature. We contend that the increase in the quartz-crystallization temperature of >25°C after a resorption event is indicative for the interaction with mafic magma. Therefore, the interaction of a crystal-saturated granitic magma and a mafic magma is the driving force causing nucleation and crystallization of plagioclase on K-feldspar phenocrysts, even though the Pb isotope, Ba, Sr, and Rb zoning of the mantled K-feldspar phenocryst have not clearly recorded an interaction between granitic and mafic magmas. The frequency of rapakivi feldspars in the rock correlates with the portion of mafic magma involved in the mingling and mixing process. Isothermal decompression during adiabatic magma ascent may have contributed to the plagioclase mantle formation in the case of the Altenberg–Frauenstein and Hammarudda granites. The rare rapakivi feldspars in the Land’s End granite developed during an early stage of magmatic evolution; as a result, tracing the conditions of formation of the rapakivi texture is speculative in that case.
    The Canadian Mineralogist 06/2008; 46:1417-1442. · 1.18 Impact Factor
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    ABSTRACT: ABSTR ACT The elemental compositions of zoned alkali feldspar megacrysts from the Karkonosze pluton have been analysed and lead isotope ratios determined using LA-ICP-MS, EMPA and TIMS. The results are used to interpret the magmatic environments within which they crystallized. Growth zones in the megacrysts show fluctuating trace element patterns that reflect a systematic relationship between incompatible LREE and compatible Ba. Chemical gradients between zones in the cores and rims of the megacrysts are not accompanied by significant variation in initial Pb isotope composition. The nucleation and crystallization of the megacrysts is interpreted as having occurred in an environment of magmatic hybridization caused by mixing of mantle and crustal components in which effective homogenization of the Pb isotope composition preceded the onset of megacryst growth. The concentrations of LREE in alkali feldspar zones were used to reconstruct hypothetical melt compositions. Some of the zones appear to have crystallized in a homogenous magmatic environment having clear geochemical affinities with end-member magmas in the Karkonosze pluton, whereas others crystallized in heterogeneous domains of magma hybridization. With the exception of Nd, zones crystallized in more homogeneous magma show LREE fractionation under near-equilibrium conditions. Trace element abundances of megacrysts grown in dynamic, homogeneous magmatic environments of the Karkonosze pluton occasionally deviate from the predicted patterns and show LREE impoverishment.
    Mineralogical Magazine. 07/2007; 71(2):193–217.
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    ABSTRACT: The elemental compositions of zoned alkali feldspar megacrysts from the Karkonosze pluton have been analysed and Pb isotope ratios determined using LA-ICP-MS, EMPA and TIMS. The results are used to interpret the magmatic environments within which they crystallized. Growth zones in the megacrysts show fluctuating trace element patterns that reflect a systematic relationship between incompatible LREE and compatible Ba. Chemical gradients between zones in the cores and rims of the megacrysts are not accompanied by significant variation in initial Pb isotope composition. The nucleation and crystallization of the megacrysts is interpreted as having occurred in an environment of magmatic hybridization caused by mixing of mantle and crustal components in which effective homogenization of the Pb isotope composition preceded the onset of megacryst growth. The concentrations of LREE in alkali feldspar zones were used to reconstruct hypothetical melt compositions. Some of the zones appear to have crystallized in an homogenous magmatic environment having clear geochemical affinities with end-member magmas in the Karkonosze pluton, whereas others crystallized in heterogeneous domains of magma hybridization. With the exception of Nd, zones crystallized in more homogeneous magma show LREE fractionation under near-equilibrium conditions. Trace element abundances of megacrysts grown in dynamic, homogeneous magmatic environments of the Karkonosze pluton occasionally deviate from the predicted patterns and show LREE impoverishment.
    Mineralogical Magazine 06/2007; 24:155-178. · 2.21 Impact Factor
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    ABSTRACT: An analytical protocol for rapid and reliable laser ablation-quadrupole (LA-Q)- and multi-collector (MC-) inductively coupled plasma-mass spectrometry (ICP-MS) analysis of Pb isotope ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb) in peats and lichens is developed. This technique is applicable to source tracing atmospheric Pb deposition in biomonitoring studies and sample screening. Reference materials and environmental samples were dry ashed and pressed into pellets for introduction by laser ablation. No binder was used to reduce contamination. LA-MC-ICP-MS internal and external precisions were <1.1% and <0.3%, respectively, on both (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios. LA-Q-ICP-MS internal precisions on (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios were lower with values for the different sample sets <14.3% while external precisions were <2.9%. The level of external precision acquired in this study is high enough to distinguish between most modern Pb sources. LA-MC-ICP-MS measurements differed from thermal ionisation mass spectrometry (TIMS) values by 1% or less while the accuracy obtained using LA-Q-ICP-MS compared to solution MC-ICP-MS was 3.1% or better using a run bracketing (RB) mass bias correction method. Sample heterogeneity and detector switching when measuring (208)Pb by Q-ICP-MS are identified as sources of reduced analytical performance.
    Analytica chimica acta 02/2007; 582(1):116-24. · 4.31 Impact Factor
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    ABSTRACT: Sr isotope and Ca/Mg/Sr chemical compositions of freshwater ostracode tests separated from a sediment core represent the last 16 ka of sedimentation in Lake Constance, Central Europe. The chemical evolution of the paleowater's dissolved load of Lake Constance was estimated by correcting the ostracode data for Ca/Mg/Sr fractionation due to biogenic calcification. Since the Late Pleistocene deglaciation, the Ca/Sr molar ratios of paleowaters increased systematically from about 100 (a near marine signature) to about 200. Ca/Mg molar ratios varied in the range of 1–25. The 87Sr/86Sr ratios indicate Late Pleistocene paleowater compositions of 0.7086–0.7091, significantly more radiogenic than present day waters (0.7085). Sr isotopes and Ca/Mg/Sr chemical data together show that weathering of Mesozoic evaporites consistently dominated the dissolved Sr load (80–90%). Carbonate and silicate weathering were less important (1–10%). Trends of Sr dissolved loads were therefore not related to Mg which was mainly mobilized by carbonate weathering. Biotite weathering was an important source of radiogenic Sr in the paleowaters. The short-term release (duration about 600–800 years) of radiogenic Sr during glacier retreat started 15.2 ka ago and was due to enhanced biotite weathering at the glacier base. Long-term release of radiogenic Sr was due to biotite weathering in glacial soils and silicate rocks, and has gradually declined since the Late Pleistocene/Holocene transition.
    Chemical Geology. 01/2007;
  • Mineralogical Magazine. 01/2007; 71:193-217.
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    ABSTRACT: The fate of the Rare Earth Elements (REE) were investigated in different types of archives of atmospheric deposition in the Black Forest, Southern Germany: (1) a 70 cm snow pack collected on the domed part of a raised bog and representing 2 months of snow accumulation, (2) a snow sample collected close to the road about 500 m from the peat bog, (3) two species of lichens and (4) a peat profile representing 400 years of peat accumulation as well as a “preanthropogenic” sample and the living moss layer from the top of the core. REE concentrations in peat are significantly correlated to Ti which is a lithogenic conservative element suggesting that REE are immobile in peat bog environments. Snow, lichens and peat samples show similar PAAS (Post Archean Australian Shale) normalized REE distributions suggesting that the complete atmospheric REE signal is preserved in the peat profile. However, the annual flux of REE accumulated by the peat is ca. 10 times greater than that of the bulk winter flux of REE. This difference probably indicates that the REE concentrations in the snowpack are not representative of the average REE flux over the whole year. Despite the pronounced geological differences between this site (granite host-rock) and a previously studied peat bog in Switzerland (limestone host-rock) similar REE distribution patterns and accumulation rates were found at both sites. Given that both sites confirm an Upper Continental Crust signature, the data suggests both sites are influenced by regional and not local, soil-derived lithogenic aerosols.
    Geochimica et Cosmochimica Acta 01/2006; · 3.88 Impact Factor
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    ABSTRACT: Episodic and localized illite mineralization is documented in the hydrothermally altered Soultz-sous-Forêts granite (Upper Rhine Graben, France). Separated grain-size fractions of altered granite and argillite vein samples contain mixtures of 2M1 and 1M trans-vacant illite varieties. The platy pseudohexagonal 2M1 illite phases dominate the vein fillings, whereas the 1M illite occurs largely as a fibrous pore-filling variety, which is particularly abundant in the granite matrix. Multiple phases of fluid injections into the granite body have resulted in different illite assemblages, each sample containing a mixture of polytype generations formed during different crystal growth events. On the basis of mineralogical and K–Ar isotopic constraints, the ages of these vein-mineralizing events are determined by plotting the K–Ar values of the various grain-size fractions against polytype abundance and the fitted volume-weighted crystallite thickness distributions. The results suggest a Permian age for the formation of the studied argillite veins, characterized by successive injections of hydrothermal fluids. Secondary episodes of illite crystallization occurred during Jurassic and Cretaceous (or even younger times) in both the veins and the granite matrix. There are indications that the polytype structure and composition of illite were strongly influenced by variations in fluid chemistry and the degree of fluid–rock interaction as the granite was progressively sealed during post-Variscan, episodic hydrothermal activity.
    Contributions to Mineralogy and Petrology 01/2006; 152(3):349-364. · 3.48 Impact Factor
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    ABSTRACT: Travertine and calcareous tufa deposits, are important archives for Quaternary continental climate and archaeology. Here we present a comprehensive study on Holocene travertine deposition in the Thuringia basin based on a detailed survey of U-series measurements and dating that demonstrates rapid accumulation of carbonate during the early Holocene until 8000 years (up to 8 mm yr–1) followed by significant change in travertine accumulation that ended around 5800 years BP at the investigated site. We further demonstrate that systematic changes of the U-isotopic composition through time occur in agreement with major changes in travertine accumulation and texture, which are likely to reflect changes of spring water U-isotopic composition rather than U-series system opening or contamination with non-carbonate particles.
    01/2006;
  • Applied Geochemistry 01/2006; 21:563. · 1.71 Impact Factor
  • European Journal of Mineralogy 01/2006; (submitted). · 1.25 Impact Factor
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    ABSTRACT: Element concentrations, element ratios and Pb and Zn isotope data are reported for different geologic samples (barren and ore-bearing granites and host rocks), technogenic products (ore concentrates and tailings) and biologic samples (lichens and birch leaves) from the Orlovka–Spokoinoe mining district, Eastern Transbaikalia, Russia, with the aim to trace the sources of Pb and Zn at a local level within the mining site. Lichens and birch leaves were used as receptors of contamination within the mining site. Pb/Zr and Zn/Zr values indicated Pb and Zn enrichment relative to host rocks. Zn isotope data of 15 geologic and 11 lichen samples showed different Zn isotopic signatures with the total range for the geologic suite of −0.4‰ to +1.2‰ and for lichens of +0.4‰ to +1.4‰ in δ66Zn relative to Lyon JMC Zn standard. The source of isotopically heavy Zn within the Orlovka–Spokoinoe mining site could be potentially associated with long-range atmospheric aerosols that also contributed Pb to the studied mining site. Our results demonstrated that Zn isotopes might be used as new tools for Zn source assessment.
    Applied Geochemistry. 01/2006;
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    ABSTRACT: In a peat bog from Black Forest, Southern Germany, the rate of atmospheric Pb accumulation was quantified using a peat core dated by 210Pb and 14C. The most recent Pb accumulation rate (2.5 mg m−2 y−1) is similar to that obtained from a snowpack on the bog surface, which was sampled during the winter 2002 (1 to 4 mg m−2 y−1). The Pb accumulation rates recorded by the peat during the last 25 yr are also in agreement with published values of direct atmospheric fluxes in Black Forest. These values are 50 to 200 times greater than the “natural” average background rate of atmospheric Pb accumulation (20 μg m−2 y−1) obtained using peat samples from the same bog dating from 3300 to 1300 cal. yr B.C. The isotopic composition of Pb was measured in both the modern and ancient peat samples as well as in the snow samples, and clearly shows that recent inputs are dominated by anthropogenic Pb. The chronology and isotopic composition of atmospheric Pb accumulation recorded by the peat from the Black Forest is similar to the chronologies reported earlier using peat cores from various peat bogs as well as herbarium samples of Sphagnum and point to a common Pb source to the region for the past 150 years. In contrast, Pb contamination occurring before 1850 in southwestern Germany, differs from the record published for Switzerland mainly due to the mining activity in Black Forest. Taken together, the results show that peat cores from ombrotrophic bogs can yield accurate records of atmospheric Pb deposition, provided that the cores are carefully collected, handled, prepared, and analysed using appropriate methods.
    Atmospheric Environment 11/2005; 39(36):6790–6801. · 3.11 Impact Factor
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    ABSTRACT: This study focuses on the relationship between U- and Th-isotope distribution, and the porosity/permeability structure of a geological fault in the uplifted Rhine Graben shoulder (SW-Germany). This fault, known as the Schauenburg Fault, separates basement Variscan granite from Permian rhyolite, and is marked by a clay-bearing cataclasite. All fault rock samples are characterized by the redistribution of uranium and thorium isotopes within the last ∼106years, whereas in the granite and the rhyolite only uranium isotopes leaching (activity ratio 1, record a complex history of sorption and loss of uranium isotopes. The uranium activity ratios are higher for the samples collected close to the fault plane and lower for cataclastically deformed fault rock situated away from the principal displacement surface. The porosity measurements of the cataclasite show symmetrical variations across the core of the fault zone, similar to the pattern of uranium activity ratios. In order to relate the porosity data with the δ234U value, a simple exchange model was developed assuming that the change in the uranium activity ratios results from uranium isotopic exchange with the aqueous phase. Best approximations were obtained by using an isotopic water/rock exchange coefficient for 234U ranging from 2.5E−06 [a−1] in the core of the fault zone to 2.5E−05 [a−1] for the fault walls, whereby the isotopic water/rock exchange per year is the same dimension as the radioactive decay constant. Along the outer core of the fault zone, the increased porosity, and thus permeability, resulted in prolonged contact between water and rock. Here, a higher isotopic exchange of uranium with the aqueous phase has occurred. Within the core of the fault, the porosity is lower and the availability of circulating fluids restricted the exchange of uranium isotopes between the rock and the aqueous phase. The resulting exchange time for the isotopic exchange coefficient is 70ka, which suggests a young fluid–rock interaction event possibly related to the last stage of Rhine graben fault activity along this structure.
    Physics and Chemistry of The Earth - PHYS CHEM EARTH. 01/2005; 30(17):1030-1037.
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    ABSTRACT: A peat core from Lindow bog near Manchester, England, was precisely cut into 2 cm slices to provide a high-resolution reconstruction of atmospheric Pb deposition. Radiocarbon and (210)Pb age dates show that the peat core represents the period ca. 2000 BC to AD 1800. Eleven radiocarbon age dates of bulk peat samples reveal a linear age-depth relationship with an average temporal resolution of 18.5 years per cm, or 37 years per sample. Using the Pb/Ti ratio to calculate the rates of anthropogenic, atmospheric Pb deposition, the profile reveals Pb contamination first appearing in peat samples dating from ca. 900 BC which clearly pre-date Roman mining activities. Using TIMS, MC-ICP-MS, and SF-ICP-MS to measure the isotopic composition of Pb, the (208)Pb/(206)Pb and (206)Pb/(207)Pb data indicate that English ores were the predominant sources during the pre-Roman, Roman, and Medieval Periods. The study shows that detailed studies of peat profiles from ombrotrophic bogs, using appropriate preparatory and analytical methods, can provide new insight into the timing, intensity, and predominant sources of atmospheric Pb contamination, even in samples dating from ancient times.
    Journal of Environmental Monitoring 06/2004; 6(5):502-10. · 2.09 Impact Factor
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    ABSTRACT: Four metasedimentary zircon populations from different tectonometamorphic units of the Central and the Northern Schwarzwald (Variscan belt, SW-Germany) were investigated using SEM, cathodoluminescence and SHRIMP dating. Despite partially strong modifications of primary internal morphologies during Variscan metamorphism at amphibolite (750C, 0.4–0.6GPa) and granulite-facies conditions (950–1,000C, 1.4–1.8GPa), many grains show well-preserved protolith ages. The detritus indicates a northern Gondwana origin and different Palaeozoic episodes of sediment deposition and consolidation. Two of the studied sediments were deposited in Cambrian/early-Ordovician times and consolidated in positions close to northern Gondwana. Late Ordovician and rare Devonian detritus from sediments of two other tectonometamorphic units indicates much later sedimentation close to the leading edge of Gondwana or a terrane assemblage during northern drift towards Laurussia. Subsolidus growth of new zircon due to Variscan granulite facies metamorphism of one of the tectonometamorphic units is precisely dated at 3352Ma.
    Contributions to Mineralogy and Petrology 04/2004; 147(3):330-345. · 3.48 Impact Factor
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    ABSTRACT: Element concentrations and Pb isotope data are reported for the Khangilay, Orlovka and Spokoinoe granite massifs and their host rocks in the Orlovka–Spokoinoe mining district, Eastern Transbaikalia, Russia. The aim of the paper is to characterise the evolution trends and geochemical features of the Khangilay pluton and the Orlovka and Spokoinoe deposits and to study the genesis of the three granite massifs by examining fluid–rock and crust–mantle interaction in the evolution of granitoid magmatism. Zr/Hf, Y/Ho and Rb/Sr demonstrate that all three granite bodies show a continuous fractionation history from parental biotite–muscovite granites of Khangilay to highly evolved ore-bearing amazonite granites of Orlovka. Khangilay and its derivates Spokoinoe and Orlovka represent different evolution stages. REE patterns of the amazonite granites of Orlovka show a stronger Eu anomaly and more apparent REE tetrad effects in comparison with the less evolved granites of Khangilay. Pb isotope analyses indicate one common Pb source for all three granite massifs reflecting a homogenous source melt from which all magmatic members generated. Based on Pb isotope systematics two possible scenarios for the source of Li–F granites are proposed: (i) a crust–mantle source where a mixture of MORB and continental-derived material were brought together in the orogenic environment; and (ii) type II enriched mantle source where subducted continental material could have been strongly implicated in volcanic suites.
    Applied Earth Science IMM Transactions section B 03/2004; 113(1):83-99.
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    ABSTRACT: Analytical protocols for accurate and precise Pb isotope ratio determinations in peat, lichen, vegetable, chimney dust, and ore-bearing granites using MC-ICP-MS and their application to environmental studies are presented. Acid dissolution of various matrix types was achieved using high temperature/high pressure microwave and hot plate digestion procedures. The digests were passed through a column packed with EiChrom Sr-resin employing only hydrochloric acid and one column passage. This simplified column chemistry allowed high sample throughput. Typically, internal precisions for approximately 30 ng Pb were below 100 ppm (±2σ) on all Pb ratios in all matrices. Thallium was employed to correct for mass discrimination effects and the achieved accuracy was below 80 ppm for all ratios. This involved an optimization procedure for the ratio using least square fits relative to certified NIST-SRM 981 Pb values. The long-term reproducibility (±2σ) for the NIST-SRM 981 Pb standard over a 5-month period (35 measurements) was better than 350 ppm for all ratios. Selected ore-bearing granites were measured with TIMS and MC-ICP-MS and showed good correlation (e.g., r=0.999 for ratios, slope=0.996, n=13). Mass bias and signal intensities of Tl spiked into natural (after matrix separation) and in synthetic samples did not differ significantly, indicating that any residual components of the complex peat and lichen matrix did not influence mass bias correction. Environmental samples with very different matrices were analyzed during two different studies: (i) lichens, vegetables, and chimney dust around a Cu smelter in the Urals, and (ii) peat samples from an ombrotrophic bog in the Faroe Islands. The presented procedure for sample preparation, mass spectrometry, and data processing tools resulted in accurate and precise Pb isotope data that allowed the reliable differentiation and identification of Pb sources with variations as small as 0.7% for .
    International Journal of Mass Spectrometry. 01/2004; 232(3):205-215.

Publication Stats

239 Citations
45.81 Total Impact Points

Institutions

  • 2009
    • Imperial College London
      • Department of Earth Science and Engineering
      London, ENG, United Kingdom
  • 2004–2009
    • Heidelberg University
      • Institute of Earth Sciences
      Heidelburg, Baden-Württemberg, Germany
  • 2007
    • Technische Universität Braunschweig
      Brunswyck, Lower Saxony, Germany
  • 1999
    • Universität Konstanz
      Constance, Baden-Württemberg, Germany