Search Results (67)

With the rapid increase in global lithium demand, the exploration of newly discovered lithium in the bauxite of the Wenshan area in southeastern Yunnan has become increasingly important. However, the current research on clay-type lithium in the Wenshan area has primarily focused on local exploration, and large-scale predictive metallogenic studies remain limited. To address this, this study utilized multi-source remote sensing data from ZY1-02D and ASTER, combined with ALOS 12.5 m DEM and Sentinel-2 imagery, to carry out remote sensing mineral identification, structural interpretation, and prospectivity mapping for clay-type lithium in the Wenshan area. This study indicates that clay-type lithium in the Wenshan area is controlled by NW, EW, and NE linear structures and are mainly distributed in the region from north of the Wenshan–Malipo fault to south of the Guangnan–Funing fault. High-value areas of iron-rich silicates and iron–magnesium minerals revealed by ASTER data indicate lithium enrichment, while montmorillonite and cookeite identification by ZY1-02D have strong indicative significance for lithium. Field verification samples show the highest Li₂O content reaching 11,150 μg/g, with six samples meeting the comprehensive utilization criteria for lithium in bauxite (Li₂O ≥ 500 μg/g) and also showing an enrichment of rare earth elements (REEs) and gallium (Ga). By integrating stratigraphic, structural, mineral identification, geochemical characteristics, and field verification data, ten mineral exploration target areas were delineated. This study validates the effectiveness of remote sensing technology in the exploration of clay-type lithium and provides an applicable workflow for similar environments worldwide. Full article

This study explores the magmatic and hydrothermal evolution of porphyry–skarn–transitional Cu-Mo-W-Au systems within the Nilüfer Mineralization Complex (NMC), located in the westernmost segment of the Eocene Tavşanlı Metallogenic Belt, NW Türkiye. Through integration of field data, whole-rock geochemistry, Re–Os molybdenite dating, and amphibole–biotite mineral chemistry, the petrogenetic controls on mineralization across four spatially associated mineralized regions (Kirazgedik, Güneybudaklar, Kozbudaklar, and Delice) were examined. The earliest and thermally most distinct phase is represented by the Kirazgedik porphyry system, characterized by high temperature (~930 °C), oxidized quartz monzodioritic intrusions emplaced at ~2.7 kbar. Rising fO₂ and volatile enrichment during magma ascent facilitated structurally focused Cu-Mo mineralization. At Güneybudaklar, Re–Os geochronology yields an age of ~49.9 Ma, linking Mo- and W-rich mineralization to a transitional porphyry–skarn environment developed under moderately oxidized (ΔFMQ + 1.8 to +0.5) and hydrous (up to 7 wt.% H₂O) magmatic conditions. Kozbudaklar represents a more reduced, volatile-poor skarn system, leading to Mo-enriched scheelite mineralization typical of late-stage W-skarns. The Delice system, developed at the contact of felsic cupolas and carbonates, records the broadest range of redox and fluid compositions. Mixed oxidized–reduced fluid signatures and intense fluid–rock interaction reflect complex, multistage fluid evolution involving both magmatic and external inputs. Geochemical and mineralogical trends—from increasing silica and Rb to decreasing Sr and V—trace a systematic evolution from mantle-derived to felsic, volatile-rich magmas. Structurally, mineralization is controlled by oblique fault zones that localize magma emplacement and hydrothermal flow. These findings support a unified genetic model in which porphyry and skarn mineralization styles evolved continuously from multiphase magmatic systems during syn-to-post-subduction processes, offering implications for exploration models in the Western Tethyan domain. Full article

The Karamaili Granite Belt (KGB) in the southern margin of the Eastern Junggar is the most important tin metallogenic belt in the southwestern Central Asian Orogenic Belt. The plutons in the western part have a close genetic relationship with tin mineralization. The zircon U-Pb ages of the Kamusite, Laoyaquan, and Beilekuduke plutons are 315.1 ± 3.4 Ma, 313.6 ± 2.9 Ma, and 316.5 ± 4.6 Ma, respectively. The plutons have high silica (SiO₂ = 75.53%–77.85%), potassium (K₂O = 4.43%–5.42%), and alkalis (K₂O + Na₂O = 8.17%–8.90%) contents and low ferroan (Fe₂O₃^T = 0.90%–1.48%), calcium, and magnesium contents and are classified as metaluminous–peraluminous, high-potassium, calc-alkaline iron granite. The rocks are enriched in Rb, Th, U, K, Pb, and Sn and strongly depleted in Ba, Sr, P, Eu, and Ti. They have strongly negative Eu anomalies (δEu = 0.01–0.05), 10,000 Ga/Al = 2.87–4.91 (>2.6), showing the geochemical characteristics of A-type granite. The zircon U/Pb ratios indicate that the above granites should be I- or A-type granite, which is generally formed under high-temperature (768–843 °C), low-pressure, and reducing magma conditions. The high Rb/Sr ratio (a mean of 48 > 1.2) and low K/Rb ratio (53.93–169.94) indicate that the tin-bearing plutons have undergone high differentiation. The positive whole-rock εNd(t) values (3.99–5.54) and the relatively young Nd T_2DM model ages (616–455 Ma) suggest the magma is derived from partially melted juvenile crust, and the underplating of basic magma containing mantle materials that affected the source area. The results indicate the KGB was formed in the tectonic transition period in the late Carboniferous subduction post-collision environment. Orogenic compression influenced the tin-bearing plutons in the western part of the KGB, forming highly differentiated and reduced I, A-type transition granite. An extensional environment affected the plutons in the eastern sections, creating A-type granite with dark enclaves that suggest magma mixing with little evidence of tin mineralization. Full article

This study critically examines the early Cretaceous carbonate-hosted Zn-Pb (±Ba±Cu) deposits of the Malayer-Esfahan (MEMB) and Yazd-Anarak (YAMB) metallogenic belts in Iran, which have been inaccurately classified as Mississippi Valley type (MVT) deposits by Nejadhadad et al. (2025). Our findings reveal significant differences in mineralogy, fluid inclusion characteristics, and geochemical signatures compared to typical MVT deposits. These deposits are more akin to Irish-type Zn-Pb mineralization and formed in extensional and passive margin environments around the Nain–Baft back-arc basin. The normal faults in this back-arc rift can transform significantly during inversion and compressional tectonics, reactivating to behave as reverse faults and leading to new geological structures and landscapes. Our study highlights barite replacement as a crucial factor in forming sediment-hosted Zn-Pb (±Ba±Cu) and barite-sulfide deposits. Based on textural evidence, fluid inclusion data, and sulfur isotope analyses, we propose that barite plays a fundamental role in controlling subsequent Zn-Pb (±Ba±Cu) mineralization by serving as both a favorable host and a significant sulfur source. Furthermore, diagenetic barite may act as a precursor to diverse types of sediment-hosted Zn-Pb (±Ba±Cu) mineralization, refining genetic models for these deposits. Sulfur isotope analyses of Irish-type deposits show a broad δ³⁴S range (−28‰ to +5‰), indicative of bacterial sulfate reduction (BSR). Nevertheless, more positive δ³⁴S values (+1‰ to +36‰) and textural evidence in shale-hosted massive sulfide (SHMS) deposits suggest a greater role for thermochemical sulfate reduction (TSR) in sulfide mineralization. Full article

Haigou deposit, located in Dunhua City, southeast Jilin Province, NE China, is a large-scale gold deposit. The gold ore body is categorized into two types: quartz-vein type and altered rock type, with the quartz-vein type being predominant. The vein gold ore body primarily occurs within the monzonite granite and monzonite rock mass in the Haigou area and is controlled by fault structures trending northeast, northwest, and near north-south. In order to constrain the age and tectonic setting of quartz vein-type gold mineralization, we conducted a detailed underground investigation and collected samples of monzonite granite and pyroxene diorite porphyrite veins related to quartz-vein-type gold mineralization for LA-ICP-MS zircon U-Pb dating and whole-rock main trace element data testing to confirm that monzonite granite is closely related to gold mineralization. Pyroxene diorite porphyry and gold mineralization were found in parallel veins. The zircon U-Pb weighted mean ages of monzonite and pyroxene diorite porphyrite veins are 317.1 ± 3.5 Ma and 308.8 ± 3.0 Ma, respectively, indicating that gold mineralization in monzonite, pyroxene diorite porphyrite veins, and quartz veins occurred in the Late Carboniferous. The monzonite granite and pyroxene diorite porphyrite veins associated with quartz vein-type gold mineralization have high SiO₂, high K, and high Al₂O₃ and are all metaluminous high-potassium calc-alkaline rock series. Both of them are relatively enriched in light rare earth elements (LREE) and macroionic lithophile elements (LILE: Rb, Ba, K, etc.), but deficient in heavy rare earth elements (HREE) and high field strength elements (HFSE: Nb, Ta, P, Ti, etc.), the monzonitic granite Eu is a weak positive anomaly (δEu = 1.15–1.46), the pyroxene diorite porphyre dyke Eu is a weak positive anomaly (δEu = 1.09–1.13), and the Nb and Ta are negative anomalies. The Th/Nb values are 0.28–0.73 and 1.48–2.05, and La/Nb are 2.61–4.74 and 4.59–5.43, respectively, suggesting that diagenetic mineralization is the product of subduction in an active continental margin environment. In recent years, scholarly research on Sr, Nd, and Pb isotopes in Haigou rock masses has indicated that the magmatic source region in the Haigou mining areas is complex. It is neither a singular crustal source nor a mantle source but rather a mixed crust-mantle source, primarily resulting from the partial melting of lower crustal materials, with additional contributions from mantle-derived materials. In summary, the metallogenic characteristics, chronology data, geochemical characteristics, and regional tectonic interpretation indicate that at least one phase of magmatic-hydrothermal gold mineralization was established in the Late Carboniferous as a result of the subduction of the Paleo-Asian ocean plate at the northern margin of the North China Craton. Full article

Geotechnical slope failures—often precursors to catastrophic landslides and collapses—pose significant risks to mining operations and regional socioeconomic stability. Focusing on the Jiangte Xikeng lithium open-pit mine, this study integrates field reconnaissance, laboratory testing, and multi-physics numerical modeling to elucidate the mechanisms governing slope stability. Geological surveys and core analyses reveal a predominantly granite lithostratigraphy, bisected by two principal fault systems: the NE-striking F01 and the NNE-oriented F02. Advanced three-dimensional finite element simulations—accounting for gravitational loading, hydrogeological processes, dynamic blasting stresses, and extreme rainfall events—demonstrate that strain localizes at slope crests, with maximum displacements reaching 195.7 mm under blasting conditions. They indicate that differentiated slope angles of 42° for intact granite versus 27° for fractured zones are required for optimal stability, and that the integration of fault-controlled instability criteria, a coupled hydro-mechanical-blasting interaction model, and zonal design protocols for heterogeneous rock masses provides both operational guidelines for hazard mitigation and theoretical insights into excavation-induced slope deformations in complex metallogenic environments. Full article

This study analyzes the ore potential of the tectono-stratigraphic zones in the Shyngys-Tarbagatai folded system using metallogenic diagrams. These diagrams condense extensive geological and metallogenic data, illustrating stratified and intrusive formations, formation types, depositional environments, and ore loads in chronological sequence. The analysis highlights variations in ore mineralization intensity across the zones, identifying both highly and less ore-bearing areas. Most zones show polymetallic mineralization with 2 to 12 types of minerals; gold and copper are present in all zones. Temporal analysis identified key productive levels in the Late Ordovician, Early Silurian, and Early Devonian, corresponding to active stages of island arcs, forearc and backarc basins, and the Devonian volcanic–plutonic belt. The structures of the Shyngys-Tarbagatai folded system are classified as island-arc structures of active continental margins. Comparing the ore potential of its tectono-stratigraphic zones with similar modern structures shows that, except for the Maikain zone, all others have significantly lower ore potential. The obtained data is most likely a result of the region’s poor exploration coverage. As such, future efforts should prioritize further investigation of the identified mineralization zones. This is evident from the dominance of small, medium, and large deposits, and ore occurrences in all tectono-stratigraphic zones when assessing their ore potential. Preliminary analysis of the ore potential in the tectono-stratigraphic zones of the Shyngys-Tarbagatai folded system, based on metallogenic diagrams, clearly supports the need for regional and exploration studies. These should focus on poorly explored stratigraphic levels, ore-bearing geological formations, and geodynamic settings that are favorable for deposit formation. This will provide a more accurate assessment of the potential in these zones. Full article

Metallic minerals and some nonmetallic deposits (such as gas hydrate and natural gas) exhibit significant resistivity contrast with their surrounding rocks. Therefore, magnetotelluric (MT) sounding, which is highly sensitive to low-resistivity anomalies, offers a unique advantage in identifying these mineral resources. For metallogenic systems in sedimentary environments with approximately layered structures, we propose the Dynamic Error Bat Algorithm (DEBA), which integrates the cooling strategy, the dynamized fit error function, and the Bat Algorithm. DEBA enhances the breadth of global exploration in the early iteration stages while focusing on the depth of local exploitation in the later stages, yielding a more effective fitting outcome and better identification of electrical interfaces. Validity and noise immunity tests on typical synthetic models prove the robustness of DEBA. For broadband MT stations from the central Songliao Basin, we observed that the model derived from three-dimensional inversion did not provide an ideal layering effect for the shallow structure. Notably, the apparent resistivity and phase curves of these MT stations are similar, suggesting that the shallow structure in the study area has approximately one-dimensional (1-D) features, a conclusion that was further supported by phase tensor analysis. To gain a clearer understanding of the shallow structure, we applied DEBA to perform an averaged 1-D inversion. The subsequent results reveal a low-resistivity layer, which may be attributed to metallic sulfides or saline fluids. Full article

The Carboniferous Benxi Formation in southern Shanxi of North China has significant bauxite resource potential; however, the source of its metallogenic material and its sedimentary environment remain unclear. The microscopy, X-ray diffraction, X-ray fluorescence spectroscopy, and inductively coupled plasma mass spectrometry methods were applied in this study to examine the mineralogical, petrographic, and geochemical characteristics. Geochemical proxies of La/Y, Sr/Ba, Al₂O₃/TiO₂, Zr/Sc, Th/Sc, La/Sc, and Th/Co were analyzed to investigate the paleo-depositional environment and provenance of the aluminum-bearing strata. The findings indicate that diaspores are the primary ore minerals in bauxite, while kaolinite and rutile are the predominant gangue minerals. Both the bauxite and claystone/aluminous rocks exhibit high enrichment in Li, Bi, and U, with relative enrichment in In, Sb, Th, Nb, and Ta. Li is notably concentrated in the claystone/aluminous rocks, reaching up to 1994.00 μg/g, primarily occurring in cookeite and boehmite, while U is highly concentrated in the bauxite. The aluminum-bearing strata were primarily formed under alkaline-reducing conditions, with changes in acidity and alkalinity of the environment during the sedimentary diagenetic process. Marine transgressions significantly impacted the sedimentary environment of the aluminum-bearing strata, and the paleoclimate was characterized as hot and humid. The principal factors contributing to enrichment of aluminum in the sedimentary basin were the in situ weathering of aluminum-rich source rocks and the transport of clastic materials from high-aluminum source rocks. The source rocks were closely associated with intermediate-acidic magmatic rocks and potentially related to the weathering of Ordovician carbonates. Full article

In the Huanggangliang–Ganzhuermiao metallogenic belt in the southern Great Xing’an Range, the Haobugao Pb–Zn deposit is the most widespread skarn-type polymetallic deposit. The observed mineralization processes in this area are closely associated with both magmatic and tectonic activity. The zircon U–Pb ages of two granitoid phases are 134.0 ± 0.6 Ma and 133.4 ± 0.9 Ma (Early Cretaceous). High SiO₂ content (average mass fractions of 77.98 wt.% and 73.25 wt.%), high alkalinity (average mass fractions of 6.19 wt.% and 8.78 wt.%), and low CaO levels (average mass fractions of 0.16 wt.% and 0.12 wt.%) are characteristic of these rocks. They are also enriched in high-field-strength elements (HFSEs) (Th, U, Ta, Zr, Hf, etc.) and depleted in large ion lithophile elements (LILEs) (Ba, Sr, etc.). Furthermore, the Nb/Ta ratios (7.80~8.82, 10.00~10.83) point to a crustal origin of the magma. The zircon Hf isotopic compositions suggest that the melting of young crust derived from Meso-Neoproterozoic and Neoproterozoic depleted mantle gave rise to the magma in these granite porphyries. These rocks formed in an extensional environment driven by the subduction and retreat of the Paleo-Pacific plate during the Early Cretaceous. Full article

The Xinjiazui gold deposit marks a notable significance in prospecting within the Back-Longmenshan tectonic belt, located on the northwest margin of the Yangtze Block, China. Despite the extensive studies conducted on this deposit, the source of the ore-forming materials remains unclear, leading to ongoing debates regarding the genesis of this deposit. This study analyzed in situ (EPMA and LA-ICP-MS) trace elements and S-Pb isotopes of arsenopyrite, solely from the principal metallogenic stage and paragenetic with native gold. The results show that the gold in arsenopyrite occurs as invisible gold (Au³⁺), with an average concentration of 9.38 ppm, whereas the concentrations of magma-related elements, such as W, Sn, Mo, and Bi, are very low. The sulfur isotopes (³⁴S) of arsenopyrite range from 8.32‰ to 10.16‰, aligning closely with the deep metamorphic basement (Pt₃l). Meanwhile, the lead isotopes in arsenopyrite display characteristics typical of those found in orogenic belts. A comprehensive analysis of the abundance of gold indicated that the metallogenic materials (sulfur and gold) primarily originated from Pt₃l. Additionally, the arsenopyrite thermobarometer indicated that the Xinjiazui gold deposit formed in a medium–low-temperature, medium metallogenic environment (5.57–8.69 km), with a sulfur fugacity (log f (S₂)) below −8.4. Combined with previous research results, this study proposes that the Xinjiazui gold deposit is a subduction-related mesozonal orogenic gold deposit. In gold prospecting and exploration in the Back-Longmenshan tectonic belt, it is essential to focus on the distribution of brittle-ductile shear zones and location of the quartz veins associated with pyrite and arsenopyrite mineralization. Full article

The Dashigou deposit is one of the most representative carbonatite-type Mo-REE deposits in the East Qinling metallogenic belt of China, with a molybdenum resource of more than 180 kt and a rare earth resource of 37.8 kt. Recent exploration has revealed a considerable scale of uranium mineralization within this deposit. Therefore, this study conducted detailed mineralogical and EPMA U-Th-Pb chemical dating on the uranium mineralization in the Dashigou deposit. The results indicate that the U-ore body in the Dashigou deposit mainly consists in carbonatite veins, and principally as anhedral, mesh-like uraninite. The mineral assemblage is characterized by uraninite + rutile + bastnasite + parisite or brannerite. The uraninite displays geochemical compositions of high Y and Ce and low Si, Ti, and Mg. The EPMA U-Th-Pb chemical dating is 144 ± 3.1 Ma, representing the Yanshanian uranium mineralization age in the region. The newly discovered uranium mineralization age indicates that the deposit experienced a uranium remobilization event during the Cretaceous and was formed in an intracontinental orogenic and extensional environment post-collision orogeny. Full article

The Xifanping deposit is a distinct Cenozoic porphyry Cu (Au) deposit located in the Sanjing porphyry metallogenic belt 100–150 km east of the JinshajFiang fault in the western Yangtze craton. We present new zircon U–Pb–Lu–Hf isotopic studies and geochemical data of the ore-bearing quartz monzonite porphyry from the Xifanping deposit to determine their petrogenesis and geodynamic mechanisms. LA–ICP–MS zircon U–Pb dating yielded precise emplacement ages of 31.87 ± 0.41 Ma (MSWD = 0.86) and 32.24 ± 0.61 Ma (MSWD = 1.8) for quartz monzonite porphyry intrusions, and 254.9 ± 5.1 Ma (MSWD = 1.7) for inherited zircons of the monzonite porphyry. The ore-bearing monzonite porphyry is characterized by high-K calc–alkaline to shoshonite and peraluminous series, relatively enriched in light over heavy REEs, with no distinct Eu anomalies, as well as enrichment in LILEs and depletion of HFSEs, with adakitic affinities. The zircon Lu–Hf isotope data ranged from εHf(t) values of −2.94 to +3.68 (average −0.47) with crustal model (T_DM2) ages ranging from 0.88 to 1.30 Ga, whereas the inherited zircons displayed positive εHf(t) values ranging from +1.83 to +7.98 (average +5.82), with crustal model (T_DM2) ages ranging from 0.77 to 1.17 Ga. Results suggest that the Xifanping porphyry Cu (Au) deposit is related to two periods of magmatic activities. Early magmas were generated from the Paleo-Tethys oceanic subduction during the Late Permian. The subsequent porphyry magma was likely formed by the remelting of previously subduction-modified arc lithosphere, triggered by the continental collision between the Indian and Asian plates in the Cenozoic. The deep magmas and late hydrothermal fluids took advantage of the early magma transport channels along tectonically weak zones during the transition from an extrusive to an extensional–tensional tectonic environment. Early dikes from remelted and assimilated crust contributed to the two age ranges observed in the porphyry intrusions from the Xifanping deposit. The juvenile lower crust materials of the early magmatic arc were potential sources of the Cenozoic porphyry magmas, which has significant implications for mineral exploration and the geological understanding of porphyry Cu deposits in this region. Full article

The Washan iron deposits in Ningwu district contain different magma-related genetic natures, including magmatic, magmatic–hydrothermal and hydrothermal types, and their ore-forming processes remain a subject of debate. To elucidate the ore-forming processes of iron ores from Washan, we present textural, major element analytical, and thermal data of magnetites from various ore bodies in Washan, probing the crystallization conditions and subsequent formation sequence of magnetites. SEM analysis with back-scattered electron (BSE) imaging reveals diverse magnetite textures, including mineral inclusions, exsolution lamellae, and recrystallization features, reflecting the transitional environment from magmatic to hydrothermal. Based on Ti, V, and Cr compositions of magnetite from different ore bodies, two distinct evolution trends of genetic processes are identified, including evolution paths from porphyry-type to IOA- and IOCG-type magnetite. High-resolution WDS mapping highlights the intensifying alterations during this process. Calculated magnetite crystallization temperatures among different types of magnetite range from 597 °C to 378 °C, suggesting a cooling trend from porphyry-type magnetite (~558 °C) to IOA-type magnetite (~515–439 °C) and IOCG-type magnetite (~378 °C). These results underscore the significant role of magma-derived hydrosaline liquids and vapors in the formation of iron ores from Washan, where variations in the salinity of ore-forming fluids lead to different evolutionary paths for subsequent generations of magnetite. The metallogenic model of the Washan iron deposit suggests that highly saline, iron-rich fluids connect the varying geneses of magnetite, transitioning from deeply formed porphyry-type magnetite to IOA- or IOCG-type magnetite generated in the subaerial zone. Full article

The Carboniferous-Permian coal measure strata in the Qinshui Basin exhibit highly lithium (Li) enrichment, with substantial exploitation potential. To further explore the enrichment mechanism of lithium in coal measure strata, the No. 15 coal of the Taiyuan Formation from the Gaoping mine is taken as the research object, and its mineralogical and geochemistry characteristics are evaluated using optical microscopy, X-ray diffraction, scanning electron microscopy, inductively coupled plasma mass spectrometry, X-ray fluorescence, and infrared spectral. The results show that the No. 15 coal is semi-anthracite coal with low moisture, low ash, low volatility, and high sulfur. Organic macerals are primarily vitrinite, followed by inertinite, and liptinite is rare; the inorganic macerals (ash) are dominated by clay minerals (predominantly kaolinite, cookeite, illite, and NH₄-illite), calcite, pyrite, quartz, siderite, gypsum, and zircon. The average Li content in the coal is 66.59 μg/g, with higher content in the coal parting (566.00 μg/g) and floor (396.00 μg/g). Lithium in coal occurs primarily in kaolinite, illite, cookeite, and is closely related to titanium-bearing minerals. In addition, Li in organic maceral may occur in liptinite. The No. 15 coal was formed in the coastal depositional system, and the deposition palaeoenvironment is primarily a wet–shallow water covered environment in open swamp facies; the plant tissue preservation index is poor, and aquatic or herbaceous plants dominate the plant type. The reducing environment with more terrestrial detritus, an arid climate, and strong hydrodynamic effects is favorable for Li enrichment in coal. The results have important theoretical significance for exploring the enrichment and metallogenic mechanisms of Li in coal. Full article