Evidence from sulfur isotope and trace elements in pyrites for their multiple post-depositional processes in uranium ores at the Stanleigh Mine, Elliot Lake, Ontario, Canada

2006 ◽  
Author(s):  
Kosei E. Yamaguchi ◽  
Hiroshi Ohmoto
Keyword(s):  
Trace Elements ◽  
Sulfur Isotope ◽  
Lake Ontario ◽  
Depositional Processes

Fluid evolution and gold precipitation in the Muping gold deposit (Jiaodong, China): Insights from in-situ trace elements and sulfur isotope of sulfides

2020 ◽  
Vol 218 ◽  
pp. 106617
Author(s):  
Yong-Wen Zhang ◽  
Fang-Fang Hu ◽  
Hong-Rui Fan ◽  
Xuan Liu ◽  
Kai Feng ◽  
...  
Keyword(s):  
Trace Elements ◽  
Gold Deposit ◽  
Sulfur Isotope ◽  
Fluid Evolution

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.

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.

In situ trace elements and sulfur isotope analysis of sulfides from the Akiri cu ± (ag) deposit, Benue trough, north-Central Nigeria: Implications for ore genesis

Geochemistry ◽  
2021 ◽  
pp. 125801
Author(s):  
Victor Ikechukwu Vincent ◽  
Huan Li ◽  
Musa Bala Girei ◽  
Michael W. Förster ◽  
Hafizullah Abba Ahmed ◽  
...  
Keyword(s):  
Trace Elements ◽  
Sulfur Isotope ◽  
Isotope Analysis ◽  
Ore Genesis ◽  
North Central ◽  
Benue Trough
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