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Abstract: The objective of this study was to determine the sources of in groundwater of the Olkusz–Zawiercie Major Groundwater Body. The quality of groundwater was relatively good in the past, but fluctuations of the water table level have caused degradation of water quality. Variations in the water table level and the formation of the depression cone have resulted from both groundwater withdrawal and Zn–Pb mine dewatering. As a result within the extended vadose zone of the aquifer, weathering of pyrite and accompanying sulfides has taken place. Since 1992 the water table has risen and this process has been associated with an increase in concentrations of , Ca and Mg. At the same time, the pH has decreased and periodically high Fe concentrations have been detected. High concentrations of Mg and Sr have been observed and, since gypsum layers are known to be present, a de-dolomitisation process has been hypothesized. The PHREEQC program for Windows was used to estimate saturation indices for calcite, dolomite, gypsum and epsomite. Isotopic data for dissolved in the groundwater and archival data on isotopic composition of ore sulfides were used to solve the isotope balance equation and to estimate the fraction of dissolved that originated from pyrite oxidation and gypsum dissolution. The results have shown that dissolution of pyrite oxidation products has a significant influence on chemical composition of groundwater, especially in the southern part of the cone of depression. By solving the additional, combined mass transfer and isotope balance equations it was inferred that a variation in isotopic composition of weathered sulfides must also occur. [ABSTRACT FROM AUTHOR]

Refinements have been made to achieve over 99% yield in the conversion of CO to CO2 in order to improve the reproducibility and accuracy of δ18 O measurements in sulfates. BaSO4 (10-15 mg) was mixed with an identical amount of spectrographic-grade graphite and loaded into a Pt boat. The mixture was gradually heated to 1100 °C to reduce sulfate to CO and CO2; the former gas was simultaneously converted to CO2 by a glow discharge between Pt electrodes immersed in a magnetic field (produced by a pair of external neodymium magnets). A small memory effect was noticed during the analysis (less than 0.3‰ per 10‰ difference in δ18 O between two subsequently analysed samples). The memory effect, however, was suppressed by repetitive preparation of the same specimen. CO2 produced in this way from sulfate reference samples was analysed on a dual inlet and triple collector mass spectrometer along with CO2 equilibrated with VSMOW, GISP and SLAP water reference samples. To avoid large departures of measured isotope ratios from 18O/16O of the working calibrator we used CO2 gas prepared from ocean water sulfate for this purpose. The calibrated δ18 O values (in ‰) obtained in this way for NBS-127, IAEA SO-5 and IAEA SO-6 reference materials were 8.73 ± 0.05, 12.20 ± 0.07 and -10.43 ± 0.12, respectively. [ABSTRACT FROM AUTHOR]

Development of glaciolacustrine basins and varved clay sedimentation in Lithuania are closely connected with the course of ice retreat during Daniglacial time from 16,000 till 13,000 BE Isotopic composition (δ13C and δ18O) of chemogenic carbonaceous samples from glaciolacustrine varved clays, which spread near glacier edge of South-Lithuanian (Balbieriškis section), Middle-Lithuanian (Girininkai section) and North-Lithuanian (Joniškêlis section) Phases of the Baltija (Pomeranian) Stage of Nemunas (Vistulian) Glaciation, has been studied. The obtained stable isotope data well confirm climatic changes of Daniglacial time in Lithuania. The gradual warming of climate is connected with the South-Lithuanian to Middle- Lithuanian and the Middle-Lithuanian to North-Lithuanian Interphasials as well as with the South Lithuanian interoscillations. The Interphasial lacustrine sedimentation with rhythmical lamination of carbonaceous sediments was observed in the middle part of the Balbieriškis section (at a depth of 3.1-5.9 m). The following climatic changes of Daniglacial time in Lithuania are distinguished: (1) stadial (3000-6000), (2) glaciophasial (500-1000), (3) glacio- oscillation (500-1000) years and (1) interstadial (1000-2000), (2) interphasial (250-450), (3) glacio-interoscillation (20-40) years. Regular succession of Daniglacial climatic and sedimentation changes in the local periglacial glaciolacustrine lakes, conditioned by recession of the last Scandinavian ice sheet, was revealed in the glaciolacustrine-lacustrine sediments for the first time. [ABSTRACT FROM AUTHOR]

Presents a study which discussed the use of Cu2O - NaPO3 mixtures for sulfur dioxide extraction from BaSO4 for sulfur isotope analysis. Method to extract sulfur dioxide from sulfates; Assessment of the amount of extracted sulfur dioxide and reaction time; Information on the plots of sulfur dioxide yield as a function of reaction time.

Temporal and spatial variations of the concentration and the isotopic composition of groundwater sulfate in an unconfined sandy aquifer covered by peatland have been studied to better understand the sources and biogeochemical processes that affect sulfate distribution in shallow groundwater systems influenced by organic rich sediments. The groundwater monitoring was carried out for one year at hydrogeological station Pożary located within the protected zone of the Kampinos National Park. Sulfur (δ34SSO4) and oxygen (δ18OSO4) isotopic composition of dissolved sulfates were analyzed together with oxygen (δ18OH2O) and hydrogen (δ2HH2O) isotopic composition of water and major ions concentration at monthly intervals. The research revealed three main sources of sulfates dissolved in groundwater, namely, (a) atmospheric sulfates—supplied to the aquifer by atmospheric deposition (rain and snow melt), (b) sulfates formed by dissolution of evaporite sulfate minerals, mainly gypsum—considerably enriched in 34S and 18O, and (c) sulfate formed during oxidation of reduced inorganic sulfur compounds (RIS), mainly pyrite—depleted in 34S and 18O. The final isotopic composition and concentration of dissolved SO42− in groundwater are the result of overlapping processes of dissimilatory sulfate reduction, oxidation of sulfide minerals, and mixing of water in aquifer profile. [ABSTRACT FROM AUTHOR]

Study of three halite sections in the Ro¨t Basin from the eastern Netherlands (Twente-Rijn 382 borehole), central Germany (Mardorf 6 borehole) and western Poland (Os´no IG2 borehole) shows that the δ34S values in Ro¨t sulphates of studied samples (27.14–31.98‰) are characteristic of marine sulphates of late Early Triassic. These values fit in the Ro¨t event shift described in the literature. The bromine content in halite is 32–158 ppm. In the Dutch and Polish sections, relics of sedimentary structures—chevron and hopper—are recorded in halite grains. These structures contain fluid inclusions that were analysed using the ultramicrochemical method of Petrichenko (Petrichenko, O.I. 1973. Metody doslidzhennya vkluchen' v mineralakh galogennykh porid. Kiev, Naukova Dumka, 92 pp.). In the German section, no sedimentary halite structures occur. Because the pressure in the inclusions in recrystallized halite is only slightly greater than atmospheric pressure, these inclusions are presumed to be early diagenetic in origin.The analysis of individual brine inclusions, both in sedimentary and diagenetic forms of halite, shows that the Ro¨t brines correspond to the Na-K-Mg-Cl-SO4 (SO4-rich) chemical type, i.e. the same type that characterises modern seawater. However, the Ro¨t brines differ from the composition characteristic of modern concentrated seawater by a decrease in the content of sulphate ion and an increase in the content of potassium ion. On a Ja¨necke diagram, the points of the brine composition during deposition of Ro¨t halite in Poland, Germany and the Netherlands only show a small range. This suggests a stable composition of basinal brines during the deposition of the halite. At the same time, the relative content of sulphate ion in the Lower Triassic Ro¨t Basin was slightly lower than that in Upper Permian evaporite basins, but higher than that in Lower and Middle Permian and Middle and Upper Triassic evaporite basins. The implication is that the content of sulphate ion in seawater was subject to changes in Permian and Triassic times. [Copyright &y& Elsevier]

The most precise method of chlorine isotope analysis described to date is based on the isotope ratio mass spectrometry (IRMS) of chlorine quantitatively converted into chloromethane, CH(3)Cl. This gas can be produced from several chlorine-containing compounds and analyzed by IRMS. However, the mass spectrum of chloromethane is rather complicated and the ratio of the most abundant ions (mass-52/mass-50) differs from the (37)Cl/(35)Cl isotope ratio. This difference becomes significant when the delta37 Cl exceeds 10 per thousand. Moreover, the electron ionization source yields approximately 80% of all the ionic species at the useful masses 50 and 52. To overcome these drawbacks, we have devised a negative ion mass spectrometer which retains all the best features of IRMS, including a dual-inlet system with changeover valve, dual collector assembly and CH(3)Cl gas as analyte. In the modified ion source we have replaced the ionization chamber with an electron beam by a metal tube with a hot metal filament inside it. Within this tube the (35)Cl(-) and (37)Cl(-) ions are produced with an efficiency dependent on the filament material and its temperature. No other ionic species were found in the mass spectrum except of traces at masses 26 and 28 at ppm levels, probably due to the formation of CN(-) and CO(-). The minimal amount of Cl used in our method is of the order of 5 micromol (3 mg AgCl) and the precision is better than 0.005 per thousand (1sigma)., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

A slice of black shale rock cut by various metal sulphide veins of different generations from the Kupferschiefer deposits of Lubin, Poland was subjected to bombardment in a Laser Microprobe Combustion Reactor to produce SO2 for S-isotope analyses. The delta34S values ranged from-22 to-29 per thousand consistent with previous findings using conventional IRMS and attributable to primary generation of H2S by bacterial sulphate reduction. Systematic trends in delta34S values of a few per mil over distances of the order of mm attest to low temperatures of mineralization with accompanying change in the isotope composition of the fluids due to kinetic or equilibrium isotope fractionation.