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Journal articles on the topic 'Ni-Cu-PGE deposits'

Author: Grafiati

Published: 4 June 2021

Last updated: 6 February 2022

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1

Moilanen, M., E. Hanski, J. Konnunaho, T. Törmänen, S. H. Yang, Y. Lahaye, H. O’Brien, and J. Illikainen. "Composition of iron oxides in Archean and Paleoproterozoic mafic-ultramafic hosted Ni-Cu-PGE deposits in northern Fennoscandia: application to mineral exploration." Mineralium Deposita 55, no. 8 (January 11, 2020): 1515–34. http://dx.doi.org/10.1007/s00126-020-00953-1.

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Abstract Using electron probe microanalyzer (EPMA) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), we analyzed major and trace element compositions of iron oxides from Ni-Cu-PGE sulfide deposits hosted by mafic-ultramafic rocks in northern Fennoscandia, mostly focusing on Finland. The main research targets were the Archean Ruossakero Ni-(Cu) deposit; Tulppio dunite and related Ni-PGE mineralization; Hietaharju, Vaara, and Tainiovaara Ni-(Cu-PGE) deposits; and Paleoproterozoic Lomalampi PGE-(Ni-Cu) deposit. In addition, some reference samples from the Pechenga (Russia), Jinchuan (China), and Kevitsa (Finland) Ni-Cu-PGE sulfide deposits, and a barren komatiite sequence in the Kovero area (Finland) were studied. Magnetite and Cr-magnetite show a wide range of trace element compositions as a result of the variation of silicate and sulfide melt compositions and their post-magmatic modification history. Most importantly, the Ni content in oxide shows a positive correlation with the Ni tenor of the sulfide phase in equilibrium with magnetite, regardless of whether the sulfide assemblage is magmatic or post-magmatic in origin. The massive sulfide samples contain an oxide phase varying in composition from Cr-magnetite to magnetite, indicating that Cr-magnetite can crystallize directly from sulfide liquid. The Mg concentration of magnetites in massive sulfide samples is lowest among the samples analyzed, and this can be regarded as a diagnostic feature of an oxide phase crystallized together with primitive Fe-rich MSS (monosulfide solid solution). Our results show that magnetite geochemistry, plotted in appropriate discrimination diagrams, together with petrographical observations could be used as an indicator of potential Ni-(Cu-PGE) mineralization.

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2

Lu, Yiguan, C. Michael Lesher, and Jun Deng. "Geochemistry and genesis of magmatic Ni-Cu-(PGE) and PGE-(Cu)-(Ni) deposits in China." Ore Geology Reviews 107 (April 2019): 863–87. http://dx.doi.org/10.1016/j.oregeorev.2019.03.024.

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3

Lesher, C. M., and P. C. Lightfoot. "Preface for thematic issue on Ni–Cu–PGE deposits." Mineralium Deposita 47, no. 1-2 (August 5, 2011): 1–2. http://dx.doi.org/10.1007/s00126-011-0379-y.

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4

Makkonen, Hannu V., Tapio Halkoaho, Jukka Konnunaho, Kalevi Rasilainen, Asko Kontinen, and Pasi Eilu. "Ni-(Cu-PGE) deposits in Finland – Geology and exploration potential." Ore Geology Reviews 90 (November 2017): 667–96. http://dx.doi.org/10.1016/j.oregeorev.2017.06.008.

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5

Song, Xieyan. "Magmatic Ni-Cu and PGE Deposits: Geology, Geochemistry, and Genesis." Geoscience Frontiers 3, no. 6 (November 2012): 945. http://dx.doi.org/10.1016/j.gsf.2012.05.002.

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6

Hall, M. F., B. Lafrance, and H. L. Gibson. "Emplacement of sharp-walled sulfide veins during the formation and reactivation of impact-related structures at the Broken Hammer Mine, Sudbury, Ontario." Canadian Journal of Earth Sciences 57, no. 10 (October 2020): 1149–66. http://dx.doi.org/10.1139/cjes-2019-0229.

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Broken Hammer is a hybrid Cu–Ni–Platinum Group Element (PGE) footwall deposit located in Archean basement rocks below the impact-induced Sudbury Igneous Complex (SIC), Canada. The deposit consists of massive chalcopyrite veins surrounded by thin epidote, actinolite, and quartz selvedges and low-sulfide, high-PGE mineralization consisting of disseminated chalcopyrite (<5%) and platinum group minerals, associated with Ni-bearing chlorite overprinting alteration patches of epidote, actinolite, and quartz. The veins are grouped into five steeply-dipping sets, striking northeast-, southwest-, southeast-, south-, and east–west, which were emplaced along impact-related fractures that were reactivated multiple times during stabilization of the crater floor. Early reactivation of the fractures created pathways for the migration of hydrothermal fluids from which quartz and chlorite precipitated sealing the fractures. Renewed slip shattered the quartz–chlorite veins into fragments that were incorporated in massive sulfide veins that crystallized from fractionated sulfide melts or from high temperature (400–500 °C) hydrothermal fluids, which migrated outward into the basement rocks from a cooling and crystallizing SIC melt sheet. Hydrothermal fluids syn-genetic with the epidote–actinolite–quartz alteration distributed the PGE into the footwall rocks, or late hydrothermal fluids associated with the Ni-bearing chlorite leached Ni and PGMs from the sulfide veins and redistributed them to form low-sulfide, high-PGE zones in the footwall rocks. During post-impact tectonic events, slip at temperatures below the brittle–ductile transition for chalcopyrite (<200 °C to 250 °C) produced striations along the vein margins. The Broken Hammer deposit exemplifies how Cu–Ni–PGE footwall deposits formed by the reactivation of impact-related fractures that provided conduits for the migration of melts and hydrothermal fluids.

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7

Sluzhenikin, Sergey F., and Andrey V. Mokhov. "Gold and silver in PGE–Cu–Ni and PGE ores of the Noril’sk deposits, Russia." Mineralium Deposita 50, no. 4 (August 19, 2014): 465–92. http://dx.doi.org/10.1007/s00126-014-0543-2.

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8

Duran, Charley J., Sarah-Jane Barnes, Eduardo T. Mansur, Sarah A. S. Dare, L. Paul Bédard, and Sergey F. Sluzhenikin. "Magnetite Chemistry by LA-ICP-MS Records Sulfide Fractional Crystallization in Massive Nickel-Copper-Platinum Group Element Ores from the Norilsk-Talnakh Mining District (Siberia, Russia): Implications for Trace Element Partitioning into Magnetite." Economic Geology 115, no. 6 (September 1, 2020): 1245–66. http://dx.doi.org/10.5382/econgeo.4742.

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Abstract Mineralogical and chemical zonations observed in massive sulfide ores from Ni-Cu-platinum group element (PGE) deposits are commonly ascribed to the fractional crystallization of monosulfide solid solution (MSS) and intermediate solid solution (ISS) from sulfide liquid. Recent studies of classic examples of zoned orebodies at Sudbury and Voisey’s Bay (Canada) demonstrated that the chemistry of magnetite crystallized from sulfide liquid was varying in response to sulfide fractional crystallization. Other classic examples of zoned Ni-Cu-PGE sulfide deposits occur in the Norilsk-Talnakh mining district (Russia), yet magnetite in these orebodies has received little attention. In this contribution, we document the chemistry of magnetite in samples from Norilsk-Talnakh, spanning the classic range of sulfide composition, from Cu poor (MSS) to Cu rich (ISS). Based on textural features and mineral associations, four types of magnetite with distinct chemical composition are identified: (1) MSS magnetite, (2) ISS magnetite, (3) reactional magnetite (at the sulfide-silicate interface), and (4) hydrothermal magnetite (resulting from sulfide-fluid interaction). Compositional variability in lithophile and chalcophile elements records sulfide fractional crystallization across MSS and ISS magnetites and sulfide interaction with silicate minerals (reactional magnetite) and fluids (hydrothermal magnetite). Estimated partition coefficients for magnetite in sulfide systems are unlike those in silicate systems. In sulfide systems, all lithophile elements are compatible and chalcophile elements tend to be incompatible with magnetite, but in silicate systems some lithophile elements are incompatible and chalcophile elements are compatible with magnetite. Finally, comparison with magnetite data from other Ni-Cu-PGE sulfide deposits pinpoints that the nature of parental silicate magma, degree of sulfide evolution, cocrystallizing phases, and alteration conditions influence magnetite composition.

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9

Begg, G. C., J. A. M. Hronsky, N. T. Arndt, W. L. Griffin, S. Y. O'Reilly, and N. Hayward. "Lithospheric, Cratonic, and Geodynamic Setting of Ni-Cu-PGE Sulfide Deposits." Economic Geology 105, no. 6 (September 1, 2010): 1057–70. http://dx.doi.org/10.2113/econgeo.105.6.1057.

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10

Yakubchuk, Alexander, and Anatoly Nikishin. "Noril?sk?Talnakh Cu?Ni?PGE deposits: a revised tectonic model." Mineralium Deposita 39, no. 2 (March 1, 2004): 125–42. http://dx.doi.org/10.1007/s00126-003-0373-0.

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11

Naldrett, A. J. "World-class Ni-Cu-PGE deposits: key factors in their genesis." Mineralium Deposita 34, no. 3 (March 9, 1999): 227–40. http://dx.doi.org/10.1007/s001260050200.

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12

Brzozowski, M. J., I. M. Samson, J. E. Gagnon, D. J. Good, and R. L. Linnen. "On the Mechanisms for Low-Sulfide, High-Platinum Group Element and High-Sulfide, Low-Platinum Group Element Mineralization in the Eastern Gabbro, Coldwell Complex, Canada: Evidence from Textural Associations, S/Se Values, and Platinum Group Element Concentrations of Base Metal Sulfides." Economic Geology 115, no. 2 (March 1, 2020): 355–84. http://dx.doi.org/10.5382/econgeo.4708.

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Abstract The Eastern Gabbro, Coldwell Complex, hosts several geochemically and mineralogically distinct Cu-platinum group element (PGE) deposits, including the high-grade W Horizon (>100 ppm Pd-Pt-Au over 2 m). Several magmatic and/or hydrothermal models have previously been proposed to explain the range of enrichment in PGEs observed in the Marathon deposit, but no work has integrated textural and compositional variations in sulfides to elucidate which of these models is most suitable. Additionally, comparatively little work has been done to characterize the genesis of Cu-PGE mineralization that occurs to the northwest of the Marathon deposit in the Eastern Gabbro. Through integration of base metal sulfide (BMS) mineralogy, texture, and trace element chemistry, a wide range of magmatic and postmagmatic processes have been characterized that contributed to the formation of these deposits. In all zones of mineralization in the Eastern Gabbro, chalcophile elements were remobilized from primary chalcopyrite by hydrothermal fluids and precipitated as secondary chalcopyrite, which occurs as a replacement of pyrrhotite and as intergrowths with hydrous silicates. BMSs in the mineralized zones in the Marathon deposit (Footwall zone, Main zone, and W Horizon) experienced higher R factors than those deposits located northwest of the Marathon deposit (Four Dams, Area 41, and Redstone), with BMSs in the W Horizon having experienced the highest R factors. The silicate melts from which the Footwall zone crystallized likely experienced some degree of sulfide segregation at depth, albeit to a much lesser degree than the northern deposits. Additionally, the melts from which the mineralized zones in the Marathon deposit crystallized were likely contaminated by high-S/Se Archean sedimentary rocks, whereas the northern deposits were likely contaminated by low-S/Se igneous and/or metamorphic rocks. BMSs in a chalcopyrite-rich pod located within the vicinity of the Coldwell Complex experienced both high R factors and high degrees of contamination (cf. W Horizon and Footwall zone, respectively). This study illustrates the complexity of processes that generate and modify mineralization in conduit-type Ni-Cu-PGE systems.

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13

Acosta-Góngora, P., S. J. Pehrsson, H. Sandeman, E. Martel, and T. Peterson. "The Ferguson Lake deposit: an example of Ni–Cu–Co–PGE mineralization emplaced in a back-arc basin setting?" Canadian Journal of Earth Sciences 55, no. 8 (August 2018): 958–79. http://dx.doi.org/10.1139/cjes-2017-0185.

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The world’s largest Ni–Cu–Platinum group element (PGE) deposits are dominantly hosted by ultramafic rocks within continental extensional settings (e.g., Raglan, Voisey’s Bay), resulting in a focus on exploration in similar geodynamic settings. Consequently, the economic potential of other extensional tectonic environments, such as ocean ridges and back-arc basins, may be underestimated. In the northeastern portion of the ca. 2.7 Ga Yathkyed greenstone belt of the Chesterfield block (western Churchill Province, Canada), the Ni–Cu–Co–PGE Ferguson Lake deposit is hosted by >2.6 Ga hornblenditic to gabbroic rocks of the Ferguson Lake Igneous Complex (FLIC), which is metamorphosed up to amphibolitic facies. The FLIC has a basaltic composition (Mg# = 31–72), flat to slightly negatively sloped normalized trace element patterns (La/YbPM = 0.7–3.5), and negative Zr, Ti, and Nb anomalies. The FLIC rocks are geochemically similar to the 2.7 Ga back-arc basin tholeiitic basalts from the adjacent Yathkyed and MacQuoid greenstone belts (Mg# = 30–67; La/YbPM = 0.3–3.0), but the Ferguson Lake intrusions appear to be more crustally contaminated. We interpret the FLIC to have formed in an equivalent back-arc basin setting. This geodynamic setting is rare for the formation of Ni–Cu–PGE occurrences, and only few examples of this tectonic environment (or variations of it, e.g., rifted back-arc) are found in other Proterozoic and Archean sequences (e.g., Lorraine deposit, Quebec). We suggest that back-arc basin-derived mafic rocks within the Yathkyed and other Neoarchean greenstone belts of the Chesterfield block (MacQuoid and Angikuni) could represent important targets for future mineral exploration.

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14

Li, C., W. D. Maier, and S. A. de Waal. "Magmatic Ni-Cu versus PGE deposits: Contrasting genetic controls and exploration implications." South African Journal of Geology 104, no. 4 (December 1, 2001): 309–18. http://dx.doi.org/10.2113/gssajg.104.4.309.

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15

Barnes, Stephen J., Alexander R. Cruden, Nicholas Arndt, and Benoit M. Saumur. "The mineral system approach applied to magmatic Ni–Cu–PGE sulphide deposits." Ore Geology Reviews 76 (July 2016): 296–316. http://dx.doi.org/10.1016/j.oregeorev.2015.06.012.

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16

Boutroy, Emilie, Sarah A. S. Dare, Georges Beaudoin, Sarah-Jane Barnes, and Peter C. Lightfoot. "Magnetite composition in Ni-Cu-PGE deposits worldwide: application to mineral exploration." Journal of Geochemical Exploration 145 (October 2014): 64–81. http://dx.doi.org/10.1016/j.gexplo.2014.05.010.

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17

Le Vaillant, Margaux, Marco L. Fiorentini, and Stephen J. Barnes. "Review of lithogeochemical exploration tools for komatiite-hosted Ni-Cu-(PGE) deposits." Journal of Geochemical Exploration 168 (September 2016): 1–19. http://dx.doi.org/10.1016/j.gexplo.2016.05.010.

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18

Lesher, C. M. "Up, down, or sideways: emplacement of magmatic Fe–Ni–Cu–PGE sulfide melts in large igneous provinces." Canadian Journal of Earth Sciences 56, no. 7 (July 2019): 756–73. http://dx.doi.org/10.1139/cjes-2018-0177.

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The preferential localization of Fe–Ni–Cu–PGE sulfides within the horizontal components of dike–sill–lava flow complexes in large igneous provinces (LIPs) indicates that they were fluid dynamic traps for sulfide melts. Many authors have interpreted them to have collected sulfide droplets transported upwards, often from deeper “staging chambers”. Although fine (<1–2 cm) dilute (<10%–15%) suspensions of dense (∼4–5 g/cm3) sulfide melt can be transported in ascending magmas, there are several problems with upward-transport models for almost all LIP-related deposits: (1) S isotopic data are consistent with nearby crustal sources, (2) xenoliths appear to be derived from nearby rather than deeper crustal sources, (3) lateral sheet flow or sill facies of major deposits contain few if any sulfides, (4) except where there is evidence for a local S source, sulfides or chalcophile element enrichments rarely if ever occur in the volcanic components even where there is mineralization in the subvolcanic plumbing system, and (5) some lavas are mildly to strongly depleted in PGE >>> Cu > Ni > Co, indicating that unerupted sulfides sequestered PGEs at depth. Two potential solutions to this paradox are that (i) natural systems contained surfactants that lowered sulfide–silicate interfacial tensions, permitting sulfide melts to coalesce and settle more easily than predicted from theoretical/experimental studies of artificial/analog systems, and (or) (ii) sulfides existed not as uniformly dispersed droplets, as normally assumed, but as fluid-dynamically coherent pseudoslugs or pseudolayers that were large and dense enough that they could not be transported upwards. Regardless of the ultimate explanation, it seems likely that most high-grade Ni–Cu–PGE sulfide deposits in LIPs formed at or above the same stratigraphic levels as they are found.

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19

Eliopoulos, Demetrios G., and Maria Economou-Eliopoulos. "Trace Element Distribution in Magnetite Separates of Varying Origin: Genetic and Exploration Significance." Minerals 9, no. 12 (December 6, 2019): 759. http://dx.doi.org/10.3390/min9120759.

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Magnetite is a widespread mineral, as disseminated or massive ore. Representative magnetite samples separated from various geotectonic settings and rock-types, such as calc-alkaline and ophiolitic rocks, porphyry-Cu deposit, skarn-type, ultramafic lavas, black coastal sands, and metamorphosed Fe–Ni-laterites deposits, were investigated using SEM/EDS and ICP-MS analysis. The aim of this study was to establish potential relationships between composition, physico/chemical conditions, magnetite origin, and exploration for ore deposits. Trace elements, hosted either in the magnetite structure or as inclusions and co-existing mineral, revealed differences between magnetite separates of magmatic and hydrothermal origin, and hydrothermal magnetite separates associated with calc-alkaline rocks and ophiolites. First data on magnetite separates from coastal sands of Kos Island indicate elevated rare earth elements (REEs), Ti, and V contents, linked probably back to an andesitic volcanic source, while magnetite separated from metamorphosed small Fe–Ni-laterites occurrences is REE-depleted compared to large laterite deposits. Although porphyry-Cu deposits have a common origin in a supra-subduction environment, platinum-group elements (PGEs) have not been found in many porphyry-Cu deposits. The trace element content and the presence of abundant magnetite separates provide valuable evidence for discrimination between porphyry-Cu–Au–Pd–Pt and those lacking precious metals. Thus, despite the potential re-distribution of trace elements, including REE and PGE in magnetite-bearing deposits, they may provide valuable evidence for their origin and exploration.

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20

Moilanen, M., E. Hanski, J. Konnunaho, S. H. Yang, T. Törmänen, C. Li, and L. M. Zhou. "Re-Os isotope geochemistry of komatiite-hosted Ni-Cu-PGE deposits in Finland." Ore Geology Reviews 105 (February 2019): 102–22. http://dx.doi.org/10.1016/j.oregeorev.2018.12.007.

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21

Song, Xieyan, Yushan Wang, and Liemeng Chen. "Magmatic Ni-Cu-(PGE) deposits in magma plumbing systems: Features, formation and exploration." Geoscience Frontiers 2, no. 3 (July 2011): 375–84. http://dx.doi.org/10.1016/j.gsf.2011.05.005.

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22

Yao, Zhuo-sen, and James E. Mungall. "Kinetic controls on the sulfide mineralization of komatiite-associated Ni-Cu-(PGE) deposits." Geochimica et Cosmochimica Acta 305 (July 2021): 185–211. http://dx.doi.org/10.1016/j.gca.2021.05.009.

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23

Koivisto, Emilia, Alireza Malehmir, Pekka Heikkinen, Suvi Heinonen, and Ilmo Kukkonen. "2D reflection seismic investigations at the Kevitsa Ni-Cu-PGE deposit, northern Finland." GEOPHYSICS 77, no. 5 (September 1, 2012): WC149—WC162. http://dx.doi.org/10.1190/geo2011-0496.1.

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In 2007, a 2D reflection seismic survey was conducted at the Kevitsa Ni-Cu-PGE (platinum group elements) deposit in northern Finland. The aims of the survey were to delineate the overall extent of the ore-bearing Kevitsa ultramafic intrusive complex, to study the seismic response of the disseminated ore deposit, to potentially find indications for new ore deposits, and to extract structural information at depth that may be associated with mineralization. In the processing sequence, specific focus was given to finding optimal CDP-line geometries for the crooked-line survey profiles and, due to highly variable bedrock velocities, to detailed velocity analysis. Our conventional processing sequence, involving prestack DMO corrections followed by poststack migration, resulted in high-quality images of the subsurface. First, the data were used to establish the shape and extent of the Kevitsa intrusion, thus providing an overall framework for future exploration in the area. In particular, the data suggest deeper, up to about 1.5 km depth, continuation of the intrusion than previously thought. Furthermore, the images reveal variable reflectivity characteristics within the intrusion from nonreflective to internally reflective. The Kevitsa deposit is located within a part of the intrusion which is associated with distinct, gently dipping reflectivity fabric down to a depth of about 1 km, spatially constrained within a restricted zone internal to the intrusion. This zone can be used as a guideline for the near-mine exploration efforts, and the reflectivity is dominantly associated with magmatic layering controlling the extent of the bulk of economic mineralization. The seismic data also reveal a complex pattern of faults, in particular a series of major fault and shear zones bracketing and crosscutting the Kevitsa intrusion as a whole. Additionally, our interpretation of the data indicates a possible shared origin of the Kevitsa intrusion and the nearby Satovaara intrusion.

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24

Seat, Z., S. W. Beresford, B. A. Grguric, M. A. M. Gee, and N. V. Grassineau. "Reevaluation of the Role of External Sulfur Addition in the Genesis of Ni-Cu-PGE Deposits: Evidence from the Nebo-Babel Ni-Cu-PGE Deposit, West Musgrave, Western Australia." Economic Geology 104, no. 4 (July 1, 2009): 521–38. http://dx.doi.org/10.2113/gsecongeo.104.4.521.

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25

BEZRUKOV, VLADIMIR. "Major activities and provisional results of gold deposit forecasting in the eastern (Russian) part of Fennoscandian shield." Domestic geology, no. 2 (May 27, 2021): 28–40. http://dx.doi.org/10.47765/0869-7175-2021-10011.

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The paper discusses the main gold metallogeny features within foreign Precambrian shields (excluding sedimentary-metamorphogene deposits of Au-rich conglomerates and magmatogene Au-rich Cu-Ni and PGE deposits) and regional features of the eastern Fennoscandian shield. Data on geological setting of Finnish gold deposits are summarized and analyzed. The paper briefly reviews gold prospecting knowledge within Karelian-Kola region and work results. The author compiled a digital model of gold-specific forecast-metallogenic map for the eastern Fennoscandian shield; based on this model, further prioritized exploration activities in Karelian-Kola region are proposed, potential for discovering medium-sized and major deposits of various formational and geological/economic types is forecasted.

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26

Mikulski, Stanisław Z., Sławomir Oszczepalski, Katarzyna Sadłowska, Andrzej Chmielewski, and Rafał Małek. "Trace Element Distributions in the Zn-Pb (Mississippi Valley-Type) and Cu-Ag (Kupferschiefer) Sediment-Hosted Deposits in Poland." Minerals 10, no. 1 (January 17, 2020): 75. http://dx.doi.org/10.3390/min10010075.

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We applied geochemical (ICP-MS, WD-XRF, GFAAS, and AMA 254) and mineralogical (EPMA) studies of 137 samples to ore mineralization from Middle-Triassic sediment-hosted Zn-Pb (Mississippi Valley-type MVT) and Lower Zechstein sediment-hosted stratiform (SSC) Cu-Ag (Kupferschiefer-type) deposits in Poland. They contain a number of trace elements which are not recovered during the ore processing. Only Cu, Ag, Pb, Ni, Re, Se, Au, and PGE are extracted from Cu-Ag deposits while Zn and Pb are the only elements produced from Zn-Pb deposits. Zn-Pb deposits contain Cd, Ag, Ga, and Ba in slightly elevated concentrations and have potential to be mineral resources. This applies to a lesser extent to other trace elements (Bi, As, Hf, Tl, Sb, Se, and Re). However, only Cd and Ag show high enrichment factors indicative of potential for recovery. The bulk-rock analyses reveal strong correlations between Zn and Cd and Se, As and Mo, and weaker correlations between Ag and Cd, as well as Ga and Zn. Electron microprobe analyses of sphalerite revealed high concentrations of Cd (≤2.6 wt%) and Ag (≤3300 ppm). Zn-Pb deposits have fairly significant estimated resources of Ga and Sc (>1000 tons) and Cd (>10,000 tons). The Cu-Ag deposits have element signatures characterized by high values of Co, V, Ni, and Mo and much lower of Bi, As, Cd, Hg, Mo, Sb, and Tl. Bulk-rock analyses show strong correlations between Se and V; As and Co; Bi and Re; and weaker correlations between, for example, Cu and Mo; V, Ni, Ag and Mo; and Ni, V, and Co and Ni. The EPMA determinations reveal strong enrichments of Ag in Cu sulfides (geerite ≤ 10.1 wt %, chalcocite ≤ 6.28 wt %, bornite ≤ 3.29 wt %, djurleite ≤ 9080 ppm, yarrowite ≤ 6614 ppm, and digenite ≤ 3545 ppm). Silver minerals and alloys, as well as the native Ag and Au, were recorded in the Cu-Ag ores. Large resources of Co, V, and Ni (>100,000 tons) and Sc and Mo (>10,000 tons) are notable in Cu-Ag deposits. A number of trace elements, classified as critical for the economy of the European Union, including Ga and Ba (to a lesser extent Hf, Nb, and Sc) in Zn-Pb deposits, and Co and V in the Cu-Ag deposits, may eventually be recovered in the future from the studied deposits if proper ore-processing circuits and increasing demand are favorable.

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27

TANG, Zhongli, Haiqing YAN, Jiangang JIAO, and Zhenxing PAN. "Regional Metallogenic Controls of Small-intrusion-hosted Ni-Cu (PGE) Ore Deposits in China." Earth Science Frontiers 14, no. 5 (September 2007): 92–101. http://dx.doi.org/10.1016/s1872-5791(07)60038-4.

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28

Wright, A. J., J. Parnell, and D. E. Ames. "Carbon spherules in Ni–Cu–PGE sulphide deposits in the Sudbury impact structure, Canada." Precambrian Research 177, no. 1-2 (February 2010): 23–38. http://dx.doi.org/10.1016/j.precamres.2009.11.002.

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29

Maier, Wolfgang D., and David I. Groves. "Temporal and spatial controls on the formation of magmatic PGE and Ni–Cu deposits." Mineralium Deposita 46, no. 8 (March 2, 2011): 841–57. http://dx.doi.org/10.1007/s00126-011-0339-6.

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30

Krivolutskaya, Nadezhda A., Anton V. Latyshev, Alexander S. Dolgal, Bronislav I. Gongalsky, Elena M. Makarieva, Alexander A. Makariev, Natalia M. Svirskaya, Yana V. Bychkova, Anton I. Yakushev, and Alexey M. Asavin. "Unique PGE–Cu–Ni Noril’sk Deposits, Siberian Trap Province: Magmatic and Tectonic Factors in Their Origin." Minerals 9, no. 1 (January 21, 2019): 66. http://dx.doi.org/10.3390/min9010066.

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The unique and very large PGE–Cu–Ni Noril’sk deposits are located within the Siberian trap province, posing a number of questions about the relationship between the ore-forming process and the magmatism that produced the traps. A successful answer to these questions could greatly increase the possibility of discovering new deposits in flood basalt provinces elsewhere. In this contribution, we present new data on volcanic stratigraphy and geochemistry of the magmatic rocks in the key regions of the Siberian trap province (Noril’sk, Taimyr, Maymecha-Kotuy, Kulyumber, Lower Tunguska and Angara) and analyze the structure of the north part of the province. The magmatic rocks of the Arctic zone are characterized by variable MgO (3.6–37.2 wt %) and TiO2 (0.8–3.9 wt %) contents, Gd/Yb (1.4–6.3) and La/Sm (2.0–10.4) ratios, and a large range of isotopic compositions. The intrusions in the center of the Tunguska syneclise and Angara syncline have much less variable compositions and correspond to a “typical trap” with MgO of 5.6–7.2 wt %, TiO2 of 1.0–1.6 wt %, Gd/Yb ratio of 1.4–1.6 and La/Sm ratio of 2.0–3.5. This compositional diversity of magmas in the Arctic zone is consistent with their emplacement within the paleo-rift zones. Ore-bearing intrusions (the Noril’sk 1, Talnakh, Kharaelakh) are deep-situated in the Igarka-Noril’sk rift zone, which has three branches, namely the Bolsheavamsky, Dyupkunsky, and Lower Tunguska, that are prospected for discovering new deposits. One possible explanation for the specific position of the PGE–Cu–Ni deposits is accumulation of sulfides in these long-lived zones from the Neoproterozoic to the Mesozoic era during magmatic and metamorphic processes. Thus, trap magmatism, itself, does not produce large deposits, but mobilizes earlier formed sulfide segregations in addition carrying metals in the original magmas. These deposits are the results of several successive magmatic events, in which emplacement of the traps was the final event.

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Parnell, John, Connor Brolly, and Adrian J. Boyce. "Graphite from Palaeoproterozoic enhanced carbon burial, and its metallogenic legacy." Geological Magazine 158, no. 9 (July 13, 2021): 1711–18. http://dx.doi.org/10.1017/s0016756821000583.

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AbstractThe episode of widespread organic carbon deposition marked by peak black shale sedimentation during the Palaeoproterozoic is also reflected in exceptionally abundant graphite deposits of this age. Worldwide anoxic/euxinic sediments were preserved as a deep crustal reservoir of both organic carbon, and sulphur in accompanying pyrite, both commonly >1 wt %. The carbon- and sulphur-rich Palaeoproterozoic crust interacted with mafic magma to cause Ni–Co–Cu–PGE mineralization over the next billion years, and much uranium currently produced is from Mesoproterozoic deposits nucleated upon older Palaeoproterozoic graphite. Palaeoproterozoic carbon deposition has thus left a unique legacy of both graphite deposits and long-term ore deposition.

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Krivolutskaya, Nadezhda, Sheida Makvandi, Bronislav Gongalsky, Irina Kubrakova, and Natalia Svirskaya. "Chemical Characteristics of Ore-Bearing Intrusions and the Origin of PGE–Cu–Ni Mineralization in the Norilsk Area." Minerals 11, no. 8 (July 28, 2021): 819. http://dx.doi.org/10.3390/min11080819.

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The composition of the parental magmas of Cu–Ni deposits is crucial for the elucidation of their genesis. In order to estimate the role of magma in ore formation, it is necessary to compare the compositions of silicate rock intrusions with different mineralization patterns, as observed in the Norilsk region. The rock geochemistry of two massifs located in the same Devonian carbonate rocks—the Kharaelakh intrusion, with its world-class platinum-group element (PGE)–Cu–Ni deposit, and the Pyasinsky-Vologochansky intrusion, with its large deposit—was studied. Along with these massifs, the Norilsk 2 massif with noneconomic mineralization intruded in the Ivakinskaya-Nadezhdinskaya basalts was studied as well. Their settings allow the estimation of the parental magma composition, taking into account the possible assimilation of host rocks. Analyses of 39 elements in 97 samples demonstrated the similarity of the intrusions in terms of their major components. The Pyasinsky-Vologochansky intrusion contains the highest trace element contents compared with the Kharaelakh and Norilsk 2 massifs, evidencing its crystallization from evolved parental magma. No influence of host rocks on the silicate rock compositions was found, except for narrow (1–2 m) endo-contact zones. There is no correlation between the mineralization volume and the rock compositions of the studied intrusions. It is assumed that the intrusions were formed from one magma crustal source irregularly rich in sulfur (S). This source inhomogeneity in terms of the sulfur distribution resulted in deposits of varying sizes. The magmas served as a transporting agent for sulfides from deep zones to the surface.

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Ripley, E. M. "SULFUR ISOTOPE EXCHANGE AND METAL ENRICHMENT IN THE FORMATION OF MAGMATIC Cu-Ni-(PGE) DEPOSITS." Economic Geology 98, no. 3 (May 1, 2003): 635–41. http://dx.doi.org/10.2113/98.3.635.

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Ripley, Edward M., and Chusi Li. "SULFUR ISOTOPE EXCHANGE AND METAL ENRICHMENT IN THE FORMATION OF MAGMATIC Cu-Ni-(PGE) DEPOSITS." Economic Geology 98, no. 3 (May 2003): 635–41. http://dx.doi.org/10.2113/gsecongeo.98.3.635.

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RIPLEY, Edward M., and Chusi LI. "Applications of Stable and Radiogenic Isotopes to Magmatic Cu-Ni-PGE Deposits: Examples and Cautions." Earth Science Frontiers 14, no. 5 (September 2007): 124–31. http://dx.doi.org/10.1016/s1872-5791(07)60041-4.

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Starostin, V. I., and O. G. Sorokhtin. "A new interpretation for the origin of the Norilsk type PGE–Cu–Ni sulfide deposits." Geoscience Frontiers 2, no. 4 (October 2011): 583–91. http://dx.doi.org/10.1016/j.gsf.2011.09.005.

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37

Kawohl, Alexander, Wesley E. Whymark, Andrejs Bite, and Hartwig E. Frimmel. "High-Grade Magmatic Platinum Group Element-Cu(-Ni) Sulfide Mineralization Associated with the Rathbun Offset Dike of the Sudbury Igneous Complex (Ontario, Canada)." Economic Geology 115, no. 3 (May 1, 2020): 505–25. http://dx.doi.org/10.5382/econgeo.4717.

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Abstract Quartz dioritic impact melt dikes around the 1.85 Ga Sudbury Igneous Complex, locally referred to as offset dikes, are well endowed with respect to Ni-Cu-platinum group elements (PGE). However, only those dikes proximal (<6 km) to the main mass of the Sudbury Complex are mineralized at an economic grade and, in places, host world-class deposits. We report on a new discovery of such heavily mineralized offset dike at Rathbun Lake, about 15 km east of the currently known extent of the Sudbury Igneous Complex. There, a segment of amphibole quartz diorite is exposed at the contact between Huronian metasedimentary rocks and gabbro of the 2.22 Ga Nipissing Suite, xenoliths of which are abundant throughout the diorite and record textural evidence of partial melting. The mafic inclusion-bearing quartz diorite is the host of the Rathbun Lake showing, a small but high-grade PGE-Cu(-Ni) sulfide occurrence of hitherto controversial origin. A detailed petrographic and mineralogical characterization of this occurrence revealed a two-stage mineralization history. Disseminated to semimassive (net-textured) chalcopyrite ± loop-textured pentlandite ± magnetite containing Pd-bismuthotellurides and, more rarely, sperrylite and native gold—all of which are closely associated with base metal sulfides—are interpreted as magmatic. The semimassive sulfide averages ~40 g/t Pd + Pt + Au at a Cu/(Cu + Ni) of >0.9 and a Pd/Ir of >100,000. Mineralogy, ore textures, and mantle-normalized PGE + Au patterns match a specific type of Cu-rich mineralization in the Sudbury Igneous Complex known as footwall mineralization. By analogy with these footwall deposits, the occurrence is interpreted as having formed by downward percolation of a highly fractionated sulfide melt toward the bottom of a now largely eroded offset dike. The magmatic paragenesis was hydrothermally overprinted at lower greenschist-facies conditions to pyrite-chalcopyrite-violarite ± covellite ± millerite. This involved also local remobilization into pyrite-chalcopyrite veinlets and the liberation of precious metal minerals from their sulfide hosts. In contrast to base metal sulfides, most precious metal minerals were resistant to hydrothermal alteration, although corrosion of some grains is noted as well as their truncation by chlorite and epidote. Micron-scale X-ray mapping revealed a progressive replacement of magmatic Pd-Bi-Te minerals, where in contact with hydrous silicates, by Sb- and Hg-bearing Pd minerals such as temagamite, Pd3HgTe3. The timing and nature of this hydrothermal overprint remains uncertain, but a connection to later regional metamorphism and faulting seems most plausible. Our finding of magmatic PGE-base metal sulfide at Rathbun Lake suggests a new subtype of distal offset dike-hosted mineralization in an area so far not known for offset dikes. It opens up new opportunities in the search for unconventional ore deposits around the Sudbury impact structure and improves our understanding on the distribution of impact melt-derived dikes around complex craters.

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Järvinen, Ville, Tapio Halkoaho, Jukka Konnunaho, Jussi S. Heinonen, and O. Tapani Rämö. "Parental magma, magmatic stratigraphy, and reef-type PGE enrichment of the 2.44-Ga mafic-ultramafic Näränkävaara layered intrusion, Northern Finland." Mineralium Deposita 55, no. 8 (December 31, 2019): 1535–60. http://dx.doi.org/10.1007/s00126-019-00934-z.

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AbstractAbout 20 mafic-ultramafic layered intrusions in the northern Fennoscandian shield were emplaced during a widespread magmatic event at 2.5–2.4 Ga. The intrusions host orthomagmatic Ni-Cu-PGE and Cr-V-Ti-Fe deposits. We update the magmatic stratigraphy of the 2.44-Ga Näränkävaara mafic-ultramafic body, northeastern Finland, on the basis of new drill core and outcrop observations. The Näränkävaara body consists of an extensive basal dunite (1700 m thick), and a layered series comprising a peridotitic–pyroxenitic ultramafic zone (600 m thick) and a gabbronoritic–dioritic mafic zone (700 m thick). Two reversals are found in the layered series. The composition of the layered series parental magma was approximated using a previously unidentified marginal series gabbronorite. The parental magma was siliceous high-Mg basalt with high MgO, Ni, and Cr, but also high SiO2 and Zr, which suggests primary magma contamination by felsic crust. Cu/Pd ratio below that of primitive mantle implies PGE-fertility. The structural position of the marginal series indicates that the thick basal dunite represents an older wallrock for the layered intrusion. A subeconomic reef-type PGE-enriched zone is found in the border zone between the ultramafic and mafic zones and has an average thickness of 25 m with 150–250 ppb of Pt + Pd + Au. Offset-type metal distribution and high sulfide tenor (50–300 ppm Pd) and R-factor (105) suggest reef formation by sulfide saturation induced by fractional crystallization. The reef-forming process was probably interrupted by influx of magma related to the first reversal. Metal ratios suggest that this replenishing magma was PGE-depleted before emplacement.

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Mungall, James E., M. Christopher Jenkins, Samuel J. Robb, Zhuosen Yao, and James M. Brenan. "UPGRADING OF MAGMATIC SULFIDES, REVISITED." Economic Geology 115, no. 8 (October 23, 2020): 1827–33. http://dx.doi.org/10.5382/econgeo.4775.

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Abstract There has been vigorous debate for several decades about whether the extreme enrichments of platinum group elements (PGEs) in some magmatic sulfide deposits could have resulted from simple equilibration of sulfide liquid with silicate melt. Key examples include the Ni-Cu-Pd mineralization in the Norilsk mining camp, the UG2 and Merensky reef Pt-Pd deposits in the Bushveld Complex, the Pd-rich J-M reef of the Stillwater Complex, and the Skaergaard Pd-Au mineralization. It was argued historically that the observed PGE tenors in these latter deposits are too high to be consistent with simple equilibration of sulfide and silicate melt. A commonly cited mechanism for increasing PGE tenor in magmatic sulfide is the upgrading of initially low tenor sulfide by allowing a small volume of sulfide to react with successive batches of fresh, previously undepleted silicate magma. Here we review several previous models for sulfide upgrading in light of recent changes in accepted values of the partition coefficients governing PGE exchange between sulfide and silicate, and we critically examine the physical scenarios implicit in each previous model. We show that, although sulfide upgrading may occur in natural settings such as fractional melting of the mantle, during the formation of sulfide accumulations from magmas it is unlikely to have effects that can be distinguished from simple one-stage batch equilibration. Even the most PGE-rich deposits currently known have compositions that can easily be accounted for by the simple one-stage batch process, with the possible exception of the Skaergaard Pd mineralization. It is generally not possible to use the measured composition of accumulations of magmatic sulfide to infer that sulfide upgrading has or has not occurred.

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Smith, W. D., W. D. Maier, I. Bliss, and L. Martin. "In Situ Multiple Sulfur Isotope and S/Se Composition of Magmatic Sulfide Occurrences in the Labrador Trough, Northern Quebec." Economic Geology 116, no. 7 (November 1, 2021): 1669–86. http://dx.doi.org/10.5382/econgeo.4843.

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Abstract The interaction between mafic-ultramafic magma and crustal sulfide is considered a key process in the formation of magmatic Ni-Cu-platinum group element (PGE) sulfide deposits. Integrated S/Se and multiple sulfur isotope studies are the most robust in constraining the role of crustal sulfur during ore genesis. In the present study, we report the first integrated S/Se and multiple sulfur isotope study of magmatic sulfide occurrences in the Labrador Trough, namely, on the recently discovered Idefix PGE-Cu and Huckleberry Cu-Ni-(PGE) prospects. Whole-rock and in situ S/Se values (~810–3115) of magmatic sulfides and their host rocks are consistent with S loss during postmagmatic hydrothermal alteration, negating their use in interpreting the origin of S. Values of ∆33S ~0 indicate no record of the assimilation of Archaean sulfur. Disseminated (–0.5 to +2.5‰) and globular (3.0–4.5‰) sulfides at Idefix as well as globular sulfides (2.1–9.6‰) at Huckleberry have δ34S values greater than the accepted mantle range, suggesting that crustal S played a role in the formation of these sulfides. In contrast, disseminated and net-textured sulfides at Huckleberry have variable δ34S values (–4.6 to +3.2‰) that are mostly within the accepted mantle range, excluding one anomalous sample that records relatively higher δ34S values (11.9–15.0‰). It is proposed that sulfide melt segregated in response to the addition of small proportions of crustal S prior to the final emplacement of the host intrusions, i.e., in a feeder conduit or staging chamber. Isotopic exchange between the sulfide melt and silicate magma has diluted and, in places, eradicated a crustal δ34S signature.

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Arndt, N. T. "Geochemistry and Origin of the Intrusive Hosts of the Noril'sk-Talnakh Cu-Ni-PGE Sulfide Deposits." Economic Geology 98, no. 3 (May 1, 2003): 495–515. http://dx.doi.org/10.2113/98.3.495.

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Farrow, Catharine E. G., David H. Watkinson, and Peter C. Jones. "Fluid inclusions in sulfides from North and South Range Cu-Ni-PGE deposits, Sudbury Structure, Ontario." Economic Geology 89, no. 3 (May 1, 1994): 647–55. http://dx.doi.org/10.2113/gsecongeo.89.3.647.

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43

Lambert, David D., Jeffrey G. Foster, Louise R. Frick, Edward M. Ripley, and Michael L. Zientek. "Geodynamics of magmatic Cu-Ni-PGE sulfide deposits; new insights from the Re-Os isotope system." Economic Geology 93, no. 2 (April 1, 1998): 121–36. http://dx.doi.org/10.2113/gsecongeo.93.2.121.

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Svetlitskaya, Tatyana V., Peter A. Nevolko, Thi Phuong Ngo, Trong Hoa Tran, Andrey E. Izokh, Roman A. Shelepaev, An Nien Bui, and Hoang Ly Vu. "Small-intrusion-hosted Ni-Cu-PGE sulfide deposits in northeastern Vietnam: Perspectives for regional mineral potential." Ore Geology Reviews 86 (June 2017): 615–23. http://dx.doi.org/10.1016/j.oregeorev.2017.03.024.

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45

Barnes, Stephen J., James E. Mungall, Margaux Le Vaillant, Belinda Godel, C. Michael Lesher, David Holwell, Peter C. Lightfoot, Nadya Krivolutskaya, and Bo Wei. "Sulfide-silicate textures in magmatic Ni-Cu-PGE sulfide ore deposits: Disseminated and net-textured ores." American Mineralogist 102, no. 3 (March 2017): 473–506. http://dx.doi.org/10.2138/am-2017-5754.

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46

Song, Xie-Yan, Mei-Fu Zhou, Zhi-Min Cao, Min Sun, and Yun-Liang Wang. "Ni?Cu?(PGE) magmatic sulfide deposits in the Yangliuping area, Permian Emeishan igneous province, SW China." Mineralium Deposita 38, no. 7 (October 1, 2003): 831–43. http://dx.doi.org/10.1007/s00126-003-0362-3.

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47

Abzalov, M. Z., and R. A. Both. "The Pechenga Ni-Cu deposits, Russia: Data on PGE and Au distribution and sulphur isotope compositions." Mineralogy and Petrology 61, no. 1-4 (1997): 119–43. http://dx.doi.org/10.1007/bf01172480.

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Barkov, Andrei, and Louis Cabri. "Variations of Major and Minor Elements in Pt–Fe Alloy Minerals: A Review and New Observations." Minerals 9, no. 1 (January 4, 2019): 25. http://dx.doi.org/10.3390/min9010025.

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Compositional variations of major and minor elements were examined in Pt–Fe alloys from various geological settings and types of deposits, both lode and placer occurrences. They included representatives of layered intrusions, Alaskan-Uralian-(Aldan)-type and alkaline gabbroic complexes, ophiolitic chromitites, and numerous placers from Canada, USA, Russia, and other localities worldwide. Pt–Fe alloy grains in detrital occurrences are notably larger in size, and these are considered to be the result of a special conditions during crystallization such as temperature, pressure, geochemistry or time. In addition, the number of available statistical observations is much greater for the placer occurrences, since they represent the end-product of, in some cases, the weathering of many millions of tonnes of sparsely mineralized bedrock. Typically, platinum-group elements (PGE) present in admixtures (Ir, Rh, and Pd) and minor Cu, Ni are incorporated into a compositional series (Pt, PGE)2–3(Fe, Cu, Ni) in the lode occurrences. Relative Cu enrichment in alloys poor in Pt implies crystallization from relatively fractionated melts at a lower temperature. In contrast to the lode deposits, the distribution of Ir, Rh, and Pd is fairly chaotic in placer Pt–Fe grains. There is no relationship between levels of Ir, Rh, and Pd with the ratio Σ(Pt + PGE):(Fe + Cu + Ni). The compositional series (Pt, PGE)2–3(Fe, Cu, Ni) is not as common in the placer occurrences; nevertheless, minor Cu and Ni show their maximums in members of this series in the placer grains. Global-scale datasets yield a bimodal pattern of distribution in the Pt–Fe diagram, which is likely a reflection of the miscibility gap between the ordered Pt3Fe structure (isoferroplatinum) and the disordered structure of native or ferroan platinum. In the plot Pt versus Fe, there is a linear boundary due to ideal Pt ↔ Fe substitution. Two solid solution series are based on the Ir-for-Pt and Pd-for-Pt substitutions. The incorporation of Ir is not restricted to Pt3Fe–Ir3Fe substitution (isoferroplatinum and chengdeite, plus their disordered modifications). Besides, Ir0 appears to replace Pt0 in the disordered variants of (Pt–Ir)–Fe alloys. There is a good potential for the discovery of a new species with a Pd-dominant composition, (Pd, Pt)3Fe, most likely in association with the alkaline mafic-ultramafic or gabbroic complexes, or the mafic units of layered intrusions. The “field of complicated substitutions” is recognized as a likely reflection of the crystallochemical differences of Pd and Ir, extending along the Ir-Pd axis of the Ir–Pd–Rh diagram. The inferred solid solution extends approximately along the line Ir–(Pd:Rh = 2:3). Minor Pd presumably enters the solid solution via a coupled substitution in combination with the Rh. An Ir-enrichment trend in Pt–Fe alloys typically occurs in the Alaskan-type complexes. The large size of the Pt–Fe nuggets associated with some of these complexes is considered to be related to an ultramafic-mafic pegmatite facies, whereas significant Pd-enrichment is characteristic of gabbroic source-rocks (e.g., Coldwell Complex), resulting in a markedly different trend for the Pt versus Fe (wt.%). However, based on our examination of a large dataset of Pt–Fe alloys from numerous origins, we conclude that they exhibit compositional overlaps that are too large to be useful as reliable index-minerals.

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Fiorentini, M. L., S. W. Beresford, and M. E. Barley. "Controls on the genesis and emplacement of komatiite-hosted Ni–Cu–PGE-sulphides at Albion Downs (Agnew-Wiluna Belt, Western Australia): a case study on the development of PGE lithogeochemical vectors to Ni–Cu–PGE-sulphide deposits." Applied Earth Science 116, no. 4 (December 2007): 152–66. http://dx.doi.org/10.1179/174327507x207500.

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Fiorentini, M. L., S. W. Beresford, and M. E. Barley. "RUTHENIUM-CHROMIUM VARIATION: A NEW LITHOGEOCHEMICAL TOOL IN THE EXPLORATION FOR KOMATIITE-HOSTED Ni-Cu-(PGE) DEPOSITS." Economic Geology 103, no. 2 (March 1, 2008): 431–37. http://dx.doi.org/10.2113/gsecongeo.103.2.431.

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