Polymetallic Sulfide Research Articles

Cross‐Scale Synergistic Manipulation of Dielectric Genes in Polymetallic Sulfides from Micropolarization to Macroconductance Toward Wide‐Band Microwave Absorption

AbstractRecently, the design and development of efficient microwave absorbents by facile engineering approaches have attracted much attention. Particularly, some unique structures caused by cross‐scale design are promising in enhancing the absorbing capability toward microwave irradiation. Herein, the cross‐scale design strategy is implemented to enhance the electromagnetic wave absorption performance of polymetallic sulfides (PMS). In PMS, the dipole polarization unit is optimized, and the distribution of electronic states is improved by doping Ti atoms; Meanwhile, the MS/M3S4 homogeneous hetero‐phases interfaces is constructed in PMS using a phase separation strategy; and the conductivity of PMS is modulated by the addition of acetylene black (ACET). The cross‐scale synergy of microwave absorption leads to a significant enhancement of the microwave absorption (MA) performance of PMS/ACET composites. The optimal reflection loss value of Ti‐LES with 10% ACET addition reaches −55.49 dB and the effective absorption bandwidth reaches 6.73 GHz. The 17.5% ACET‐conditioned Ti‐HES achieves a reflection loss of −37.2 dB at a low frequency of 4.8 GHz. This study not only provides a novel strategy for the development of new broadband MA materials but also validates a new idea for the multi‐scale synergistic optimization of MA materials.

Exploration of hydrothermal venting sites using deep-towed multibeam echosounder data

The Federal Institute for Geosciences and Natural Resources (BGR) obtained a contract for the exploration of polymetallic sulphides from the International Seabed Authority (ISA) in an area of 10,000 km2 located in the southwestern Indian Ocean. Since obtaining this contract of exploration in 2015, BGR has conducted annual research cruises to this area and continuously improves the exploration methods for seafloor sulphides deposits. One of the main instruments is HOMESIDE, a deep-towed multibeam echo sounder (MBES) sled. Its water column data allows to visualize and therefore locate discharge sites of hydrothermal fluid – active hydrothermal venting sites (or commonly also referred to as “black smokers”). Additionally, its bathymetric data is used for geological mapping and therefore greater analysis of the seafloor geomorphology. HOMESIDE is typically towed at an altitude of about 100 m above the seabed in a water depth of approximately 3,000 m, allowing a resolution of the derived digital terrain model (DTM) of 2 m. Due to malfunction of individual positioning sensors or operational errors, the navigation data might need to be further corrected in post-processing. Navigation offsets between adjacent lines are mostly apparent in overlapping swath data. The tool mbnavadjust of the open-source software MB-System showed to be a valuable tool to improve the data quality subsequently in areas with data overlap and systematic navigation offsets. Data mismatches of more than 10 m are processed with this tool and can, therefore, be reduced significantly. In this paper, firstly, the role of deep-towed MBES as exploration tool for hydrothermal sites is presented. Secondly, the importance of post-processing MBES navigation based on the swath data especially for this project is highlighted. The workflow as well as the results are presented and show significant improvement.

Selective leaching of lead from complex polymetallic sulfide secondary concentrate with ferric methanesulfonate and methanesulfonic acid solution

The selective leaching of lead from complex polymetallic sulfide secondary concentrate (CPSSC) with the solution mixed by ferric methanesulfonate and methanesulfonic acid (Fe(MS)3-MSA) was investigated by leaching experiments, analysis of solids, and electrochemical characterizations. The leaching results showed that stirring rate, liquid–solid ratio, temperature, and ferric concentration greatly influenced Pb extraction rate. At the optimum leaching conditions, 93.1 % Pb, while 3.8 % Cu and 18.8 % Fe were extracted. The selective leaching mechanism was related to the activity of PbS in Fe(MS)3-MSA solution and the galvanic effect between sulfides. XRD and SEM-EDS results of leaching residues verified the selective decreases in PbS, and retainment of most Cu, Fe, and Zn. Electrochemical characterizations demonstrated a more stable and higher open-circuit potential, and an increase/decrease in A0 peak potential/current in LSV curve for the residue’s electrode, suggesting the selective decreases in active components (e.g. PbS). After selective leaching, Cu could be easily extracted from residues by pressurized water leaching, and Fe(MS)3-MSA solution could be regenerated for recycling used in leaching. These results indicate the great potential of Fe(MS)3-MSA solution to selectively leach and separate Pb from CPSSC, and unveil a method to effectively treat refractory CPSSC.

Rb–Sr Pyrite Dating and S–Pb Isotopes in the Fang’an Gold Deposit, Wuhe Area, Eastern Anhui Province

The Fang’an gold deposit in the Wuhe area, Anhui Province, is located in the area adjacent to the Bengbu Uplift and Wuhe Platform Depression in the southeastern part of North China. This study aimed to determine the deposit’s mineralization age and the source of its metallogenic materials and mineralization processes through investigations into its geological characteristics, Rb–Sr isotopes, and S–Pb isotopes. The orebodies of the Fang’an gold deposit in the Neoarchean Xigudui Formation primarily exhibit a vein-type structure. The ore-forming process can be divided into four stages: (i) the quartz stage (Py1); (ii) the quartz–pyrite stage (Py2); (iii) the polymetallic sulfide stage (Py3); and (iv) the carbonate stage. Of these, the main mineralization stage is also the main period in which gold mineralization occurs. In situ sulfur isotope results of pyrite (Py1 to Py3) in the first three mineralization stages, suggesting a contribution of sulfur from crust–mantle magmatic fluids. The δ34S values for Py2 (average 5.51‰) are higher than Py1 (average 4.45‰) and showed that the magmatic fluids mixed with meteoric waters. The δ34S values for Py3 (average 5.18‰) are lower than Py2 (average 5.51‰), revealing that it related fluid immiscibility. The lead isotopic compositions of sulfides within the ores possessed 206Pb/204Pb ratios ranging from 16.759 to 16.93, 207Pb/204Pb ratios ranging from 15.311 to 15.402, and 208Pb/204Pb ratios ranging from 37.158 to 37.548. These lead data were plotted close to the Xigudui Formation, relatively distant from the Mesozoic granites, indicating that the Xigudui Formation was the source of lead for the Late Mesozoic ores of the deposit. Taken together, due to the degassing of mantle-derived magma in the shallow parts of the crust, it can be determined that the sources of ore-forming sulfur and lead were crust–mantle magmatic activities in the Wuhe area. Rb–Sr dating of pyrite from Fang’an gold deposit reveals that the mineralization occurred at 126.89 ± 0.58 Ma. Considering the previous research into the dating of magmatic rocks in the Wuhe area, we propose that the genesis of the Fang’an gold deposit is closely associated with magmatic activities in the area at around 130 Ma.

Ore-forming material sources of the Pakbeng gold deposit, Laos: Evidence from fluid inclusions, H-O-S isotopes, and trace elements

The Pakbeng gold deposit, located at the junction of the eastern Tethys and western Pacific tectonic domains, is part of the Phôngsali-Luang Prabang-Sayaboury polymetallic metallogenic belt. Its gold ore bodies are predominantly governed by fault structures, being vein-like and short-axis-veined in shape. The Pakbeng gold deposit primarily exhibits two types of mineralized alterations: the quartz-vein type and the schistositized altered rock type. The ore bodies are primarily distributed within cataclastic granites and altered andesite plutons, near their contact zone. The ore-forming process can be divided into four stages: quartz + rutile + pyrite (stage I), quartz + pyrite + coarse-grained arsenopyrite (stage II), quartz + polymetallic sulfides + native gold (stage III), and calcite + quartz (stage IV). Native gold primarily occurs as invisible gold in the quartz and pyrite of stages I and II, and as enclosed, intergranular, and interstitial gold within the quartz, pyrite, and other metal sulfides of stage III. The ore-forming materials of the Pakbeng gold deposit primarily originate from plagioclase granites and altered andesites, as indicated by investigations of gold-bearing quartz fluid inclusions, hydrogen and oxygen isotopes, the trace-element composition of pyrite, and in situ sulfur isotopes. The sulfur in the deposit is mainly derived from metamorphic sources, supplemented by late magmatic sulfur. The ore-forming fluids in the deposit were dominated by metamorphic fluids in the early stage, with magmatic fluids participating in the late stage. While ascending, the temperature of the ore-forming fluids decreased due to fluid boiling and mixing, but their salinity increased slightly. The ore-forming fluids exhibited a consistent decrease in homogenization temperatures from stages I to IV, with salinity initially increasing and then decreasing. This suggests that the ore-forming fluids are low-temperature, medium to low-salinity and low-density fluids.

Chemical constituents and chemotaxonomic research of the deep-sea-derived fungus Aspergillus japonicus W6

Aspergillus japonicus was isolated from polymetallic sulfide thulium deposits in the South Atlantic. A systematic investigation on its secondary metabolites led to the isolation of one new (1) and 23 known (2–24) compounds. Mainly by detailed analysis of the NMR and HRESIMS spectroscopic data, DP4+ probability, as well as calculated ECD spectra, the absolute configuration of 1 was finally determined to be (3S,5R,7R,9R,11S) methyl-3,5,9-trihydroxy-7,11-epoxytetradecanoate. Compound 1 could be used as chemotaxonomic marker of A. japonicus W6 to distinguish the other A. japonicus.

Enhancing photocatalytic performance of Cu6Fe2SnS8 by N doping using magnetic grinding method

Nitrogen doped quaternary metal sulfide Cu6Fe2SnS8 (CFTS) was prepared by magnetic grinding. The mechanochemical method has the advantage of simple synthesis of non-metallic doped polymetallic sulfides, and there is no solvent involved in the reaction process, which is very environmentally friendly. Non metallic doping can form electron capture centers on semiconductors, suppress the recombination of photo generated electron hole pairs, and extend electron lifetime. Moreover, doping N element into the CFTS lattice will lead to the formation of new energy states, thereby narrowing the energy band gap. The characterizations of XPS and EDS have proven the successful doping of N element into CFTS. In addition, the photocatalytic mechanism and the stability of the N-doped CFTS (N-CFTS) were studied through active substance capture experiments and cyclic experiments. The experimental results indicate that ·O2− is the main active substance in the degradation of MB by N-CFTS. After multiple cyclic experiment, the N-CFTS catalytic material still exhibits good crystal structure and photocatalytic stability. This photocatalytic material has great potential for applications in wastewater treatment and environmental remediation.

Co enrichment and Au–Cu–Co association in the Yundukala deposit in East Junggar, NW China: An in situ LA-ICP-MS study

The Yundukala deposit is a newly discovered Au–Cu–Co deposit located in the northern margin of Junggar in the Central Asian Orogenic Belt. The Au–Cu–Co mineralization is associated with the contact zone between a dioritic intrusion and basalt. The formation of the vein mineralization can be divided into three mineralization stages: chlorite + pyrite, quartz + polymetallic sulfide, and quartz + calcite. Ore microscopy and in-situ laser ablation inductively coupled plasma mass spectrometry were used to investigate textural and compositional relationship between pyrite, chalcopyrite, arsenopyrite, and cobaltite. The gold in the deposit is present in two main mineralogical forms: native gold (micron inclusions of the gold) and invisible gold (solid solution of gold). Cobalt in the vein mineralization is primarily associated with cobaltite, whereas pyrite, chalcopyrite, arsenopyrite, and pyrrhotite contain small amounts of cobalt. There is a positive correlation between As and Au in Py-Ⅱ (R2Au-As = 0.9211; R2Au-As = 0.4306) and cobaltite and a positive correlation between Co and Au in cobaltite (R2Au-Co = 0.8168). This relationship supports a model in which arsenic plays a role in the occurrence of gold. The correlation of trace elements in minerals and the formation sequence and interpenetration relationship between minerals indicate the progressive geochemical evolution of a single ore-forming fluid arising from a single vein mineralizing event. Hydrothermal processes led to alteration of the surrounding rocks while simultaneously extracting Au, Cu, and Co, forming ore-forming fluids. As physical conditions changed, minerals began to precipitate, ultimately resulting in the formation of ore deposits during the Carboniferous period (354–353 Ma).

Characterization of deep ore-forming fluid in the Zhaoxian gold deposit within the Jiaodong gold province: insights from quartz vein fluid inclusion, in-situ trace element analysis, and S isotopic composition in pyrite

The Jiaodong gold province, situated in the southeastern margin of the North China Craton, is globally renowned for its substantial gold reserves exceeding 5,000 tonnes. The Zhaoxian gold deposit is part of the significant Jiaojia gold belt within the Jiaodong gold province. Fieldwork has identified four distinct stages of ore formation in this study: an early barren quartz vein stage (Stage 1) containing fine-grained pyrite; a gold-bearing stage (Stage 2) consisting of quartz, pyrite, and native gold; a polymetallic sulfide-rich stage (Stage 3) comprising quartz, polymetallic sulfides, and native gold; and a late-stage (Stage 4) primarily composed of quartz and calcite with minimal pyrite content. We conducted fluid inclusion analysis using microthermometry and Raman spectroscopy techniques to examine the fluid characteristics. In-situ analysis of trace elements in pyrite was performed to investigate the fluid composition and evolution. Additionally, we determined the sulfur isotope composition in pyrite to analyze the source of sulfur. Our findings indicate that the ore-forming fluid in the Zhaoxian gold deposit belongs to a medium-to-low-salinity H₂O-NaCl-CO₂-CH₄ system. Fluctuations in Au and As concentrations observed along with oscillating zones and sulfide inclusions during Stage 2 suggest potential fluid boiling processes occurring during mineralization. High concentrations of Ag, Cu, Zn, Cd, In, Pb, and Bi without oscillating zones during Stage 3 imply precipitation of polymetallic sulfides under stable fluid conditions. The δ34S values observed in the Zhaoxian gold deposit are slightly higher than those found in granitoids from other areas within Jiaodong but similar to those seen in other deposits within the Jiaojia gold belt region. In conclusion, magmatic-hydrothermal ore-forming fluids were involved along with significant fluid-rock interaction during metallogenic processes of the Zhaoxian gold deposit.

The base metal sulfide and Ni–Co arsenide-bearing veins of Valsassina, Lombardy, Italy: a preliminary study

Abstract Valsassina (Lombardy, Northern Italy) is located in the Lombard Southern Alps and is characterised by the presence of a metamorphic basement, by a major late Variscan intrusive complex and by Carboniferous–Permian volcano-sedimentary cover units. These rocks host a pervasive system of inadequately studied mineralised veins. These veins are characterised by base metal (Pb, Zn, Cu and Fe) and complex polymetallic assemblages. In this study, we have investigated the ore textures, mineral compositions of sulfides and sulfosalts (by EMPA–WDS and LA–ICP–MS analyses), and stable isotopes (C and O) in carbonate gangue minerals of various mineralised veins to determine the conditions of deposition of these ore deposits. Two different vein families can be recognised in Valsassina: NNW–SSE veins characterised by a complex polymetallic sulfide–sulfosalt assemblage, also with Ni–Co–Fe arsenides and other Ag–Bi-bearing minerals; and NE–SW veins with a simpler, base metal sulfide assemblage. The Ni–Co-bearing NNW–SSE veins have some distinctive features of the ‘five-element vein’ type deposits, with the Ni–Co–Fe arsenide ore stage pre-dating a sulfide-tetrahedrite-dominated ore stage. LA–ICP–MS data for pyrite and sphalerite, and stable isotopic compositions (C and O) of the carbonate gangue minerals, show no clear differences between the two families of veins, which are probably linked genetically. The isotopic compositions of the Valsassina vein carbonates are closely comparable with the signature of several major five-element ore districts. Preliminary temperature estimates for the Valsassina vein systems were based on the sphalerite composition, applying the GGIMFis geothermometer. The estimated temperatures for the sulfide-dominated ore stage post-dating the Ni–Co minerals precipitation range between 100 and 250°C. The crosscutting relationships, observed for all the veins with the host rocks, suggest a possible late to post Variscan (late Permian) age, making these vein systems comparable with other late–post Variscan polyphase hydrothermal events affecting large sectors of the Southern Alpine domain.

Case study of the large-scale Mo-W mineralization in Eastern Qinling, China: Geology and genesis of the Yechangping porphyry-skarn system

Eastern Qinling Orogen is the largest Mo province in the world, hosting nine giant Mo deposits. Four giant Mo deposits contain economic W mineralization, while the mechanism of W mineralization remains unclear. The Yechangping deposit is a representative porphyry-skarn Mo-W deposit, with four paragenetic stages of prograde skarn, retrograde skarn, polymetallic sulfides and carbonate stage. Magmatism at Yechangping includes early barren monzogranite porphyry at 159.0 ± 1.5 Ma and late ore-related granite porphyry at ca. 145 Ma, and the latter porphyry shows a higher magmatic fractionation than the early barren monzogranite porphyry. Both barren and ore-related porphyries have similar high magma oxidation states, which may efficiently extract Mo during partial melting and hinder subsequent molybdenite crystallization until the porphyry-skarn Mo mineralization. Three types of scheelites are distinguished by their texture, paragenetic relationship and geochemistry, including Sch-1a in the retrograde skarn stage, and Sch-1b and Sch-2 in the polymetallic sulfides stage. Scheelite displays decreasing MoO3 contents from 7.01–51.59 % in Sch-1a, through 3.15–17.51 % in Sch-1b, to 0–1.51 % in Sch-2. The decreasing MoO3 contents in scheelite are attributed to the transformation of dominant Mo-bearing phases, i.e., from retrograde skarn stage powellite to polymetallic sulfides stage molybdenite. We suggest that the Mo-W mineralization is triggered by the decreasing oxygen fugacity, pH, and temperature, supported by thermodynamic modeling. In addition, the precipitation of fluorite and destabilization of fluorine complexes may have also promoted the Mo-W mineralization. Zircon Hf isotopes yielded εHf(t) values of −14.9 to −7.5 and TDM2 ages of 1671–2147 Ma, indicating that Yechangping porphyries were primarily sourced from the ancient basement of the Huaxiong Block, with additional contribution from the North Qinling Accretionary Belt. Skarn W mineralization in the southern part of Huaxiong Block may be controlled by both magmatic fertility and carbonate wall-rocks.

ПАМЯТИ СЕРГЕЯ ИВАНОВИЧА АНДРЕЕВА (30.05.1934–06.02.2023)

The article is dedicated to the memory of the Honoured Geologist of Russia, Doctor of Geological and Mineralogical Sciences Sergei Ivanovich Andreev, an outstanding researcher of the mineral resources of the World Ocean. Since 1976, Sergei Ivanovich Andreev headed a new direction at the Institute – the study of deep-sea minerals, being the head of the department of geology of solid ocean minerals, working until his last day. For many years, Sergei Ivanovich carried out a huge amount of research related to the problem of studying and developing the mineral resources of the World Ocean. He participated in the development of plans and methodological support for expeditionary work in the World Ocean, and was one of the main authors of the scientific and methodological basis for the study and development of deep-sea minerals in the World Ocean – ferromanganese nodules, cobalt-rich crusts and polymetallic sulphides. He was a pioneer of a new scientific direction – “Metallogeny of the World Ocean”. Sergei Ivanovich was the Scientific Director of the state project “Mineral Resources of the World Ocean”, participated in the study and discovery of large accumulations of PMN and CMC, which were subsequently taken into account when selecting the Russian Application Areas in the Pacific Ocean. Sergei Ivanovich was the Editor-in-chief and compiler of the unique “Metallogenic Map of the World Ocean” at a scale of 1:10,000,000 and a great number of other maps of ocean minerals. He was the author and co-author of over 300 published works, including 17 monographs and encyclopaedic publications, and 8 atlases. The article presents biographical data, and highlights the scientific achievements and personal qualities of S. I. Andreev.

Dynamic characteristics of two-vent submarine hydrothermal plumes: A case study of Longqi hydrothermal field

Submarine hydrothermal plumes play an important role in the process of material and energy exchange in the deep sea. Due to the influence of complex environmental factors (multiple vents, deep-sea stratified environment) and the limitation of observation capabilities, the dynamic characteristics of submarine hydrothermal plumes have not been fully understood, and it is urgent to study the diffusion and evolution process of submarine hydrothermal plumes by the computational fluid dynamics (CFD) model. In this paper, a CFD model was established to effectively simulate the diffusion and evolution process of two-vent submarine hydrothermal plumes under the deep-sea stratified environment, obtained the three-dimensional plume flow field structure of two-vent submarine hydrothermal plumes, and obtained the spatial distribution of dynamic characteristics parameters such as velocity, turbulent viscosity, turbulent kinetic energy and turbulence dissipation rate of two-vent submarine hydrothermal plumes. The equations for calculating the maximum plume rise height and the neutrally buoyant plume height of a two-vent submarine hydrothermal plume were deduced and established. In addition, a comparative analysis of the single-vent submarine hydrothermal plume revealed the mechanism of the influence of the key characteristics of the two-vent submarine hydrothermal plumes such as the maximum plume rise height. It was applied to analyze the dynamic characteristics of the plume occurred in Longqi hydrothermal field in the southwest Indian Ocean, and the results were verified by the field observation data. The spatial distribution of mass concentration of hydrothermal plume particles was further analyzed, and the difference of mass concentration in different hydrothermal plume structures was compared to study the exchange mechanism of material and energy between submarine hydrothermal plume and surrounding seawater. The results are of guiding significance for the tracing of submarine hydrothermal vents, the study of marine material exchange and energy transport processes, and the exploration and environmental evaluation of submarine polymetallic sulfide resources.

ГЕОЛОГОРАЗВЕДОЧНЫЕ РАБОТЫ НА ГЛУБОКОВОДНЫЕ ПОЛИМЕТАЛЛИЧЕСКИЕ СУЛЬФИДЫ В ОСЕВОЙ ЗОНЕ СРЕДИННО-АТЛАНТИЧЕСКОГО ХРЕБТА: РЕЗУЛЬТАТЫ ИССЛЕДОВАНИЙ В РОССИЙСКОМ РАЗВЕДОЧНОМ РАЙОНЕ

An overview of Russian studies of deep-sea polymetallic sulfides (PМS) in the axial zone of the Mid-Atlantic Ridge (MAR) at the Russian Exploration Area (REA‒PMS) is presented. A brief geological description of the axial zone of the MAR and PMS sites discovered and studied for almost forty years before and after the signing of an exploration contract with the International Seabed Authority in 2012 is given. Information on methods for conducting searches and exploration of PMS, technical equipment, as well as on metallurgical processing of raw materials is presented.

МИНЕРАЛЬНО-СЫРЬЕВЫЕ РЕСУРСЫ ТВЕРДЫХ ПОЛЕЗНЫХ ИСКОПАЕМЫХ МИРОВОГО ОКЕАНА: СОВРЕМЕННЫЕ РЕАЛИИ И ПОТЕНЦИАЛ РУДОНОСНОСТИ

Based on quantitative indicators of accumulations of the main types of solid minerals of the World Ocean: iron-manganese nodules, cobalt-rich manganese crusts and deep-sea polymetallic sulfides, an assessment of the ore potential was carried out both on the scale of the entire ocean and within the application areas of the Russian Federation. A price assessment of all types of ocean ores has been carried out, while it is shown that it is only a rank guideline indicating their exceptional importance for global mineral resource security.

Geophysical VLF prospecting for vein-type gold-bearing polymetallic sulphide deposits in the Sudetes (SW Poland)

Geophysical VLF prospecting for vein-type gold-bearing polymetallic sulphide deposits in the Sudetes (SW Poland)

Fluid evolution and genesis of the Zhuanghuhe Au–Sb mineralization in the Duobaoshan orefield, Northeast China: Evidence from fluid inclusions and H–O–C isotopes

The newly discovered Zhuanghuhe Au–Sb occurrence is located 20 km north of the famous Duobaoshan Cu–Mo deposit, it is the first gold–antimony deposit discovered in the Duobaoshan orefield. The hydrothermal quartz vein-type orebodies occur in the Middle Ordovician Duobaoshan Formation and are controlled by NNW and ENE compressional faults. Four mineralization stages are identified: stage I quartz + pyrite + arsenopyrite, stage II quartz + polymetallic sulfides, stage III quartz + stibnite, and stage IV quartz + calcite. Fluid inclusions (FIs) in quartz and calcite veins include six types: types I (two-phase aqueous), IIa (aqueous–carbonic; the volume of the carbon phase <50 %), IIb (aqueous–carbonic; the volume of the carbon phase >50 %, with more CO2 than CH4), IIc (aqueous–carbonic; the volume of the carbon phase >50 %, with more CH4 than CO2), IIIa (carbonic, with more CO2 than CH4) and IIIb (carbonic, with more CH4 than CO2). FIs of stage I are types I, IIa, IIb and IIIa, with homogenization temperatures of 279–311 °C and salinities of 4.87–11.84 wt%, indicating a medium-temperature low-salinity immiscible NaCl–H2O–CO2 fluid system. Stage II contains all FI types with final homogenization temperatures of 233–288 °C and salinities of 4.94–8.67 wt%, indicating a medium- to low-temperature low-salinity NaCl–H2O–CO2–CH4 system. FIs of stage III contain types I and IIa with homogenization temperatures of 193–240 °C and salinities of 3.85–6.63 wt%, belong to a low-temperature low-salinity NaCl–H2O–CO2 ± CH4 system. FIs of stage IV contain only type I with homogenization temperatures of 158–212 °C and salinities of 2.56–4.01 wt%, indicating a NaCl–H2O system. The H–O–C isotope data show that the NaCl–H2O–CO2 fluids of stage I (δD = −98 to −105.7 ‰, δOH2O = 5.7 to 6.9 ‰, δ13CCO2 = −11.9 to −11.1 ‰) were derived from a magmatic system, the fluids of stage II (δD = −85.7 ‰, δOH2O = 2.8 ‰, δ13CCO2 = −14.2 ‰, δ13CCH4 = −32.5 to −31.9 ‰) were characterized by the addition of CH4, which might have come from the reaction between the original ore-forming fluids and carbonaceous slate of the Duobaoshan Formation. The fluids in stage III (δD = −90.2 to −89.6 ‰, δOH2O = −9.1 to −6.1 ‰) and stage IV (δD = −110.6 to −96.3 ‰, δOH2O = −13.0 to −12.6 ‰) were characterized by mixing of meteoric water. According to the geology, fluid inclusion and H-O-C stable isotope evidences, the initial magma-derived NaCl-H2O-CO2 fluids were immiscible in stage I and then the process of mixing with CH4-bearing fluids in stage II, resulting in the gold precipitation; the precipitation of antimony was mainly related to the temperature drop and the mixing of meteoric water in stage III.

A giant porphyry-skarn-epithermal Mo-W-Cu-Zn-Pb-Ag metallogenic system in the Nannihu ore field, southern North China Craton: Constraints from new geochronological and pyrite geochemical data

The southern North China Craton owns substantial Mo, W, Zn, Pb, Cu, and Ag resources, and most of them are hosted in hydrothermal deposits that may co-exist in the same ore field. However, the relationship between the different types of deposits is not well-constrained. To better understand this, here we present a comprehensive geological, geochronological, and pyrite geochemical study on the Nannihu ore field in the Luanchuan district. The Nannihu ore field is largely represented by the Nannihu Mo-W deposit, Luotuoshan Zn-Cu-W deposit, and Lengshuibeigou Pb-Zn-Ag deposit. Mo-W mineralization at Nannihu occurs in the contact zone between the Nannihu intrusion and the wall rocks, showing typical characteristics of the porphyry-type deposit. Three paragenetic stages are recognized at Nannihu, including quartz-potassium feldspar stage, quartz-sulfide stage, and quartz-carbonate stage. The Zn-Cu-W orebodies at Luotuoshan are mainly layered or lens-like, occurring within the skarn zones in the Luanchuan Group. Skarn stage, polymetallic sulfide stage, and carbonate stage are revealed at Luotuoshan. Pb-Zn-Ag mineralization at Lengshuibeigou is characterized by banded sulfide veins that are hosted in the NNE-trending fault zone. Three paragenetic stages are developed at Lengshuibeigou: quartz-pyrite stage, quartz-polymetallic sulfide stage, and quartz-carbonate stage. New geochronological data confirm that the Nannihu intrusion was formed by at least two phases of magmatism including the granite porphyry (zircon U-Pb age of 145 ± 2 Ma) and the porphyritic monzogranite (zircon U-Pb ages of 142 ± 1 Ma and 140 ± 1 Ma), which accompanied by two episodes of Mo mineralization at the Nannihu deposit identified by molybdenite Re-Os dating (144.9 ± 0.7 Ma and 142.8 ± 0.6 Ma). The Luotuoshan deposit and Lengshuibeigou deposit formed at 141 ± 1 Ma to 140 ± 1 Ma and 140 ± 3 Ma to 139 ± 3 Ma revealed by U-Pb dating of garnet and monazite, respectively, which are contemporaneous with the late episode of the Nannihu intrusion and Mo mineralization. Pyrite grains of the three deposits have Co/Ni ratios higher than 1, suggesting a unified magmatic-hydrothermal origin for them. Pyrite from Nannihu and Luotuoshan is enriched in Co, Ni, Se, Mo, Mn, and Bi, whereas pyrite from Lengshuibeigou contains high Zn, Pb, As, Cu, Ag, and Au. The regular elemental distribution of pyrite in the Nannihu ore field is consistent with that of typical porphyry-related systems worldwide.Collectively, the Early Cretaceous magmatic rocks and diverse deposits in the Nannihu ore field make up a giant magmatic-hydrothermal Mo-W-Cu-Zn-Pb-Ag metallogenic system, with the porphyry, skarn, and epithermal types of mineralization displaying a zonation from inside to outside. The multi-episode magmatism and mineralization could result in the remarkable enrichment of mineral resources. The close spatial relationship among different types of mineralization in the Nannihu ore field has a significant implication for porphyry-related mineral prospecting in the southern NCC.

Revealing Heavy Metal-Resistant Mechanisms and Bioremediation Potential in a Novel Croceicoccus Species Using Microbial-Induced Carbonate Precipitation

Polymetallic nodules and polymetallic sulfides are currently the major mineral resources found on the seabed. The motivation behind deep-sea mining arises from the pursuit of valuable metals, driven by both economic and geopolitical considerations. However, before mining can be authorized, it is crucial to understand the microbial adaptation and biomineralization process related to heavy metals in deep-sea environments. To search for potential candidate materials for bioremediation in deep-sea environment, two strains with high resistance to manganese and the ability to form rhodochrosite precipitates were isolated from the deep-sea polymetallic nodule areas and hydrothermal polymetallic sulfide areas. Genomic analysis revealed that the strains employed various effective survival strategies, such as motility, chemotaxis, biofilm formation, metal redox, and transporters, to adapt to heavy metal environments. The bacterial strains Ery5 and Ery15 promote the formation of carbonate crystals by creating an excessively alkaline environment and releasing extracellular polymeric substances (EPSs). Furthermore, strains Ery5 and Ery15 were identified using polyphasic taxonomy methods and proposed as a new species belonging to the genus Croceicoccus. This study presents potential candidates for bioremediation in deep-sea environments.

Core-Shell Structure Trimetallic Sulfide@N-Doped Carbon Composites as Anodes for Enhanced Lithium-Ion Storage Performance.

The high specific capacity of transition metal sulfides (TMSs) opens up a promising new development direction for lithium-ion batteries with high energy storage. However, the poor conductivity and serious volume expansion during charge and discharge hinder their further development. In this work, trimetallic sulfide Zn-Co-Fe-S@nitrogen-doped carbon (Zn-Co-Fe-S@N-C) polyhedron composite with a core-shell structure is synthesized through a simple self-template method using ZnCoFe-ZIF as precursor, followed by a dopamine surface polymerization process and sulfidation during high-temperature calcination. The obvious space between the internal core and the external shell of the Zn-Co-Fe-S@N-C composites can effectively alleviate the volume expansion and shorten the diffusion path of Li ions during charge and discharge cycles. The nitrogen-doped carbon shell not only significantly improves the electrical conductivity of the material, but also strengthens the structural stability of the material. The synergistic effect between polymetallic sulfides improves the electrochemical reactivity. When used as an anode in lithium-ion batteries (LIBs), the prepared Zn-Co-Fe-S@N-C composite exhibits a high specific capacity retention (966.6 mA h g-1 after 100 cycles at current rate of 100 mA g-1) and good cyclic stability (499.17 mA h g-1 after 120 cycles at current rate of 2000 mA g-1).