Journal: Journal of Geochemical Exploration

Abbreviation

J. geochem. explor.

Publisher

Elsevier

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ISSN

0375-6742
1879-1689

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Publications 1 - 10 of 14
  • Trace element geochemistry of sphalerite and chalcopyrite in arc-hosted VMS deposits
    Item type: Journal Article
    Torró, Lisard; Benites, Diego; Vallance, Jean; et al. (2022)
    Journal of Geochemical Exploration
    Trace element compositions of sphalerite and chalcopyrite have been investigated for four arc-hosted Cretaceous VMS deposits (María Teresa, Perubar, and Palma in Peru, and Cerro de Maimón in the Dominican Republic) using laser ablation inductively-coupled plasma mass spectrometry. In sphalerite, Fe, Mn, Cd, Hg, Ag, Sb, Se, In, Ge, and Ga are lattice-bound, whereas Sn, Tl, Bi, and Pb occur at least partly as mineral microinclusions. Significant variations in the contents of minor and trace elements are observed in sphalerite grains from individual deposits. A strong negative correlation between Fe (Inter-Quartile Range [IQR] 44,009–18,168 ppm) and Zn indicates a dominant Fe2+ ↔ Zn2+ simple isovalent substitution. Regarding potential high-tech by-products, the contents of In (IQR 42–1.6 ppm, up to 415 ppm) and Ga (IQR 31–5.9 ppm, up to 96 ppm) in the studied sphalerite are normally much higher than those of Ge (IQR 0.85–0.16 ppm, up to 9.3 ppm). Correlation trends suggest Cu+ + In3+ ↔ 2Zn2+, Cu+ + Ga3+ ↔ 2Zn2+, and more complex substitution mechanisms of Zn involving combinations of monovalent (Cu+, Ag+), divalent (Ge2+?), trivalent (In3+, Ga3+, [Sn3+?]), and quadrivalent (Ge4+, Sn4+) cations. As for chalcopyrite, Zn, Ag, Sn, Cd, Se, In, Ga, and Ge are interpreted to be lattice-bound, whereas Mo, Au, Tl, Sb, Pb, and Bi probably occur as microinclusions. Relative to sphalerite, chalcopyrite is depleted in In (IQR 28–8.4 ppm, up to 49 ppm) and Ga (IQR 8.3–2.9 ppm, up to 24 ppm) and enriched in Ge (IQR 5.9–0.70 ppm, up to 80 ppm). Of the other trace elements, Zn (IQR 426–190 ppm) is the most highly concentrated in the studied chalcopyrite, followed by Ag (IQR 136–23 ppm), Se (IQR 64–22 ppm), Sn (IQR 53–1.3 ppm), and Cd (IQR 12–6.0 ppm). General positive correlation trends between Zn, Cd, In, Ge, and Ga in chalcopyrite suggest varied coupled substitution mechanisms of Fe and Cu with fluctuating valences due to covalent bonding. Trace-element distribution patterns in sphalerite and chalcopyrite were studied for the zone-refined Sofía-D massive sulfide body in the María Teresa deposit, which comprises a lower lower portion of dominant pyrite sheathed upward by zones of chalcopyrite (Cu zone), sphalerite (Zn zone) and galena + sphalerite ± fahlore ± barite (Pb – Zn – Ag zone). Bottom to top of the sulfide body, sphalerite records progressive depletion in In, Cu, Mn, and Se, and enrichment in Ge. This distribution pattern agrees with increasing crystallization temperatures and/or volatile magmatic influx towards the lower portion of the massive mineralization. Distribution of trace elements in chalcopyrite is rather uneven except for a sustained enrichment in Se towards the basal portion of the sulfide body. The fact that such trends are preserved in spite of extensive recrystallization during thermal metamorphism in parts of the Sofía-D massive sulfide mineralization suggests i) a closed metamorphic system and ii) that element interdiffusion was prominently local. Accordingly, we propose that sphalerite lattice-bound trace elements distribution patterns described in this article can help determine the polarity of massive sulfide bodies in VMS districts in metamorphosed and tectonized terranes. © 2021 Elsevier B.V. All rights reserved
  • Sources and occurrence of trace elements in water and sediments of Darbandikhan reservoir in Iraqi Kurdistan: A human health and ecological risk assessment
    Item type: Journal Article
    Hawrami, Karzan; Baset, Abdolbaset; Ibrahim, Kocher; et al. (2025)
    Journal of Geochemical Exploration
    Freshwater pollution is a global threat, contributing to the decline in biodiversity whilst making water unsafe for human consumption. Climate change may further aggravate water scarcity and quality. Iraq is ranked as highly vulnerable to climate change and predicted to be extremely water stressed by 2040. Iraqi population relies on surface water, yet its availability and quality face several challenges. This study reports on Darbandikhan, a major water reservoir in Iraqi Kurdistan. The occurrence, spatial/vertical distribution and associations of 50+ elements in sediments, surface and deep water in 48 sites shed light on contamination patterns and enabled identification of several geogenic and anthropogenic sources, and locally enriched areas where mitigation actions are recommended. Darbandikhan sediments revealed a distinctive geogenic signature reflecting the Zagros geological setting. The presence of mafic/ultramafic rocks and mineralisations in the catchment resulted in high levels of As, Cr and Ni in sediments, whilst no anthropogenic sources could be unequivocally discriminated. Elemental associations with a geogenic signature and higher concentrations in deep water suggested that bottom sediments act as a secondary source of potentially toxic elements into the overlying water column. By contrast, surface water composition was primarily controlled by fresh inputs from several streams draining into the reservoir. Local enrichments in As, Ba, Mo, Ni, Sb, V and Zn were traced back to specific anthropogenic discharges. Assessment of the contamination status with several indices suggested mild to moderate environmental risk and low health risk in the majority of sites, although caution in water consumption is advised.
  • Zinc-enriched and zinc-biofortified feed as a possible animal remedy in pastoral agriculture
    Item type: Journal Article
    Anderson, Christopher W.N.; Robinson, Brett H.; West, David M.; et al. (2012)
    Journal of Geochemical Exploration
  • An attempt to use LA-ICP-SMS to quantify enrichment of trace elements on pyrite surfaces in oxidizing mine tailings
    Item type: Journal Article
    Öhlander, Björn; Müller, Barbara; Axelsson, Mikael; et al. (2007)
    Journal of Geochemical Exploration
  • Distribution and behavior of arsenic in soils and waters in the vicinity of the former gold-arsenic mine of Salanfe, Western Switzerland
    Item type: Journal Article
    Pfeifer, Hans-Rudolf; Häussermann, Anne; Lavanchy, Jean-Claude; et al. (2007)
    Journal of Geochemical Exploration
  • Multi-reservoir fluid mixing processes in rift-related hydrothermal veins, Schwarzwald, SW-Germany
    Item type: Journal Article
    Walter, Benjamin F.; Burisch, Mathias; Fusswinkel, Tobias; et al. (2018)
    Journal of Geochemical Exploration
  • LA-ICP-MS analysis of single fluid inclusions in a quartz crystal (Madan ore district, Bulgaria)
    Item type: Journal Article
    Kotzeva, Boriana G.; Guillong, Marcel; Stefanova, Elitsa; et al. (2011)
    Journal of Geochemical Exploration
  • Seasonal change of microbial activity in microbially aided bioremediation
    Item type: Journal Article
    Schindler, Frank; Merbold, Lutz; Karlsson, Stefan; et al. (2017)
    Journal of Geochemical Exploration
  • Formation of hydrothermal fluorite-hematite veins by mixing of continental basement brine and redbed-derived fluid: Schwarzwald mining district, SW-Germany
    Item type: Journal Article
    Walter, Benjamin F.; Jensen, Jordan L.; Coutinho, Paulo; et al. (2020)
    Journal of Geochemical Exploration
  • Classification of wheat genotypes by yield and densities of grain zinc and iron using cluster analysis
    Item type: Journal Article
    Khoshgoftarmanesh, Amir H.; Sharifi, H. R.; Afiuni, B.; et al. (2012)
    Journal of Geochemical Exploration
Publications 1 - 10 of 14