Composition of Kerogen in Kupferschiefer from Southwest Poland

Thirty-seven Kupferschiefer samples from southwestern Poland were analyzed by microscopy, Rock-Eval approach and instrumental neutron activation analysis to understand the geochemical and morphological characteristics of kerogen present in the samples. The analytical results indicate that there are two different types of kerogens. One type was only subjected to thermal alteration processes, and the other was further oxidized after deposition of the sediment.In the oxidized samples migrabitumen was transformed into pyrobitumen. Rock-Eval analyses show a significant decrease in HI values in the oxidized samples and an increase in OI values in relation to the samples that were not influenced by oxidation. Variations in S2 versus Corg contents indicate a change in kerogen from Type II to Type III with progressing oxidation. The presence of pyrobitumen and the depletion of hydrogen in the altered kerogen allow one to conclude that the kerogen was used as hydrogen donor for thermochemical sulfate reduction(TSR).     

The variability of δ34S and sulfur speciation in sediments of the Sulejów dam reservoir (Central Poland)

The study was carried out on the Sulejów dam reservoir (Central Poland). Water and sediment samples were collected between February and October 2006. Sulfur compounds in the sediment were chemically extracted and subjected to isotopic analysis.Large variability of SO₄²⁻ concentration in the water column (from 10.3 to 36.2 mg/dm³) and the isotopic composition of sulfur (δ³⁴S from 2.1 to 5.4‰) was observed. The main identified sources of SO₄²⁻ were watercourses, surface runoff, and phosphorus fertilizers.Both oxidized sulfur species (SO₄²⁻) and its reduced forms were found in sediments. Particular sulfur forms were characterized by large variations in both, concentrations and the isotopic composition of sulfur. SO₄²⁻ in the sediment and in the water column had different genesis. Bacterial oxidation of organic sulfur and its binding in SO₄²⁻ were observed in the sediment. Under reducing conditions, oxidized and organic sulfur is converted to H₂S which reacted with Fe or other metallic ions leading to metal sulfide precipitation. Monosulfides were shown to have a very low concentration, ranging up to 0.07 mg/g of sediment. The transformation of elemental sulfur from sulfides through their chemical oxidation occurred in the sediment.     

Influences of ore formation on biomarkers in the Kupferschiefer from the Lubin mine, Poland

Molecular biomarkers are the important maturity parameters for sedimentary organic matter.They have also been widely used for determining the maturity of organic matter in ore deposits. However,during the study of organic matter in the Kupferschiefer from the Lubin mine, it had been found that the biomarkers were influenced by sulfide formation. In order to probe into the degree of influence on biomarkers, seven samples collected from a Kupferschiefer section from the Lubin mine were analyzed by various geochemical methods. The results indicated that in the samples with higher copper contents, the values of biomarkers are lower than in the samples with lower copper contents. In highly mineralized samples, hydrogen donation for thermochemical sulfate reduction (TSR) occurred in alkylated phenanthrenes and naphthalenes, leading to the decrease of 12 biomarker parameters during the Kupferschiefer mineralization.     

Relationship of polycyclic aromatic sulfur compounds and gold enrichment in the Kupferschiefer from Poland and Germany

1INTRODUCTION ORGANICALLY BOUNDSULFURCOMPOUNDSWEREPREVI OUSLYDETECTEDINTHEKUPFERSCHIEFER(P櫣TTMANNAND GO EL,1990;ROSPONDEKETAL.,1994).P櫣TTMANN ANDGO EL(1990)INVESTIGATEDTHEEXTRACTABLEORGANIC MATTERINTHEKUPFERSCHIEFERFROMTHENORTH SUDETIC SYNCLINEANDPROPOS…     

The Role of Organic Matter During Metal Enrichment in Permian Kupferschiefer of the Rudna Mine,Southwest Poland

The bulk composition of organic matter and saturated and aromatic hydrocarbons extracted from 16 samples collected from two Kuperschiefer profiles in the Rudna mine,Southwest Poland has been analyzed to study the role of organic matter during base metal enrichment in the Kupferschiefer shale.The results indicated that the extract yields and saturated hydrocarbon yields decreased with increasing base metal contents.GC and GC/MS analyses indicated that n -alkanes and alkylated aromatic compounds were depleted and may have served as hydrogen donators for thermochemical sulfate reduction.The enrichment of base metal is closely connected with the destruction of hydrocarbons.     

Different isotopic evolutionary trends of δ34S and δ18O compositions of dissolved sulfate in an anaerobic deltaic aquifer system

Concentration and isotope ratios (δ³⁴S_SO4 and δ¹⁸O_SO4) of dissolved sulfate of groundwater were analyzed in a very large anaerobic aquifer system under the Lower Central Plain (LCP) (25,000 km²) in Thailand. Groundwater samples were collected in two different kinds of aquifers; type 1 with a saline water contribution and type 2 lateritic aquifers with no saline water contribution. Two different isotopic compositional trends were observed: in type 1 aquifers sulfate isotope ratios range from low values (+2.2‰ for δ³⁴S_SO4 and +8.0‰ for δ¹⁸O_SO4) to high values (+49.9‰ for δ³⁴S_SO4 and +17.9‰ for δ¹⁸O_SO4); in type 2 aquifers sulfate isotope ratios range from low values (−0.1‰ for δ³⁴S_SO4 and +12.2‰ for δ¹⁸O_SO4) to high δ¹⁸O_SO4 ratios (+18.4‰) but with low δ³⁴S_SO4 ratios (<+12.9‰). Isotopic comparison with possible source materials and theoretical geochemical models suggests that the sulfate isotope variation for type 1 aquifer groundwater can be explained by two main processes. One is the contribution of remnant seawater, which has experienced dissimilatory sulfate reduction in the marine clay, into recharge water of freshwater origin. This process accounts for the high salinity groundwater. The other process, explaining for the modest salinity groundwater, is the bacterial sulfate reduction of the mixture water between high salinity water and fresh groundwater. Isotopic variation of type 2 aquifer groundwater may also be explained by bacterial sulfate reduction, with slower reduction rate than that of the groundwater with saline water effect. The origin of groundwater sulfate with low δ³⁴S_SO4 but high δ¹⁸O_SO4 is recognized as an important topic to be examined in a future investigation.     

Controls on δ34S and δ18O of dissolved sulfate in aquifers of the Murray Basin,Australia and their use as indicators of flow processes

The usefulness of stable isotopes of dissolved SO₄ (δ³⁴S and δ¹⁸O) to study recharge processes and to identify areas of significant inter-aquifer mixing was evaluated in a large, semi-arid groundwater basin in south-eastern Australia (the Murray Basin). The distinct isotopic signatures in the oxidizing unconfined Murray Group Aquifer and the deeper reducing Renmark Group confined aquifer may be more sensitive than conventional chemical tracers in establishing aquifer connections. δ³⁴S values in the unconfined Murray Group Aquifer in the south and central part of the study area decrease along the hydraulic gradient from 20.8 to 0.3‰. The concomitant increasing SO₄/Cl ratios, as well as relatively low δ¹⁸O_SO4 values, suggest that vertical input of biogenically derived SO₄ via diffuse recharge is the predominant source of dissolved SO₄ to the aquifer. Further along the hydraulic gradient towards the discharge area near the River Murray, δ³⁴S values in the unconfined Murray Group Aquifer increase, and SO₄/Cl ratios decrease, due to upward leakage of waters from the confined Renmark Group Aquifer which has a distinctly low SO₄/Cl and high δ³⁴S (14.9–56.4‰). Relatively positive δ³⁴S and δ¹⁸O_SO4 values, and low SO₄/Cl in the Renmark Group Aquifer is typical of SO₄ removal by bacterial reduction. The S isotope fractionation between SO₄ and HS⁻ of ∼24‰ estimated for the confined aquifer is similar to the experimentally determined chemical fractionation factor for the reduction process but much lower than the equilibrium fractionation (∼70‰) even though the confined groundwater residence time is >300 Ka years. Mapping the spatial distribution of δ³⁴S and SO₄/Cl of the unconfined Murray Group Aquifer provides an indicative tool for identifying the approximate extent of mixing, however the poorly defined end-member isotopic signatures precludes quantitative estimates of mixing fractions.     

Implication of Ultra-high δ34S Values in Pyrite from Manganese Deposits of the Datangpo Stage, Yangtze Platform, China

Please refer to the attachment(s) for more details.     

Similarity between C,N and S stable isotope profiles in European spruce forest soils: implications for the use of δ34S as a tracer

Stable isotope systematics of C, N and S were studied in soils of 5 European forest ecosystems. The sites were located along a North–South transect from Sweden to Italy (mean annual temperatures from +1.0 to +8.5 °C, atmospheric deposition from 2 to 19 kg N ha⁻¹ a⁻¹, and from 6 to 42 kg S ha⁻¹ a⁻¹). In Picea stands, the behavior of C, N and S isotopes was similar in 3 aspects: (1) assimilation favored the lighter isotopes ¹²C, ¹⁴N and ³²S; (2) mineralization in the soil profile left in situ residues enriched in the heavier isotopes ¹³C, ¹⁵N and ³⁴S; and (3) NO₃–N as well as SO₄–S in soil solution was isotopically lighter compared to the same species in the atmospheric input. In this study, emphasis was placed on S isotope profiles which so far have been investigated to a much lesser extent than those of C and N. Sulfate in monthly samples of atmospheric input had systematically higher δ³⁴S ratios than total soil S at the 0–5 cm depth, on average by 4.0‰. Sulfate in the atmospheric input had higher δ³⁴S ratios than in deep (>50 cm) lysimeter water, on average by 3.2‰. Organic S constituted more than 50% of total soil S throughout most of the profiles (0–20 cm below surface). There was a tendency to isotopically heavier organic S and lighter inorganic SO₄–S, with ester SO₄–S heavier than C-bonded S at 3 of the 5 sites. With an increasing depth (0 to 20 cm below surface), δ¹³C, δ¹⁵N and δ³⁴S ratios of bulk soil increased on average by 0.9, 4.2 and 1.6‰, respectively, reflecting an increasing degree of mineralization of organic matter. The isotope effects of C, N and S mineralization were robust enough to exist at a variety of climate conditions and pollution levels. In the case of S, the difference between isotope composition of the upper organic-rich soil horizon (lower δ³⁴S) and the deeper sesquioxide-rich soil horizons (higher δ³⁴S) can be used to determine the source of SO₄ in streams draining forests. This application of δ³⁴S as a tracer of S origin was developed in the Jezeřı́ catchment, Czech Republic, a highly polluted site suffering from spruce die-back. In 1996–1997, the magnitude and δ³⁴S of atmospheric input (20 kg S ha⁻¹ a⁻¹, 5.8‰) and stream discharge (56 kg S ha⁻¹ a⁻¹, 3.5‰) was monitored. Export of S from the catchment was 3 times higher than contemporary atmospheric input. More than 50% of S in the discharge was represented by release of previously stored pollutant S from the soil. Stable isotope systematics of Jezeřı́ soil S (mean of 2.5‰ in the O+A horizon, 4.8‰ in the B horizon, and 5.8‰ in the bedrock) suggests that most of the soil-derived S in discharge must come from the isotopically light organic S present in the upper soil horizon, and that mineralized organically-cycled S is mainly flushed out during the spring snowmelt. The fact that a considerable proportion of incoming S is organically cycled should be considered when predicting the time-scale of acidification reversal in spruce die-back affected areas.     

A δS isoscape of total sulphur in soils across Northern Ireland

A map of the spatial variation in isotopic composition of a substrate, or isoscape, provides a tool to address a range of research questions, such as the use of isotope fingerprinting to identify the origin of compounds. The focus of this study was to establish a soil S isotope map for Northern Ireland in order to investigate spatial variability within the isotopic composition of total soil sulphur (S). The sample resolution was about one sample every 141 km². δ³⁴S values were grouped based on soil type and soil parent material. Total soil S δ³⁴S data were grouped according to soil type, to evaluate whether a soil’s characteristics affect its isotopic composition. Gleyed soils had a mean δ³⁴S value of +6.3 ± 6.1‰, lower than the means for other soil types. A trend towards higher δ³⁴S values (mean δ³⁴S of +13.8 ± 6.0‰) was observed in soils with a high organic matter content. No trends in δ³⁴S value were observed for other soil types. There were no discernible correlations between total soil S δ³⁴S and soil parent material, with the exception of shale and mudstones. The majority of soils derived from shale and mudstones had δ³⁴S values at or close to the mean of +4.9‰. A spatially coherent pattern of relatively high soil total S δ³⁴S values in the west and north, and low in the SE, is discernible in Northern Ireland. Based on the observed spatial distribution, it has been concluded that the quantity and source (anthropogenic or marine) of wet atmospheric S deposition is a controlling factor on regional variation of soil δ³⁴S in Northern Ireland. This S isoscape will assist studies of S cycling in Northern Ireland and may assist in the creation of an ‘isotopic fingerprint’ for a potential ‘input’ source needed to interpret data in traceability studies.     

Chemistry,isotope values (δD, δ18O, δ34SSO4) and temperatures of the water inflows in two Gotthard tunnels,Swiss Alps

Water inflows in the Gotthard Highway Tunnel and in the Gotthard Exploration Tunnel are meteoric waters infiltrating at different elevations, on both sides of an important orographic divide. Limited interaction of meteoric waters with gneissic rocks produces Ca–HCO₃ and Na–Ca–HCO₃ waters, whereas prolonged interaction of meteoric waters with the same rocks generates Na–HCO₃ to Na–SO₄ waters. Waters circulating in Triassic carbonate-evaporite rocks have a Ca–SO₄ composition. Calcium-Na–SO₄ waters are also present. They can be produced through interaction of either Na–HCO₃ waters with anhydrite or Ca–SO₄ waters with a local gneissic rock, as suggested by reaction path modeling. An analogous simulation indicates that Na–HCO₃ waters are generated through interaction of Ca–HCO₃ waters with a local gneissic rock. The two main SO₄-sources present in the Alps are leaching of upper Triassic sulfate minerals and oxidative dissolution of sulfide minerals of crystalline rocks. Values of δ³⁴S_SO4 < ∼+9‰ are due to oxidative dissolution of sulfide minerals, whereas δ³⁴S_SO4 >∼+9‰ are controlled either by bacterial SO₄ reduction or leaching of upper Triassic sulfate minerals. Most waters have temperatures similar to the expected values for a geothermal gradient of 22°C/km and are close to thermal equilibrium with rocks. However relatively large, descending flows of cold waters and ascending flows of warm waters are present in both tunnels and determine substantial cooling and heating, respectively, of the interacting rocks. The most import upflow zone of warm, Na-rich waters is below Guspisbach, in the Gotthard Highway Tunnel, at 6.2–9.0 km from the southern portal. These warm waters have equilibrium temperatures of 65–75°C and therefore constitute an important low-enthalpy geothermal resource.     

Compound specific δD values of long chain n-alkanes derived from terrestrial higher plants are indicative of the δD of meteoric waters: Evidence from surface soils in eastern China

The stable carbon and hydrogen isotope composition of higher plant-derived long chain n-alkanes (δ¹³C_n-alkanes and δD_n-alkanes) from 45 surface soil samples (within well characterized vegetation zones) from eastern China (18°N–50°N) are reported. The weighted average δD_n-alkanes value for n-C₂₇, n-C₂₉ and n-C₃₁ in the samples and the annual average δD of meteoric water recorded at 12 weather stations proximal to the sampling sites show similar spatial variations. The δD of n-alkanes shows a gradual depletion in value with increasing latitude. The results demonstrate that, on a large spatial scale, the δD values of long chain n-alkanes derived from higher plants have the potential to record the δD of meteoric water, although many other factors can also influence the isotope values. There appears to be no apparent relationship between the δD of the n-alkanes extracted from the surface soil and the overlying vegetation type (i.e. forest/grassland or C₃/C₄ composition). Therefore, palaeoenvironmental studies utilizing δD_n-alkanes from higher plant-derived material in geological samples have the potential to provide additional information with regard to the past hydrological cycle.     

The occurrences of the rare earth elements and the platinum group elements in relation to base metal zoning in the vicinity of Rote Fäule in the Kupferschiefer of Poland

The concentrations of the lanthanide rare earth elements (REE) and Pt group elements (PGE) were measured in the Kupferschiefer from the Polish Zechstein Basin at, and in proximity to, the Rote Fäule near the Lubin Mining District. The Rote Fäule is a zone of post-depositional oxidation characterized by the presence of extensive amounts of Fe(III) oxides replacing syn-sedimentary framboidal pyrite. Outward from the Rote Fäule, the remainder of the Kupferschiefer is composed of Cu- and Pb/Zn-mineralized shale surrounding the Rote Fäule and a non-mineralized pyritic black shale in the central basin.The leading hypothesis explaining the high concentrations of PGE, and REE in the Kupferschiefer states that PGE, REE and the associated base metals were mobilized by oxidizing Cl⁻ brines which migrated outward from the Rote Fäule into the reduced Kupferschiefer. According to available thermodynamic data, PGE were in all likelihood present as chloro-complexes in these oxidizing brines, as geologically realistic concentrations of Pt, Pd and Au could be transported as chloro-complexes. The Eh of these brines decreased as they migrated further from the Rote Fäule and into the Kupferschiefer. Base metals and PGE were precipitated in the order of their decreased solubility in these brines. As a result, the concentrations of least soluble PGE (Pt) are highest in the Rote Fäule and in the transition zone adjacent to the Rote Fäule (e.g. [Pt]=202–537 ppb) while the concentrations of the more soluble metals in these brines (Ag, Cu, Pb, and Re) are highest in the reduced-mineralized Kupferschiefer. The sources of the PGE and REE are enigmatic. It is likely that the metals were derived either from the underlying Rotliegendes sandstones and volcanics, the Variscan basement rocks, or the Kupferschiefer shale whose metals were mobilized by saline, oxidizing fluids released during intra-continental rifting in the Triassic period.     

Geology,mineralogy, geochemistry and δ34S of sedimentary rock-hosted Au deposits in Song Hien structure,NE Vietnam

The Song Hien rift basin is considered to be one of the most important regions of gold mineralisation in North East Vietnam. A number of gold deposits in the Song Hien rift basin are hosted in Triassic and Devonian sedimentary formations of the basin. The largest among them are the Bo Va, Tham Riem and Khung Khoang deposits. The Bo Va deposit is hosted in carbonaceous sedimentary rocks of Triassic age, whereas the Tham Riem and Khung Khoang deposits are hosted in carbonaceous sedimentary rocks of Devonian ages. Based on the mineral composition of the ores, the deposits can be divided into to two types: (i) pyrite dominated and (ii) pyrite-arsenopyrite dominated. The Khung Khoang is of the first type and the Bo Va and Tham Riem deposits belong to the second type. The isotopic composition of pyrite and arsenopyrite in the Tham Riem deposit however, is close to that for the ores of the Bo Va deposit. The δ³⁴S value for pyrite ranging from −3.7‰ to −7.4‰ and for arsenopyrite ranging from −3.2‰ to 7.4‰. The δ³⁴S of pyrite in the ore from the Khung Khoang deposit however, has a much heavier isotopic composition of +18.9 to +20.2‰. A narrow range of the variation of sulfur isotopic composition of pyrite and arsenopyrite, the presence of visible gold as inclusions, the presence of chalcopyrite, sphalerite and other inclusions in arsenopyrite and pyrite, the large size of the grains of major ore minerals allow us to assume that the primary gold ores of the Bo Va and Tham Riem deposits underwent metamorphic transformations. The absence of arsenic, antimony, mercury and other characteristic elements in the ores of the Khung Khoang deposit, and substantially heavier isotopic composition of sulfur similar to the sulfur isotopic composition of marine sulfates in the Devonian, allow us to assume another source of the ore components, not connected with the Triassic sedimentary rocks of the Song Hien rift.     

Abnormally High δ34S Values of Edifices at the Mid-Atlantic Ridge: The Closed System Effect at the Sulfide Generation Zone

Doklady Earth Sciences - The S isotope composition of single sulfide grains was studied taking into account the sequence of their formation in samples from the sulfide structures of hydrothermal...     

Reconstruction of palaeohydrological conditions in a lagoon during the 2nd Zechstein cycle through simultaneous use of δD values of individual n-alkanes and δ<Superscript>18</Superscript>O and δ<Superscript>13</Superscript>C values of carbonates

For the first time ¹⁸O and ¹³C values from carbonates and D values of individual n-alkanes were used to reconstruct palaeohydrological conditions in a lagoon at the southern margin of the Central European Zechstein Basin (CEZB). A 12-m core covering the complete Ca2 interval and adjacent anhydrites (A1 and A2) was analyzed for ¹⁸O and ¹³C values of dolomitized carbonates and D values of individual n-alkanes. ¹⁸O_carb values (+2 to +5 vs. VPDB) were strongly influenced by evaporation and temporal freshwater input into the lagoon. The ¹³C_carb values (–1 to +4 vs. VPDB) were controlled mainly by changes in primary production. Both isotopic ratios show an inverse relationship throughout most of the core, contradicting diagenetic alteration, since ¹³C_carb values are not altered significantly during dolomitization. Assuming a temperature range of 35–40 °C in the lagoon, ¹⁸O_carb values of +2.5 to +8 (vs. VSMOW) for the lagoonal water can be reconstructed. The lagoon may have desiccated twice during the Ca2 interval, as indicated by very high ¹⁸O_carb and low ¹³C_carb values, coinciding with increasing amount of anhydrite in the analyzed sample. These events seem to reflect not just local but a regional intra-Ca2 cyclicity. Measured D values of the short-chain n-alkanes, namely n-C₁₆ and n-C₁₈ which are widely used as indicators for photosynthetic bacterial and algal input, reflect the isotopic composition of the lagoonal water. Assuming constant fractionation during incorporation of hydrogen into lipids of –160, an average D value of +70 (vs. VSMOW) can be reconstructed for the lagoonal water, accounting for very arid conditions. The long-chain n-alkanes n-C₂₇, n-C₂₈, n-C₂₉ and n-C₃₀, thought to be derived from the leaf waxes of terrestrial higher plants, were shown to be depleted in D relative to the short-chain alkanes, therefore indicating a different hydrogen source. Terrestrial plants in arid areas mainly use water supplied by precipitation. By using a smaller fractionation of –120 due to evaporation processes in the leaves, reconstructed values vary between –74 and –9 (vs. VSMOW). These values are not indicating extremely arid conditions, implying that the long-chain n-alkanes were transported trough wind and/or rivers into the lagoon at the Zechstein Sea coast. D_water values, reconstructed using the n-C₁₆ alkane and ¹⁸O _water values, independently reconstructed on the same sample using the temperature dependant fractionation for dolomites are good agreement and suggest high amounts of evaporation affecting the coastal lagoon. Altogether, our results indicate that hydrogen isotopic ratios of n-alkanes give information on their origin and are a useful proxy for palaeoclimatic reconstruction.     

Distribution of δ~(34)S and δ~(18)O in SO_4~(2-) in Groundwater from the Ordos Cretaceous Groundwater Basin and Geological Implications

<正>The Ordos Cretaceous Groundwater Basin,located in an arid-semiarid area in northwestern China,is a large-style groundwater basin.SO_4~(2-) is one of the major harmful components in groundwater.Dissolved SO_4~(2-) concentrations,andδ~(34)S-SO_4~(2-) andδ~(18)O-SO_4~(2-) in groundwater from 14 boreholes and in gypsum from aquifer were analyzed.Results show that SO_4~(2-) in shallow groundwaters originates from precipitation,sulfide oxidation,and dissolution of stratum sulphate,with a big range ofδ~(34)S values,from-10.7‰to 9.2‰,and addition of SO_4~(2-) in deep groundwater results from dissolution of stratum sulphate,with biggerδ~(34)S values,from 7.8‰to 18.5‰,compared with those in shallow groundwater.This research also indicates that three types of sulphate are present in the strata,and characterized by highδ~(34)S values and highδ~(18)O values-style,highδ~(34)S values and middleδ~(18)O valuesstyle, middleδ~(34)S values and lowδ~(18)O values-style,respectively.Theδ~(34)S-SO_4~(2-) andδ~(18)O-SO_4~(2-) in groundwater have a good perspective for application in distinguishing different groundwater systems and determining groundwater circulation and evolution in this area.