Ore Geology Reviews最新文献

{"title":"MVT-SHMS signature in basement-hosted Zn-Pb-(Cu-Fe) mineralization in the Sila Massif (Calabria, Italy): Evidence from trace elements and fluid inclusions data","authors":"Antonio Ciccolella ,&nbsp;Fabrizio Tursi ,&nbsp;Vincenzo Festa ,&nbsp;Giovanni Ruggieri ,&nbsp;Emanuela Schingaro ,&nbsp;Gennaro Ventruti ,&nbsp;Rosa Anna Fregola","doi":"10.1016/j.oregeorev.2024.106438","DOIUrl":"10.1016/j.oregeorev.2024.106438","url":null,"abstract":"<div><div>Typically, Mississippi Valley Type (MVT) and Sediment-hosted Massive Sulphides (SHMS) Zn-Pb-deposits are hosted by sedimentary basins and are originated from fluids sourced from a crystalline basement. Mixing of fluids from crystalline basement and overlying sedimentary basins, through faults and fractures, is a major trigger for the formation of Zn-Pb deposits. In this context, Zn-Pb mineralization hosted in a crystalline basement and preserving a MVT-SHMS geochemical signature are rarely considered, although found. Here we present the results on a Zn-Pb(−Cu-Fe) mineralization associated to fault zones developed within Permian–Carboniferous intrusive bodies in the northern Sila Massif of Calabria (Italy), at Longobucco (LGB) and Fonte Argentila (FAR) localities. The ore-mineral assemblage consists of sphalerite, galena, ± chalcopyrite, and pyrite. We identified four distinct stages and three generations of sphalerite (Sp1, Sp2, Sp3), characterizing the paragenetic evolution of the mineralization. The Fe-content in sphalerite of LGB and FAR increases from Sp1 (medians of 3.34 and 2.46 wt%) to Sp2 (medians of 6.84 and 7.29 wt%), the latter containing the highest amounts of Cu (up to 1023 ppm), Ga (up to 338 ppm), Ge (up to 400 ppm), and Cd (up to 7589 ppm). Sp3 is characterized by the lowest Fe-content (median of 0.43 wt%) and formed after dissolution-precipitation of the earlier sphalerite generations. Based on the trace element signatures, the LGB-FAR sphalerite formed under low-temperature conditions (medians of 150–183 °C), as indicated by the GGIMFis geothermometer and the Ga/In, In/Ge and Zn/Cd ratios. The geochemical features and the low sulphur fugacity values (log₁₀ƒS₂ = 10^−17.55–10^−17.29 atm) suggest precipitation from an ore-forming fluid of MVT-SHMS/basinal derivation. This model is also supported by fluid inclusions data that record evidence from meteoric to high salinity basinal-type ore-forming fluids trapped within fluorite (T_h = 72.2–114.6 °C; salinities from 0 to 21.2 wt% NaCl eq.). The later ore-forming fluids show meteoric and basinal-type with low to moderate salinity, as evidenced by fluid inclusions trapped within second quartz (Qz2) generation (T_h = 111.6–163.8 °C; salinities of 0.5 to 6.1 wt% NaCl eq.). By comparing our results with those of similar Zn-Pb-deposits, we suggest that the fluids responsible for the peculiar vein-type LGB-FAR mineralization had several characteristics comparable to those related to MVT-SHMS deposits, although we cannot exclude at least an indirect magmatic contribution to the mineralizing fluids.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106438"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mid-Late Jurassic magmatism and its mineralization potential in the Dayaoshan district, southwest Qinhang metallogenic belt, South China","authors":"Xu Wang ,&nbsp;Yu Zhang ,&nbsp;Xia Hu ,&nbsp;Hongjie Shen ,&nbsp;Lianjie Zhao ,&nbsp;Xiyue Zheng ,&nbsp;Shuling Song","doi":"10.1016/j.oregeorev.2024.106429","DOIUrl":"10.1016/j.oregeorev.2024.106429","url":null,"abstract":"<div><div>The Mid-Late Jurassic is a significant period characterized by extensive magmatism and mineralization within the Qinhang metallogenic belt. However, the genesis and metallogenic potential of these Mid-Late Jurassic granitoids in the Dayaoshan district, the southwest part of the Qinhang metallogenic belt, remain inadequately investigated.</div><div>The Dayaoshan Mid-Late Jurassic granitoids primarily comprise the Fuqing granodiorite (161.5 ± 3.2 Ma), Dabang granodiorite (157.4 ± 2.4 Ma), Dabang granodiorite porphyry (155.9 ± 2.8 Ma), Shangdong granodiorite (153.7 ± 2.8 Ma), Fenghuang granodiorite (162.6 ± 1.1 Ma), and Yuanzhuding granite porphyry (154.3 ± 1.7 Ma). These rocks exhibit typical I-type affinity, marked by lower A/CNK values (0.9–1.1) and the presence of magnetite. Whole-rock Nb/Ta ratios (9.0–14.0), biotite major elements, apatite trace elements, Mg^# value (35–63), and zircon ε_Hf(t) (–19.7–4.2) and T_DM2 (2440–834 Ma) indicate that the Dayaoshan Mid-Late Jurassic granitoids likely originated from remelting Precambrian metamorphic crustal material with some mantle material inputting. The higher Mg^# value (52–63) and more positive ε_Hf(t) value (–6.3–4.2) of the Yuanzhuding granite porphyry, genetically associated with porphyry Cu-Mo mineralization, suggest it contains more mantle-derived material compared to other granitoids. Regarding magma evolution, apatite and/or whole-rock trace elements show that the Fuqing granodiorite is dominated by amphibole fractionation, while the Dabang granodiorite, Dabang granodiorite porphyry, and Shangdong granodiorite are characterized by plagioclase fractionation. Based on the existing research on the Mid-Late Jurassic tectonic-magmatic activities in the Qinghang metallogenic belt, it is inferred that the Dayaoshan Mid-Late Jurassic granitoids are products of asthenospheric upwelling caused by the subduction of the Paleo-Pacific plate. The Dayaoshan Mid-Late Jurassic granitoids, excluding the Yuanzhuding granite porphyry, generally exhibit characteristics of low differentiation, low oxygen fugacity, and crust-mantle mixed source, thereby excluding the possibility of associated W-Sn and Cu mineralization. The mineralization age (Mid-Late Jurassic) along with S–Pb–H–O isotope compositions of lode gold deposits in the Dayaoshan region support their genetic linkage with the Mid-Late Jurassic magmatism, consistent with high water and gold content and low differentiation of the Dayaoshan Mid-Late Jurassic granitoids (except Yuanzhuding). This research highlights a good prospect for lode gold deposits around the Mid-Late Jurassic granitoids in Dayaoshan.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106429"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Al3+ on thermochemical sulphate reduction (TSR) at 250°C to 350°C under vapour-saturated pressures: A Raman spectroscopic investigation","authors":"Yun-He Zhou ,&nbsp;Lin-Bo Shang ,&nbsp;I-Ming Chou ,&nbsp;Chen Chen ,&nbsp;Zi-Qi Jiang ,&nbsp;Xin-Song Wang ,&nbsp;Jian-Guo Li","doi":"10.1016/j.oregeorev.2024.106413","DOIUrl":"10.1016/j.oregeorev.2024.106413","url":null,"abstract":"<div><div>In geological processes, thermochemical sulphate reduction (TSR) is a significant way to transform oxidising sulphur into reducing sulphur, such as H₂S, that can promote the formation of metal sulphide deposits. The occurrence of TSR is a complex process, where all kinds of sulphate, organic matter, and catalysis materials are involved, in which Al exists commonly in geological background. In order to figure out the function of Al in the TSR process, a series of experiments were conducted to investigate the TSR by using fused silica capillary capsules combined with Raman spectroscopy at temperatures ranging from 250°C to 350°C in this study. Ethanol (cracked into ethylene by heating) or acetic acid was used as reducing agents, and sodium sulphate or magnesium sulphate as oxidising agents, and the AlCl₃ was introduced as a variable to investigate its effect on the initiation of TSR. Raman spectra were collected from the quenched and in-situ experiments. The results indicate that the addition of AlCl₃ favours the initiation of TSR. In-situ Raman investigation reveals that HSO₄^- is the dominant sulphate species involved in TSR under our experimental conditions. This facilitating effect of AlCl₃ on TSR has been attributed to the increased acidity in solution caused by the release of H⁺ through the formation of Al³⁺-bearing minerals such as natroalunite, where the released H⁺ combines with SO₄^2- to form HSO₄^-. And SO₂ was detected as an intermediate product during the reduction of HSO₄^- by in situ Raman spectroscopy. The experimental results imply that it is possible that the TSR can occur and accumulate enough reduced sulphur in a short period of time in an aluminium-rich geological environment at temperatures as low as 250°C.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106413"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constraints of reducing media on uranium mineralization in the uranium-bearing rock systems of the southern Songliao Basin","authors":"Qingshuang Wang ,&nbsp;Hu Peng ,&nbsp;Chao Liu ,&nbsp;Zhongyue Zhang ,&nbsp;Yongheng Zhou ,&nbsp;Xiaodan Guo ,&nbsp;Nan Ju ,&nbsp;QiuLin Fu ,&nbsp;Yan Hao","doi":"10.1016/j.oregeorev.2024.106406","DOIUrl":"10.1016/j.oregeorev.2024.106406","url":null,"abstract":"<div><div>The southern Songliao Basin harbors uranium-bearing rock series characterized by two distinct sedimentary environments: humid and arid, each displaying marked variations in the abundance of reducing agents and the spatial distribution of uranium mineralization. This comprehensive study meticulously delves into the petrology, mineralogy, and petrogeochemistry of the Lower Cretaceous Fuxin Formation (humid environment) and the Upper Cretaceous Quantou and Yaojia Formations (arid environment). Within these uranium-rich rock series, uranium minerals predominantly reside within coarse clastic rocks, particularly occupying interstitial spaces between clastic particles and their edges, with minor occurrences within mineral interiors or adsorbed on surfaces. Notably, the Fuxin Formation stands out for its stronger association of uranium minerals with carbonaceous detritus and pyrite. The unusually abundant internal reducing agents, like carbonaceous detritus and pyrite, within the Fuxin Formation’s uranium-bearing rocks, impede the development of interlayer oxidation zones, resulting in uranium mineralization concentrated near basin margins. Conversely, the Quantou and Yaojia Formations exhibit a relative paucity of internal reducing agents, while external sources like coal seams and hydrocarbon reservoirs accumulate centrally within the basin. This configuration promotes the extensive spread of interlayer oxidation zones and uranium mineralization deep into the basin’s interior. In essence, the abundance and spatial distribution of reducing agents determine the extent and pattern of interlayer oxidation zones and uranium mineralization. Both internal and external reducing agents intricately interact to orchestrate the uranium mineralization processes.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106406"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid evolution and physicochemical constraints of the Nasigatu greisen-type Be deposit in Inner Mongolia","authors":"Xue Wang ,&nbsp;Ke-yong Wang ,&nbsp;Wen-chun Ge ,&nbsp;Hao Yang ,&nbsp;Hao-ran Wu ,&nbsp;Jun-chi Chen","doi":"10.1016/j.oregeorev.2024.106431","DOIUrl":"10.1016/j.oregeorev.2024.106431","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The Nasigatu greisen-type beryllium (Be) deposit, located at the western slope of the southern Great Xing’an Range (GXR), within the Central Asian Orogenic Belt (CAOB), exhibits a complex ore-forming history involving both magmatic and hydrothermal processes. The deposit consists of lenticular or vein-shaped orebodies hosted in alkali-feldspar granite, and two types of mineralization are observed: disseminated beryl mineralization in greisen and quartz–beryl vein mineralization cutting through the greisen or into surrounding rocks. The entire ore-forming process can be divided into two periods: magmatic (alkali-feldspar granite, M&lt;sub&gt;I&lt;/sub&gt;) and hydrothermal (I–IV) periods. The hydrothermal period is divided into four stages according to its mineral assemblage characteristics: (I) greisen, (II) quartz–muscovite–beryl ± fluorite veins in greisen, (III) quartz–beryl ± phenakite ± fluorite pegmatite veins, and (IV) quartz–fluorite veins.&lt;/div&gt;&lt;div&gt;Melt inclusion (M−type), vapour-rich two-phase aqueous (LV-type), pure vapour (V-type), and daughter mineral-bearing three-phase (SVL-type) fluid inclusions (FIs) are developed in M&lt;sub&gt;I&lt;/sub&gt; quartz, and the coexistence of melt inclusions and brine fluids indicates that they are captured in the magmatic-hydrothermal transition stage. At stage I, liquid-rich two-phase aqueous (VL-type), V-, LV-, and SVL-type FIs (525–585 °C, 6.0–42.7 wt% NaCl eqv) existed, and VL-type FIs exhibited a relatively high vapour/liquid ratio, ranging from 30 % to 40 %. From stage Ⅱ to stage IV, only VL-type FIs existed, with temperatures of 336–395, 287–326, and 180–225 °C and salinities of 6.6–8.5, 5.8–8.0, and 4.6–5.8 wt% NaCl eqv, respectively. The isotopic data (H-O) indicate that the ore-forming fluid initially consisted of magmatic water, which later interacted with meteoric water. Based on P-T diagrams and the physicochemical conditions delineated by the logaSiO&lt;sub&gt;2&lt;/sub&gt;–logaAl&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; and µHF–µKF relationships, the mineralization of the Be deposit is estimated to have occurred within a pressure–temperature regime of 50–210 MPa and 308–585 °C. In contrast, the P-T conditions required for pegmatite vein formation were relatively lower. Furthermore, the formation of phenakite demands lower activities of SiO&lt;sub&gt;2&lt;/sub&gt; and Al&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; and higher HF activity compared to beryl. The elevated HF activity suggests that phenakite crystallization is favored in a relatively more acidic environment, which is consistent with the fluid’s increasing fluorine concentration during the later stages of mineralization.&lt;/div&gt;&lt;div&gt;It can be concluded that the initial ore-forming fluid evolved following the intrusion of Early Cretaceous magmatic rocks, with the fluid being directly derived from the crystallizing silicate melt under conditions characteristic of a two-phase zone. Beryllium (Be) became concentrated in the residual magma during the crystallization of alkali-feldspar granite. As temp","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106431"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geophysical exploration of the giant Bayan Obo REE–Nb–Fe deposit in Inner Mongolia, China: Progress and challenges","authors":"Wei-Ying Chen ,&nbsp;Guo-Qiang Xue ,&nbsp;Ya Xu ,&nbsp;Jian Wang ,&nbsp;Peng-Fei Lv ,&nbsp;Xin Wu ,&nbsp;Wan-Ting Song ,&nbsp;Hong-Rui Fan ,&nbsp;Yong-Gang Zhao ,&nbsp;Xian-Hua Li","doi":"10.1016/j.oregeorev.2024.106415","DOIUrl":"10.1016/j.oregeorev.2024.106415","url":null,"abstract":"<div><div>The Bayan Obo giant rare earth element (REE)–niobium (Nb)–iron (Fe) deposit, located in Inner Mongolia, is recognized globally as a significant comprehensive deposit and serves as a crucial rare resource base in China. Despite nearly seven decades of mining operations, numerous scientific questions pertaining to the Bayan Obo deposit remain unanswered, underscoring an urgent necessity to assess the quantities of rare resources and to explore alternative sources of iron ore. Addressing these issues is intrinsically connected to geophysical exploration efforts. In the past decade, extensive geophysical investigations have been conducted in the Bayan Obo mining region, resulting in substantial evidence that enhances the understanding of the deposit’s characteristics. However, practical exploration has demonstrated that the complex nature of the exploration targets, coupled with the environmental conditions in the Bayan Obo mining area, poses significant challenges to various geophysical exploration initiatives. This paper primarily reviews the advancements and achievements in geophysical exploration within the Bayan Obo mining area over the past ten years, while also examining the key challenges faced during these exploration efforts. Finally, several critical directions for future geophysical exploration activities are proposed.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106415"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical footprints of peraluminous rare-metal granites and pegmatites in the northern French Massif Central and implications for exploration targeting","authors":"Matthieu Harlaux ,&nbsp;Olivier Blein ,&nbsp;Christophe Ballouard ,&nbsp;Daniel J. Kontak ,&nbsp;Denis Thiéblemont ,&nbsp;Anne Dabosville ,&nbsp;Blandine Gourcerol","doi":"10.1016/j.oregeorev.2024.106409","DOIUrl":"10.1016/j.oregeorev.2024.106409","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Peraluminous rare-metal granites and pegmatites (RMGP) formed in late-orogenic settings represent an important source of elements essential to the energy transition and the electronics industry, such as Li, Ta, Nb and Sn. However, exploration for RMGP in crystalline basement is hampered by their typically small size, lack of distinctive petrophysical characteristics, and proximity with earlier, larger barren composite granitic plutons that may mask their presence. This paper reviews the main geochemical features of late-Variscan, 315-to-310 Ma RMGP in the northern French Massif Central (FMC) to better define useful geochemical proxies relevant to exploration targeting. The northern FMC defines a ca. 150 km-long metallogenic province that hosts three types of RMGP: (i) the Beauvoir and Montebras leucogranites, (ii) the Chédeville pegmatite field, and (iii) the Richemont rhyolite. Based on a compilation of whole-rock geochemical data for these RMGP (n = 151) and other late-Variscan peraluminous granites in the FMC (n = 1953), we examine the enrichment of rare elements (Li, F, Be, Nb, Ta, Sn, W) as well as indices of magmatic fractionation and hydrothermal alteration in these settings. The RMGP are variably enriched in Li (372–11,200 ppm; avg = 3500 ppm), F (1475–40,000 ppm; avg = 15,010 ppm), Be (3–506 ppm; avg = 107 ppm), Nb (25–200 ppm; avg = 79 ppm), Ta (23–447 ppm; avg = 116 ppm), Sn (19–13,311 ppm; avg = 1069 ppm) and W (3–312 ppm; avg = 38 ppm), of which the Beauvoir leucogranite is the most enriched. Compared to the peraluminous cordierite-biotite and two-mica granites in the FMC, the RMGP are strongly fractionated with very low Σ(Fe + Mg + Ti), low Nb/Ta (&lt;2), Zr/Hf (&lt;20) and Th/U (&lt;1) ratios, and high Rb/Sr ratios (&gt;10). In addition to these striking features, the RMGP show a systematic spatial association with evolved two-mica granites containing elevated contents of Li (avg = 627 ppm), F (avg = 4462 ppm), Be (avg = 28 ppm), Nb (avg = 32 ppm), Ta (avg = 14 ppm), Sn (avg = 122 ppm) and W (avg = 19 ppm), which are 2–4 times higher relative to other peraluminous two-mica granites in the FMC. The emplacement of these evolved granites was synchronous with magmatism at ca. 330–315 Ma, preceding and partly overlapping the formation of RMGP. Interpolated element distribution maps from the studied areas show large geochemical halos for Li, Be, F and Sn (±W) around the granites spatially associated to RMGP, with concentrations exceeding ten times upper continental crust values, and extending several km from the plutons. Due to their highly-evolved character and large geochemical footprints (&gt;10 s km&lt;sup&gt;2&lt;/sup&gt;), the granitic plutons associated with RMGP represent pre-enriched, specialized precursors for rare-metal mineralization. Given the regional extent of evolved peraluminous leucogranites in the northern FMC, we conclude that there is a significant mineral potential for rare metals (especially Li) and that future geoch","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106409"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The origin and role of CH4–N2 in the formation of Yantongqiaozi gold deposit, Jilin Province, NE China","authors":"He Yang ,&nbsp;Shunda Li ,&nbsp;Bingyang Ye ,&nbsp;Keyong Wang","doi":"10.1016/j.oregeorev.2024.106434","DOIUrl":"10.1016/j.oregeorev.2024.106434","url":null,"abstract":"<div><div>The Yantongqiaozi gold deposit, located in the southern Jilin Province of Northeast China, is hosted within a breccia pipe and surrounded by Archean metamorphic rocks. This deposit has four paragenetic stages: stage I pyrrhotite–pyrite–quartz, stage II gold–pyrite–quartz, stage III sphalerite–pyrite–quartz, and stage IV pyrite–quartz–calcite. Additionally, it contains CH₄–N₂-rich fluid, which is associated with gold mineralization; however, the origin and evolution of this fluid remains unclear. Fluid inclusion petrography and microthermometry revealed that stage I is characterized by medium–high temperature CH₄–H₂O fluids (296–359 °C), which evolves into medium-temperature N₂–CO₂–H₂O fluids (251–323 °C) in stage II, further shifting into low-temperature NaCl–H₂O fluids (165–254 °C) in stages III and IV. The H–O–C–N isotopes record that the initial magma fluids were contaminated by organic matter from the surrounding strata, followed by water–rock interaction and gradual dilution by meteoric water. CH₄ in the stage I fluid is generated by the thermal decomposition of organic matter, possibly from Jurassic coal-bearing strata. CH₄-rich fluids facilitate the activation and migration of gold from the surrounding strata. The simultaneous trapping of single-phase CH₄ and H₂O inclusions indicate that fluid effervescence is the primary mechanism of metal precipitation in stage I. The conversion of CH₄ to CO₂ in stage II fluid is indicative of increased oxygen fugacity. N₂, likely owing to the breakdown of NH₄⁺-containing minerals formed during metamorphism. Isotopic fractionation patterns suggest that extensive water–rock interactions lead to gold precipitation in stage II. Substantial temperature decreases and volatile losses in the stage III and IV fluids indicate continuous dilution by meteoric water, resulting in mineral precipitation. Unlike that in reduced porphyry and orogenic gold deposits, the gold mineralization at Yantongqiaozi derives from the combined effects of magmatic and metamorphic processes. Together, our findings highlight the pivotal role of CH₄–N₂-rich fluids in the migration and precipitation of gold and support a porphyry–orogenic transitional mineralization model for the Yantongqiaozi deposit. This model is expected to provide insights regarding the genesis and exploration of similar deposits.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106434"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of the Dongjiahe Zn-Pb deposit, South China: Implication for exploration of Mississippi Valley-type ore in Marinoan cap dolostone","authors":"Liangliang Zhuang,&nbsp;Yucai Song,&nbsp;Jiahui Ren,&nbsp;Zhiyi Wu","doi":"10.1016/j.oregeorev.2025.106442","DOIUrl":"10.1016/j.oregeorev.2025.106442","url":null,"abstract":"<div><div>The Marinoan cap dolostone overlying the Marinoan glacial deposits (∼650–635 Ma) occurs on almost every continent and shows similar sedimentary structures in all cases. Insights from this study of the cap dolostone-hosted Dongjiahe Mississippi Valley-type (MVT) Zn-Pb deposit, South China, might improve exploration strategies for MVT ore in this unit. The Dongjiahe cap dolostone includes three lithological units in an anticline. The basal and upper units, respectively 1–2 m thick, host Zn-Pb ore. The basal unit develops sheet cracks and breccias, associated with pre-ore dolomite and chalcedony cementation. The dolomite cement is inconsistent in C-O isotopes relative to the neighboring dolostone, indicating the post-depositional cementation. The dolomite and chalcedony alteration created open spaces that were filled by sphalerite and galena. The upper unit of dolostone is laminated and fine crystalline. Folding-related bedding-parallel and −oblique fractures in the unit were filled by pre-ore chalcedony and then by Zn and Pb sulfides. The distribution of ore within the Dongjiahe anticline indicates that the axial zones of anticlines and associated second-order anticlines are favorable locations for fracture generation and mineralization. Therefore, exploration of MVT ore in Marinoan cap dolostones needs to understand the development and distribution of open spaces created by pre-ore mineral alteration and regional folding deformation. In addition, the presence of bitumen indicates that the cap dolostone unit at the Dongjiahe deposit was a hydrocarbon trap that might have played a role in the generation of reduced sulfur that contributed to the Zn-Pb mineralization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106442"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"U-Pb dating, mineral geochemistry and sulfur isotopes of the Tieshan complex in Fujian Province, southeast China: Implications for Pb-Zn polymetallic mineralization","authors":"Xiaoyu Shang ,&nbsp;Minfang Wang ,&nbsp;Fan Xiao ,&nbsp;Xiangyi Ji ,&nbsp;Ruizhe Zhao","doi":"10.1016/j.oregeorev.2024.106425","DOIUrl":"10.1016/j.oregeorev.2024.106425","url":null,"abstract":"<div><div>The Tieshan complex is located in Zhenghe area of Fujian Province (SE China), which is potassic altered with extensive Cu-Mo-Au-Pb-Zn polymetallic mineralization. U-Pb dating of zircon from granite (171.38 ± 0.55 Ma) and garnet from Pb-Zn skarn ore (176.4 ± 2.1 Ma) suggested that the magmatism occurred during the Jurassic Yanshanian orogenic event. The age of magmatic apatite from granite (196.7 ± 4.1 Ma) was older than the ore formation age. The hydrothermal apatite has higher Th-Sr-V-As-U-Pb but lower Rb-Ti-Mn contents than the magmatic apatite. The elevated positive Eu and Ce anomalies, low Ce/Y and Mn/Fe but high Sr/Y ratios in the hydrothermal apatite suggested a more oxidizing mineral-forming environment. In-situ sulfur isotopes in sulfides (−0.58 to −4.57 ‰) show a deep fluid source, and the magmatic-hydrothermal fluid may have reacted with crustal rocks and mixed with meteoric water. We suggest Pb-Zn exploration potential at depth near the Jurassic (176–171 Ma) plutons at Zhenghe.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"176 ","pages":"Article 106425"},"PeriodicalIF":3.2,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143139186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}