scholarly journals Pyrite Textures, Trace Elements and Sulfur Isotope Chemistry of Bijaigarh Shales, Vindhyan Basin, India and Their Implications

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 588
Author(s):  
Indrani Mukherjee ◽  
Mihir Deb ◽  
Ross R. Large ◽  
Jacqueline Halpin ◽  
Sebastien Meffre ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Sulfur Isotope ◽  
Volcanic Rocks ◽  
Central India ◽  
High Energy ◽  
Vindhyan Basin ◽  
Mean Values ◽  
Fine Grained ◽  
Sedimentary Pyrite

The Vindhyan Basin in central India preserves a thick (~5 km) sequence of sedimentary and lesser volcanic rocks that provide a valuable archive of a part of the Proterozoic (~1800–900 Ma) in India. Here, we present an analysis of key sedimentary pyrite textures and their trace element and sulfur isotope compositions in the Bijaigarh Shale (1210 ± 52 Ma) in the Vindhyan Supergroup, using reflected light microscopy, LA-ICP-MS and SHRIMP-SI, respectively. A variety of sedimentary pyrite textures (fine-grained disseminated to aggregates, framboids, lags, and possibly microbial pyrite textures) are observed reflecting quiet and strongly anoxic water column conditions punctuated by occasional high-energy events (storm incursions). Key redox sensitive or sensitive to oxidative weathering trace elements (Co, Ni, Zn, Mo, Se) and ratios of (Se/Co, Mo/Co, Zn/Co) measured in sedimentary pyrites from the Bijaigarh Shale are used to infer atmospheric redox conditions during its deposition. Most trace elements are depleted relative to Proterozoic mean values. Sulfur isotope compositions of pyrite, measured using SHRIMP-SI, show an increase in δ34S as we move up stratigraphy with positive δ34S values ranging from 5.9‰ (lower) to 26.08‰ (upper). We propose limited sulphate supply caused the pyrites to incorporate the heavier isotope. Overall, we interpret these low trace element signatures and heavy sulfur isotope compositions to indicate relatively suppressed oxidative weathering on land during the deposition of the Bijaigarh Shale.

The Witwatersrand pyrites and metamorphism

1983 ◽  
Vol 47 (345) ◽  
pp. 473-479 ◽  
Author(s):  
D. K. Hallbauer ◽  
K. von Gehlen
Keyword(s):  
Trace Element ◽  
Fluid Inclusions ◽  
Depositional Environment ◽  
Volcanic Rocks ◽  
Source Rocks ◽  
Fine Grained ◽  
Mineral Inclusions ◽  
Ore Minerals ◽  
Hand Specimen

AbstractEvidence obtained from morphological and extensive trace element studies, and from the examination of mineral and fluid inclusions in Witwatersrand pyrites, shows three major types of pyrite: (i) detrital pyrite (rounded pyrite crystals transported into the depositional environment); (ii) synsedimentary pyrite (round and rounded aggregates of fine-grained pyrite formed within the depositional environmen); and (iii) authigenic pyrite (newly crystallized and/or recrystallized pyrite formed after deposition). The detrital grains contain mineral inclusions such as biotite, feldspar, apatite, zircon, sphene, and various ore minerals, and fluid inclusions with daughter minerals. Most of the inclusions are incompatible with an origin by sulphidization. Recrystallized authigenic pyrite occurs in large quantities but only in horizons or localities which have been subjected to higher temperatures during the intrusion or extrusion of younger volcanic rocks. Important additional findings are the often substantial amounts of pyrite and small amounts of particles of gold found in Archaean granites (Hallbauer, 1982) as possible source rocks for the Witwatersrand detritus. Large differences in Ag and Hg content between homogeneous single gold grains within a hand specimen indicate a lack of metamorphic homogenization. The influence of metamorphism on the Witwatersrand pyrites can therefore be described as only slight and generally negligible.

scholarly journals The formation mechanisms of sedimentary pyrite nodules determined by trace element and sulfur isotope microanalysis

2019 ◽  
Vol 259 ◽  
pp. 53-68 ◽  
Author(s):  
Daniel Gregory ◽  
Indrani Mukherjee ◽  
Stephanie L. Olson ◽  
Ross R. Large ◽  
Leonid V. Danyushevsky ◽  
...  
Keyword(s):  
Trace Element ◽  
Sulfur Isotope ◽  
Formation Mechanisms ◽  
Sedimentary Pyrite

Pyrite trace-element and sulfur isotope geochemistry of paleo-mesoproterozoic McArthur Basin: Proxy for oxidative weathering

2019 ◽  
Vol 104 (9) ◽  
pp. 1256-1272 ◽  
Author(s):  
Indrani Mukherjee ◽  
Ross R. Large ◽  
Stuart Bull ◽  
Daniel G. Gregory ◽  
Aleksandr S. Stepanov ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Sulfur Isotope ◽  
Gradual Increase ◽  
Isotope Geochemistry ◽  
Atmospheric Oxygen ◽  
Black Shales ◽  
Elemental Ratios ◽  
System A ◽  
Icp Ms

Abstract Redox-sensitive trace elements and sulfur isotope compositions obtained via in situ analyses of sedimentary pyrites from marine black shales are used to track atmosphere-ocean redox conditions between ∼1730 and ∼1360 Ma in the McArthur Basin, northern Australia. Three black shale formations within the basin (Wollogorang Formation 1730 ± 3 Ma, Barney Creek Formation 1640 ± 3 Ma, and Upper Velkerri Formation 1361 ± 21 Ma) display systematic stratigraphic variations in pyrite trace-element compositions obtained using LA-ICP-MS. The concentrations of several trace elements and their ratios, such as Se, Zn, Se/Co, Ni/Co, Zn/Co, Mo/Co, Se/Bi, Zn/Bi, Ni/Bi, increase from the stratigraphically lower Wollogorang Formation to the Upper Velkerri Formation. Cobalt, Bi, Mo, Cu, and Tl show a consistent decrease in abundance while Ni, As, and Pb show no obvious trends. We interpret these trace element trends as a response to the gradual increase of oxygen in the atmosphere-ocean system from ∼1730 to 1360 Ma. Elements more mobile during erosion under rising atmospheric oxygen show an increase up stratigraphy (e.g., Zn, Se), whereas elements that are less mobile show a decrease (e.g., Co, Bi). We also propose the increase of elemental ratios (Se/Co, Ni/Co, Zn/Co, Mo/Co, Ni/Bi, and Zn/Bi) up stratigraphy are strong indicators of atmospheric oxygenation. Sulfur isotopic compositions of marine pyrite (δ34Spyrite) from these formations, obtained using SHRIMP-SI, are highly variable, with the Wollogorang Formation exhibiting less variation (δ34S = –29.4 to +9.5‰; mean –5.03‰) in comparison to the Barney Creek (δ34S = –13.8 to +41.8‰; mean +19.88‰) and Velkerri Formations (δ34S = –14.2 to +52.8‰; mean +26.9‰). We propose that the shift in mean δ34S to heavier values up-section corresponds to increasing deep water oxygenation from ∼1730 to 1360 Ma. Incursion of oxygenated waters possibly caused a decrease in the areal extent of anoxic areas, at the same time, creating a possibly efficient reducing system. A stronger reducing system caused the δ34S of the sedimentary pyrites to become progressively heavier. Interestingly, heavy δ34S in pyrites overlaps with the increase in the concentration of certain trace elements (and their ratios) in sedimentary pyrites (Se, Zn, Se/Co, Ni/Co, Zn/Co, Mo/Co, Ni/Bi, and Zn/Bi). This study concludes that there was a gradual increase of atmospheric oxygen accompanied by ocean oxygenation through the first ∼400 million years of the Boring Billion (1800–1400 Ma) in the McArthur Basin.

Immobile trace elements and Archean volcanic stratigraphy in the Timmins mining area, Ontario

1979 ◽  
Vol 16 (2) ◽  
pp. 305-311 ◽  
Author(s):  
J. F. Davies ◽  
R. W. E. Grant ◽  
R. E. S. Whitehead
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
No Value ◽  
Volcanic Rocks ◽  
Mining Area ◽  
Stratigraphic Correlation ◽  
Trace Element Data ◽  
Volcanic Stratigraphy ◽  
Lithostratigraphic Units ◽  
Hydrolysis Of

Carbonate alteration and hydrolysis of mafic volcanic rocks in the Timmins area have been accompanied by mobilization and redistribution of alkalies, CaO, MgO, and FeO. These major oxides are of dubious value in classifying the volcanic rocks, and are of no value in identifying and correlating lithostratigraphic units. The trace elements Y, Zr, TiO2, and Cr, whose fractionation tendencies parallel those of the alkalies, FeO and MgO, are relatively immobile and display characteristic patterns within different volcanic units. The trace-element patterns are highly diagnostic, and their distribution corresponds to the distribution of lithostratigraphic units. Immobile trace-element data represent a potentially valuable tool in stratigraphic correlation of Archean volcanic rocks, whether altered or unaltered.

scholarly journals Are serum levels of trace elements in children with auditory neuropathy within normal limits? – A pilot study

2010 ◽  
Vol 33 (3) ◽  
pp. 155
Author(s):  
Nuray Bayar Muluk ◽  
Fulya Yalçınkaya ◽  
Osman Kürşat Arikan ◽  
Özden Çırpar ◽  
Sedat Kaygusuz ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Serum Levels ◽  
Auditory Neuropathy ◽  
Neural Function ◽  
Mean Values ◽  
Normal Limits ◽  
High Zinc ◽  
Serum Trace Element ◽  
Trace Element Levels

Objectives: To determine whether trace elements that are essential for neural function play a role in the pathophsiology and etiology of auditory neuropathy (AN).. Materials and methods: Patients diagnosed with auditory neuropathy consisted of eight children (two male, six female). The blood tests including the measurement of sodium, potassium, chloride, calcium, phosphorus, iron, copper and magnesium were done in children with AN during their routine care. Results: Of the eight children with AN, many had serum levels outside the normal range: one had low sodium, two had low potassium, one had low chloride, two had high zinc and three had low zinc, two had low calcium and two had higher than normal phosphorus. Conclusion: Although some serum trace element levels in our patients were higher or lower than normal values, the mean values were within normal limits. Thus, we were unable to detect a relationship between serum trace element levels and AN-. In the future, larger studies should be conducted to confirm these findings.

scholarly journals Target hazard quotient evaluation of selected trace elements in highly consumed crustacean species in Lagos, Nigeria

2021 ◽  
Vol 43 ◽  
pp. e53052
Author(s):  
Rasheed Olatunji Moruf
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Hazard Quotient ◽  
Daily Intake ◽  
Hazard Index ◽  
Target Hazard Quotient ◽  
Mean Values ◽  
Mantis Shrimp ◽  
Muscle Tissues ◽  
The Mean

Crustaceans are known for their trace element bioaccumulation abilities. Muscle tissues of lagoon crab, marine crab, pink shrimp and mantis shrimp marketed for consumption in Nigeria were analyzed for Mn, Fe, Cu, Zn, Hg and Cr levels using standard methods. Muscle levels in mg kg-1 of Mn (0.03±0.00 in lagoon crab), Fe (0.072±0.01 in mantis shrimp), Cu (0.344±0.01 in lagoon crab) and Zn (0.073±0.00 in mantis shrimp) were significantly different (p<0.05) from their corresponding values in other examined crustaceans. The mean values of Cr and Hg were not significantly different across samples. The estimated daily intake of trace element (mg person-1day-1) revealed that Hg (0.000001) in marine crab contributed the lowest daily intake while Zn (0.000226) in lagoon crab contributed the highest daily intake. Total hazard quotient (THQ) values for the trace elements followed descending order of Hg > Cu > Zn > Fe > Mn > Cr. Lagoon crab showed the highest total hazard index among the organisms with 44.80 %, while the least was observed in mantis shrimp with 13.30 %. It is concluded that, as far as human health is concerned, the mean elemental levels in the muscle tissues of the organisms examined pose no danger (THQ < 1).

Mineralogical composition of and trace-element accumulation in lower Toarcian anoxic sediments: a case study from the Bilong Co. oil shale, eastern Tethys

2015 ◽  
Vol 153 (4) ◽  
pp. 618-634 ◽  
Author(s):  
XIUGEN FU ◽  
JIAN WANG ◽  
XINGLEI FENG ◽  
WENBIN CHEN ◽  
DONG WANG ◽  
...  
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Oil Shale ◽  
Volcanic Rocks ◽  
Mineralogical Composition ◽  
Geochemical Data ◽  
Anoxic Sediments ◽  
Marine Influence ◽  
High Concentrations ◽  
Element Enrichment

AbstractThe sediments of organic-rich oil shales in the Bilong Co. area can be correlated with those of the early Toarcian anoxic black-shale events in Europe. The Bilong Co. sediments are rich in trace elements Se, Mo, Cd, As and Ni, and, to a lesser extent, Li, F, V, Co, Cu, Cs, Hg and Bi, in comparison to the upper continental crust. Thirty-two oil shale samples were collected from the Bilong Co. oil shale to evaluate the controlling factors of trace-element enrichment in the lower Toarcian anoxic sediments. Minerals identified in the Bilong Co. oil shale include calcite, quartz, illite, feldspar and dolomite, and trace amounts of siderite, magnesite, halite, haematite, zeolite, amphibole, gypsum, anhydrite, apatite, pyrite, sphalerite, barite and mixed-layer illite/smectite. Mineralogical and geochemical data show that seawater and hydrothermal activities are the dominant influences on the mineralogical composition and elevated trace-element concentrations in the oil shale. The clay minerals, quartz and feldspar in the Bilong Co. oil shale were derived from the Nadi Kangri volcanic rocks. Input of sediment from this source may have led to enrichment of trace elements Li, Cr and Cs in the oil shale. Carbonate minerals and nodular- and framboidal-pyrite are authigenic phases formed from seawater. The enrichment of V, Co, Ni, Cu, Mo, As, Se, Bi and U in the oil shale was owing to marine influence. Barite, sphalerite and fracture-filling pyrites were derived from hydrothermal solutions. High concentrations of F, Zn and Cd were probably derived from hydrothermal fluids.

Tectono-magmatic Interplay and Related Metasomatism in Gabbros of the Chenaillet Ophiolite (Western Alps)

2019 ◽  
Vol 60 (12) ◽  
pp. 2483-2508 ◽  
Author(s):  
R Tribuzio ◽  
G Manatschal ◽  
M R Renna ◽  
L Ottolini ◽  
A Zanetti
Keyword(s):  
Trace Elements ◽  
Trace Element ◽  
Western Alps ◽  
Fine Grained ◽  
Ductile Shearing ◽  
Trace Element Signature ◽  
High Concentrations ◽  
Incompatible Trace Elements ◽  
Detachment Faulting ◽  
Ocean Ridge

Abstract The Jurassic Chenaillet ophiolite in the Western Alps consists of a gabbro–mantle association exhumed to the seafloor through detachment faulting and partly covered by basaltic lavas. One of the Chenaillet gabbroic bodies includes mylonites that are transected by a network of felsic veins, thereby testifying to the interplay of ductile shearing and magma emplacement. The deformed gabbros preserve clinopyroxene porphyroclasts of primary magmatic origin, which are typically mantled by amphibole (titanian edenite) and minor secondary clinopyroxene. Titanian edenite and secondary clinopyroxene also occur as fine-grained syn-kinematic phases locally associated with fine-grained plagioclase. The felsic veins are made up of anorthite-poor plagioclase and minor titanian edenite. Geothermometric investigations document that the ductile gabbro deformation and the crystallization of the felsic veins occurred at 765 ± 50 °C and 800 ± 55 °C, respectively. With respect to undeformed counterparts, the deformed gabbros are variably enriched in SiO2 and variably depleted in Mg/(Mg + Fetot2+) and Ca/(Ca + Na). In addition, the deformed gabbros show relatively high concentrations of incompatible trace elements such as rare earth elements (REE), Y, Zr and Nb. The felsic veins are characterized by low Mg/(Mg + Fetot2+) and Ca/(Ca + Na), high SiO2 and high concentrations of incompatible trace elements. Relict clinopyroxene porphyroclasts from the deformed gabbros display a rather primitive, mid-ocean ridge-type geochemical signature, which contrasts with the trace element fingerprint of titanian edenite from both the deformed gabbros and the felsic veins. For instance, titanian edenite typically has relatively high REE abundances, with chondrite-normalized REE patterns characterized by a pronounced negative Eu anomaly. A similar trace element signature is shown by secondary clinopyroxene from the deformed gabbros. Amphibole from both the deformed gabbros and the felsic veins displays high F/Cl values. We show that the SiO2-rich hydrous melts feeding the felsic veins were involved in the high-temperature gabbro deformation and that melt–gabbro reactions led to major and trace element metasomatism of the deforming gabbros.

scholarly journals Trace Element Analysis of Bovine Liver: Interlaboratory Survey in Australia and New Zealand

1980 ◽  
Vol 63 (4) ◽  
pp. 809-813 ◽  
Author(s):  
T S Koh ◽  
T H Benson ◽  
G J Judson
Keyword(s):  
Trace Elements ◽  
New Zealand ◽  
Trace Element ◽  
Trace Element Analysis ◽  
Bovine Liver ◽  
Moisture Determination ◽  
Element Analysis ◽  
Mean Values ◽  
Coefficients Of Variation

Abstract An interlaboratory survey of the determination of trace elements in bovine liver was undertaken. Thirty-three laboratories from Australia and 15 from New Zealand returned results. Moisture determination results were variable despite the use of a recommended drying procedure. For the 10 trace elements determined, the mean values (μg/g) with their interlaboratory coefficients of variation (CV) were: cadmium, 1.2 (42.5%); cobalt, 0.21 (9.5%); copper, 110 (6.0%); iron, 276 (11.0%); lead, 0.6 (48.9%); manganese, 8.6 (13.9%); mercury, 0.03 (30.0%); molybdenum, 2.5 (45.6%); selenium, 1.0 (17.5%); zinc, 219 (8.2%). The intralaboratory CV for determining each of these elements was less than 9% except for the lead CV which was 20.2%. Results for the determination of sodium, potassium, calcium, and magnesium were also reported. The survey shows that while the use of a standard reference material can improve the performance of laboratories in trace element analysis, it may also introduce analytical bias.

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