Geology of Ore Deposits最新文献

{"title":"Geochemistry and P-T Conditions of Hydrothermal Fluids Associated with Porphyry, Metasomatic and Epithermal Ore Deposits at Oued Belif-Ain El Araar Magmatic Structure (North-African Alpine Orogeny, Tunisia)","authors":"Ben Aissa Wiem, Gardien Véronique, Ben Aissa Rania, Ben Haj Amara Abdessalem, Tlig Said, Ben Aissa Lassaad","doi":"10.1134/s1075701523060028","DOIUrl":"https://doi.org/10.1134/s1075701523060028","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Copper-rich deposits associated with magmatism at the Oued Belif -Ain El Araar area in North-western Tunisia fit into the geodynamic framework of the Tell-Rif orogenic belt of North Africa that extends westward to the Betic Cordilleras in Spain at the african and european plate boundary. The deposits have been considerably studied. However, the prevailing conditions of pressure, volume, temperature and composition (P-V-T-X) of the mineralizing fluids are still elusive. In this study, three types of fluid inclusions were distinguished for the mineralized facies: primary polyphase brine inclusions (Type I: liquid + vapor + halite + sylvite), primary sylvite (Type II-a: liquid + vapor + sylvite) and halite (Type II-b: liquid + vapor + halite) bearing inclusions and biphasic secondary vapor-rich and liquid-rich inclusions (Type III: liquid + vapor). Raman spectroscopy show that Type I and II a-b inclusions are in the CO₂–H₂O–NaCl–KCl, CO₂–H₂O–NaCl and CO₂–H₂O–KCl systems, whereas Type III pertains to the CO₂–H₂O system. Estimations of Pressure-Temperature fluid trapping conditions, for all mentioned inclusions, demonstrate a physicochemical fluid evolution from the highest temperature brine inclusions (<i>T</i>_t = 500°C; <i>P</i>_t = 980 bars), related to the porphyry phase, to the low temperature biphasic inclusions (<i>T</i>_t = 131°C; <i>P</i>_t = 221 bars) related the latest epithermal phase .The coexistence of liquid-rich and vapor-rich inclusions homogenizing at lower temperatures, confirms the establishment of boiling conditions responsible of Au–(Ag) enrichment in the last mineralizing phases. Comparable temperature conditions in similar magmatic related deposits are also mentioned in southern Spain (Rodalquilar gold mine, e.g., Arribas et al., 1995) where the mineralizing fluid temperatures mentioned vary from 175°C for epithermal deposits to more than 400°C for porphyry ones. The geochemical behavior of trace element indicates positive anomalies in mobile elements (hygromagmaphiles), those linked to Au, granitophiles (mainly W and Mo) and chalcophiles indicating a supply of metals of deep origin and mineralizing fluids with marked magmatic differentiation.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"62 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of Rare-Metal Li–F Granite Melts in Sources of Ore-Magmatic Systems of Tigrinoe and Zabytoe Sn–W deposits (Central Sikhote-Alin, Primorye)","authors":"O. A. Gavryushkina, E. N. Sokolova, S. Z. Smirnov, N. N. Kruk, A. V. Ponomarchuk, V. G. Tomas","doi":"10.1134/s1075701523060041","DOIUrl":"https://doi.org/10.1134/s1075701523060041","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The present paper considers petrographic and geochemical features of rocks of the Tigrinoe and Zabytoe stocks, provides their mineral composition, the results of the detailed study of micas and mineral-forming inclusions in quartz. It is shown that the development of ore-magmatic systems (OMSs) of the Zabytoe and Tigrinoe deposits is associated with the same rare-metal Li–F melts. It is confirmed that granitoids of the Tigrinoe stock can be considered as more differentiated analogs of granitoids of the Zabytoe stock. New data concerning the differences in the history of the magmatic stage of development of the OMSs of these deposits are presented. The evolution of melts of both deposits took place at high fluid pressure. Differences in the scale of ore mineralization of the two RMSs under consideration could be due to different fluid regime of magmatic sources evolution and more significant participation of transmagmatic fluid flows in the development of the Tigrinoe OMS.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"135 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxygen Isotope Geochemistry as a Tool in the Exploration for BIF-hosted Iron Ore Occurrences within the Precambrian Mineral Belt of Southern Cameroon, Northwestern Margin of the Congo Craton: A Review","authors":"G. L. Ngiamte, O. A. Okunlola, C. E. Suh, D. C. I. Ilouga, R. B. Ngatcha, N. Y. Njamnsi, N. A. Afahnwie, S. C. Tufion","doi":"10.1134/s1075701523060077","DOIUrl":"https://doi.org/10.1134/s1075701523060077","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>As a method for discovering the footprint of concealed iron ore enrichments, oxygen isotopes have revealed hydrothermal fluid sources and processes in Banded Iron Formation (BIF)-hosted iron ore provinces worldwide. This paper reviews the role oxygen isotopes play in exploring BIF-hosted iron ore bodies and discusses their application in southern Cameroon’s Precambrian mineral belt as an auxiliary exploration technique. Oxygen isotope analysis of iron ore species (e.g., BIFs, itabirites, and jaspilites) showed that the least altered BIFs had higher δ¹⁸O values than enriched ores. In the Nyong complex BIF sequence of southern Cameroon, δ¹⁸O_mag values range from –3 to –1.8, while δ¹⁸O_qtz values range from 6.8 to 10.6, indicating a discernible shift between the δ¹⁸O_mag-qtz values. Much higher δ¹⁸O_mag values (2.89 to 9.30‰) have been observed for magnetite gneisses suggesting an evolved magmatic-hydrothermal fluid source. Quartz veins associated with early-stage hematite ores in the adjacent Ivindo basement complex display higher δ¹⁸O values (4.7 to 8.1%) than those associated with late-stage magnetite ores (–2.3 to –1.5%). It is evident from these values that there is an isotopic shift between early-stage and late-stage iron ores, supporting the relevance of oxygen isotope to understanding iron ore signatures within the NW margin of the Congo craton. However, since the Congo Basin is characterised by inaccessible equatorial vegetation cover and lacks superficial exposures, high-precision oxygen isotopes (δ¹⁸O and δ¹⁷O) in conjunction with other isotopic techniques (e.g., δ⁵⁶Fe) and lithogeochemistry, will be more useful in constraining the isotopic signature of the BIF mineralisation.</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"1 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manganese Sturmanite from the N’Chwaning 2 Mine, Kalahari, South Africa","authors":"","doi":"10.1134/s1075701523070036","DOIUrl":"https://doi.org/10.1134/s1075701523070036","url":null,"abstract":"<span> <h3>Abstract</h3> <p>The oxidation state of Mn is determined for the first time by iodine titrimetry, and the Mn⁴⁺/Mn³⁺ ratio (54/46%) is identified for Mn-sturmanite from the N’Chwaning 2 Mine (Kalahari manganese field, South Africa). The Mössbauer spectrum of sturmanite, which contains a single asymmetric Lorentz doublet with parameters ^RTIS_α-Fe = 0.31(1) mm/s, ^RTQS = 0.18(1) mm/s, FWHM_L = 0.55 mm/s, and FWHM_R = 0.33 mm/s, confirms the presence of Fe³⁺ only in the composition of the mineral. The process of its thermal transformation is studied using thermal analysis and IR spectroscopy: dehydration and decomposition of Ca polyhedra, dehydroxylation, decarbonatization, and complete decomposition of structure with the formation of anhydrite, hematite, and Ca borates occur up to 200, 600, 750, and 1000°C, respectively. The chemical formula of the studied sturmanite, which is calculated on the basis of our studies per eight cations, is as follows: Ca_5.94<span> <span>({text{Fe}}_{{1.03}}^{{3 + }}{text{Mn}}_{{0.54}}^{{4 + }}{text{Mn}}_{{0.44}}^{{3 + }})</span> </span>Al_0.03Si_0.02[B(OH)₄]_1.00[B(OH)₃]_0.11[SO₄]_2.32[СО₃]_0.49(OH)₁₂⋅22.7H₂O. The unit cell parameters of the mineral are determined using X-ray powder diffraction: <em>a</em> = 11.148(3) Å, <em>c</em> = 21.830(9) Å, and <em>V</em> = 2349(2) ų. The unit cell parameters of minerals of the sturmanite–jouravskite series linearly decrease with an increasing mole amount of the jouravskite endmember. It is suggested that the studied mineral can be an intermediate member of the sturmanite–jouravskite series with heterovalent isomorphic substitution according to following schemes: Mn³⁺ and Mn⁴⁺ → Fe³⁺ in the cation octahedral site and [CO₃]^2– → [B(OH)₄]^– and [SO₄]^2– in the anion site.</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"23 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maldonite and Products of Its Replacement—Pure Native Gold, Jonassonite, and Bismuthic Aurostibite—in Gold Ores of the Darasun Deposit (Eastern Transbaikalia)","authors":"","doi":"10.1134/s1075701523070103","DOIUrl":"https://doi.org/10.1134/s1075701523070103","url":null,"abstract":"<span> <h3>Abstract</h3> <p>The Late Jurassic orogenic volcanogenic–plutonogenic Darasun gold deposit of the beresite–listvenite gold–sulfide–quartz formation is situated in the Mesozoids of the Eastern Transbaikalian segment of the Mongol–Okhotsk folded belt. The deposit includes Au–Bi–Te and the postgold Sb mineralization. Carbonate–quartz–sulfide veins in the Western block of the deposit composed of gabbroids, gabbro amphibolites, and, to a lesser extent, ultramafic rocks are surrounded by listvenite aureoles. Au-rich ores were formed under conditions of the low activity of sulfide sulfur; they are enriched in pyrrhotite and contain bismuthine and/or Pb–Bi sulfosalts and, locally, rare nests of native bismuth and ikunolite Bi₄S₃. The high-fineness gold (970–925) associates with bismuthinite and Pb–Bi sulfosalts. Instead of native gold, nests of native bismuth and ikunolite include abundant maldonite Au₂Bi, an Ag-free mineral. Under conditions of the higher activity of sulfide sulfur, maldonite in gold-bearing hydrotherms is replaced by intergrowths of pure native gold and bismuth, and bismuthinite. The subsequent significant increase in activity of sulfur in gold-bearing hydrotherms led to mass replacement of maldonite by jonassonite. Thus, the direct replacement of maldonite by jonassonite is observed in Darasun ores probably as result of the following reaction: Au₂Bi + 5Bi + 2Bi₂S₃ + S₂ sol → 2AuBi₅S₄. The composition of jonassonite varies from pure AuBi₅S₄, which is most abundant in Darasun ores, to Au(Bi, Pb)₅S₄ with 1–6 wt % Pb, in the case in which galena and bismutoplagionite occur among replaced minerals. Therefore, the jonassonite formula is AuBi₅S₄. Aurostibite pseudomorphs after gold minerals appeared in such ores due to superimposing Sb mineralization with native Sb. Apo-maldonite aurostibite pseudomorphs contain 4–10 wt % Bi. The probable aurostibite–maldonite replacement reaction is as follows: 2Au₂Bi + 6Sb sol + Sb₂S₃ sol → 4Au (Sb, Bi)₂ + (Bi, Sb)₂S₃. Aurostibite contains up to 18 wt % Bi within inner zones of pseudomorphs formed after maldonite decomposition products—pure native gold and bismuth.</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"64 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sulfide Mineralization of Carbonate–Silicate Veins in Early Proterozoic Metabasites of North Karelia: Mineral Assemblages, Mineral Forms of Silver, and Fluid Inclusions","authors":"","doi":"10.1134/s1075701523060107","DOIUrl":"https://doi.org/10.1134/s1075701523060107","url":null,"abstract":"<span> <h3>Abstract</h3> <p>The work presents the first data on sulfide mineralization in carbonate–silicate veins, which are widespread on the islands and coast of the White Sea (North Karelia), associating with Early Proterozoic metamorphosed gabbroid bodies. The veins with Fe–Cu sulfide mineralization up to ore occurrences are localized within metabasite bodies and along their contacts with host gneisses. During the study of the mineral composition of the veins, the main assemblages of sulfide minerals were identified: chalcopyrite –bornite ± chlorite ± selenides and Pb–Ag tellurides (B1); digenite–bornite ± selenides and Pb, Ag, and Pd tellurides (B2); pyrite–bornite ± chalcopyrite (B3); marcasite–pyrite–bornite–chalcopyrite (B4); and siegenite–chalcopyrite ± acanthite ± chlorargyrite. The development of sulfide associations, as well as quartz–chlorite aggregates, was related to the late stage of vein formation. Inductively coupled plasma and laser ablation mass spectrometry analyses showed that bornite from association B1 has the highest silver content (up to 675 ppm) and, in terms of Ag, Se, and Bi contents, is closest to bornite from low-temperature epithermal, skarn, and high-temperature vein deposits. In general, bornite is the main Ag carrier in the studied associations, while digenite containing up to 1000 ppm Ag, as well as discrete silver minerals (selenides, tellurides, acanthite, and chlorargyrite), occur in subordinate quantities. Fluid inclusions in quartz from sulfide associations, as well as from a sulfide-free carbonate–silicate vein, were studied by cryo- and thermometric methods. It is established that mineralization at the late stages of vein formation was related to heterogeneous CO₂–H₂O–NaCl metamorphic fluid. Carbon dioxide fluid inclusions were captured by vein quartz at temperature of 253–314°C and pressure of 2 ± 1 kbar. Water–salt inclusions were captured in a wider temperature range of 100–500°С. The highest temperature fluid inclusions with temperatures of homogenization &gt;300°С are characteristic of quartz veinlets of the siegenite–chalcopyrite association with Ag sulfide and chlorargyrite.</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"254 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139412787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Langbeinite-Group Minerals and Vanthoffite from Fumarole Exhalations of the Tolbachik Volcano (Kamchatka)","authors":"","doi":"10.1134/s1075701523080032","DOIUrl":"https://doi.org/10.1134/s1075701523080032","url":null,"abstract":"<span> <h3>Abstract</h3> <p>In this paper, we provide characteristics of sulfates of exhalation origin—langbeinite K₂Mg₂(SO₄)₃, two modifications of calciolangbeinite K₂Ca₂(SO₄)₃ (new data), and vanthoffite Na₆Mg(SO₄)₄ (first mineralogical data for this genetic type)—from active fumaroles of the Tolbachik volcano in Kamchatka. These minerals are associated with anhydrous copper sulfates and arsenates, minerals of the aphthitalite and alluaudite groups, krasheninnikovite, anhydrite, sanidine, cristobalite, tridymite, tenorite, hematite, etc. Langbeinite and calciolangbeinite form a series of solid solutions, in which most of the compositions correspond to the ranges of (Mg_2.0–1.6Ca_0.0–0.4) and (Ca_1.2–2.0Mg_0.8–0.0). It is shown that, in calciolangbeinite, with a content of more than 20 mol % of K₂Mg₂(SO₄)₃, decomposition into cubic calciolangbeinite with a lower Mg content and langbeinite can occur upon slow cooling. For the first time, in minerals of the langbeinite group, impurities of copper and zinc, the maximal concentrations of which are noted in langbeinite with a low Ca content and reach 0.53 atoms per formula unit (below, apfu) for Zn (10.0 wt % of ZnO) and 0.18 apfu for Cu (3.3 wt % of CuO), were revealed. These elements replace Mg and Ca. Varieties of langbeinite and calciolangbeinite enriched in Na (up to 0.31 apfu = 2.3 wt % of Na₂O) were found. Other significant impurities in these minerals are represented by Rb, Cs, Mn, Cd, Al, and Fe. The fumarole vanthoffite contains impurities of K, Ca, Mn, Zn, Cu, and Fe (up to 0.47 apfu in total). This significant manifestation of cationic isomorphism in langbeinite-group minerals and vanthoffite is observed only at Tolbachik volcano and is caused primarily with the peculiar conditions of their crystallization in high-temperature volcanic fumaroles.</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"19 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aurostibite, Silver-Bearing Gold, and Electrum As a Part of Post-Gold Antimony Mineralization in the Darasun Deposit (Eastern Transbaikalia)","authors":"","doi":"10.1134/s1075701523070115","DOIUrl":"https://doi.org/10.1134/s1075701523070115","url":null,"abstract":"<span> <h3>Abstract</h3> <p>The Late Jurassic orogenic volcanogenic–plutonogenic Darasun gold deposit of the beresite–listvenite gold-sulfide-quartz formation is situated in the Mesozoids of the Eastern Transbaikalian segment of the Mongol–Okhotsk folded belt. The deposit includes Au–Bi and post-gold antimony mineralization. Carbonate–quartz–sulfide veins in the western part of the deposit, composed of gabbroids, gabbro amphibolites, and, to a lesser extent, ultramafic rocks are surrounded by listvenite aureoles. The Au-rich ores were formed under conditions of low activity of sulfide sulfur; they contain pyrrhotite, arsenopyrite, chalcopyrite, bismuthinite, and Pb–Bi sulfosalts associated with a high fineness gold (949–935‰). Aurostibite pseudomorphs after gold minerals have appeared there due to a superimposition of the antimony mineralization with native antimony on gold ores. This aurostibite contains 1.1–1.7 wt % Bi and 0.1–0.3 wt % As, isomorphically replacing Sb. Its composition is Au_{0.998–1.005}(Sb_{1.947–1.965}Bi_{0.024–0.036}As_{0.009–0.017})_{1.995–2.002}, and the average composition is Au_1.001(Sb_1.956Bi_0.031As_0.012)_1.999. Aurostibite does not contain silver. Silver released during the replacement of native gold with aurostibite occurs near its metacrystals in the composition of heterogeneous reaction rims of newly formed gold minerals. They are represented by silver-bearing native gold (fineness 922–712, mostly 919–911) and electrum (fineness 693–584, mostly 625–604). The distribution of the gold fineness in the newly formed minerals of the gold–silver series, as a part of the antimony mineralization, in the volcanogenic–plutonogenic Darasun deposit is very heterogeneous and “irregular.”</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"07 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139755675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogy and Conditions of Formation Genesis of Aggregates of Natural and Sulfide Minerals of the Poldnevskoe Demantoid Deposit (Middle Urals)","authors":"","doi":"10.1134/s1075701523060065","DOIUrl":"https://doi.org/10.1134/s1075701523060065","url":null,"abstract":"<span> <h3>Abstract</h3> <p>Polymineral aggregates of rounded shapes (“nodules”) composed of native and sulfide minerals of Cu, Ni, Fe, Ag, and other elements from vein magnetite–calcite–chrysotile rocks with jewelry demantoid in the Korkodinskoe hypermafic massif are described. A common feature of the six identified types of native sulfide nodules, composed of native copper, heazlewoodite, pentlandite, cuprite, and other native sulfide minerals, is their spheroidal shape, which makes them similar to individual grains of other gangue minerals (calcite, magnetite, etc.). In heazlewoodite–pentlandite nodules, specific symplectites of mercuric silver and nickel copper in heazlewoodite, as well as awaruite in Co–pentlandite, were found. The matching set of ore minerals in the host serpentinite vein mass (native copper, mercuric silver, heazlewoodite, pentlandite, awaruite) and nodules from the vein material indicates their genetic connection and the conjugation of demantoid mineralization with the evolving processes of serpentinization. It was established that the nodules formed at temperatures below 380°C under reducing conditions at very low sulfur fugacity values (10^–17–10^–27 bar) and oxygen (10^–30 bar at 200°C to 10^–21 bar at 350°C). For heazlewoodite–pentlandite nodules, such conditions persisted throughout the entire time of their formation, while, for other nodules, the reducing conditions of early parageneses were replaced by oxidative conditions in late parageneses, which is recorded by the replacement of native copper with cuprite. It is assumed that the features of the morphology and structure of native sulfide nodules and the presence of symplectite intergrowths of ore minerals in them are associated with specific conditions created during the decompression of the crust-mantle mixture rising to the surface in the fault zone. The source of the metals was a deep, high-temperature fluid interacting with mafic and ultramafic rocks under reducing conditions at a low water-to-rock ratio.</p> </span>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"39 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139413397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to: Geochemistry and Petrography of Hydrothermally Altered Rocks of the Ryabinovoe Orefield (Southern Yakutia) as the Basis for the Prediction of Gold–Copper-Porphyry Ore Mineralization","authors":"N. V. Shatova, V. V. Shatov, A. V. Molchanov, O. V. Petrov, A. V. Terekhov, V. N. Belova, V. I. Leontev","doi":"10.1134/s1075701523370018","DOIUrl":"https://doi.org/10.1134/s1075701523370018","url":null,"abstract":"<p>An Erratum to this paper has been published: https://doi.org/10.1134/S1075701523370018</p>","PeriodicalId":12719,"journal":{"name":"Geology of Ore Deposits","volume":"84 1","pages":""},"PeriodicalIF":0.7,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138540829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}