Especially in the context of renewable energy, vanadium (V) is an important component of energy storage technology. Gabbroic rocks in crustal environments may host a considerable amount of V-bearing minerals such as magnetite, and ilmenite. This study focuses on primary V occurrences in Precambrian-Cambrian aged meta-gabbroic rocks of the Alaşehir-Manisa area in the central part of the Menderes Massif (Türkiye). The primary purpose of the study is twofold; 1) to determine the V potentiality of meta-gabbro and 2) to reveal the enrichment mechanism by determining the mineralogical and geochemical properties of gabbroic formations. The meta-gabbroic rocks in the study area can be divided into three subgroups based on the size distribution (fine, medium, and coarse) of the minerals. The ore-bearing minerals observed in the meta-gabbroic rocks are construed by magnetite, ilmenite, titanomagnetite, rutile, pyrite, and hematite. The high-grade metamorphism of Menderes Massif progressively affected the gabbroic rocks resulting in the partial and complete transition of ilmenite minerals to rutile. However, the effect of metamorphism gradually decreases from outward to inward zones of the intrusion allowing an intact vanadiferous ilmenite-rich core in the entire gabbro body. 

The V enrichments are both hosted by oxide and sulphide-bearing phases. While the oxide phases are constituted by ilmenite and Ti-magnetite exsolutions, the sulphide minerals are pyrite and minor chalcopyrite. The V content of the studied meta-gabbro range from 281 to 628 ppm, with an average of 514 ppm. Contents of SiO₂, Al₂O₃, Fe₂O₃, MgO, TiO₂, and P₂O₅ are between 68.8-38.9%, 7.93-15.4%, 6.87-17.8%, 3.21-8.86%, 1.24-5.64%, 0.19-1.13%, respectively. V shows moderate to strong correlation with Ti, Zn, and Ga (R²= 0.51, 0.86, and 0.87, respectively) and there is a lack of correlation with Fe, Ni, and Cu indicating V³⁺ ion substituted Fe³⁺ in magnetite and Ti³⁺ in ilmenite. The other meta-gabbro intrusions of Menderes Massif generally lacked Ti-V enrichments, therefore Alaşehir meta-gabbro intrusion may gain economic importance in case of a tighter supply trend of these critical elements.

Keywords: Vanadiferous gabbro; Magnetite; Ilmenite; Menderes Massif; Alaşehir-Manisa (Türkiye)

How to cite: Sutcu, N. M., Doner, Z., Unluer, A. T., and Kumral, M.: Vanadium Enrichments of Meta-Gabbroic Rocks in central part of the Menderes Massif (Türkiye): The Incremental Effect of Magmatism and Metamorphism in Highly Siderophile Environments, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-716, https://doi.org/10.5194/egusphere-egu24-716, 2024.

• Uranium is generally mobilized in solutions in U⁶⁺-complexes and gets precipitated as compounds containing the U⁴⁺ ion. Here we report hydrothermal remobilization of U, and the simultaneous precipitation of U⁶⁺ and U⁴⁺ in the Paleoproterozoic quartz-pebble conglomerate (QPC) from the Mankarchua basin, Singhbhum Craton, India. Uranium occurs associated with vein pyrite in the basal QPC of the Mankarchua basin, suggesting a clear hydrothermal origin of the mineralization. The pyrites occur linearly in veins and are replaced U-bearing minerals. Detrital monazites are the source of U. Newly formed fine-grained U-free monazites are observed along with crandallite series minerals (Ca,Ba,Sr,Pb)Al₃(PO_3.5(OH)_0.5)(OH)₆., suggesting alteration of detrital monazite by moderately oxidising acidic fluids. The remobilized U precipitates when it encounters pyrite and apatite. Brannerite (UTi₂O₆, containing U⁴⁺) forms concomitantly with the oxidation of pyrite, while autunite (Ca(UO₂)₂(PO₄)₂·10–12H₂O, containing U⁶⁺) forms by replacement of apatite. Thus, detrital or hydrothermal apatite enriched zones with or without pyrite may serve as U-traps for potential mineralization.

How to cite: Mallick, S. P., Mondal, A., and Lochan Pruseth, K.: Simultaneous precipitation of U4+ and U6+ in quartz-pebble conglomerate in the Singhbhum Craton, India., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-127, https://doi.org/10.5194/egusphere-egu24-127, 2024.

The Sangan mining district consists of 14 iron ore deposits at the contact of Eocene granitoids to Mesozoic sedimentary rocks. Syenite, syenogranite and granite represent the fertile Sarnowsar intrusion and monzogranite to syenogranite barren Sarkhar and Bermani intrusions. LA-ICP-MS U-Pb zircon ages of fertile syenogranite samples are between 39.6 ± 0.7 and 39.1 ± 0.4 Ma corresponding to lithospheric thinning by Eocene flare-up magmatism. Barren Sarkhar and Bermani intrusions (monzogranites at 41.7 ± 0.6 and 41.9 ± 0.3 Ma; syenogranites between 37.4 ± 1.8 and 37.9 ± 1.7 Ma were emplaced contemporaneous with flare-up magmatism.

Plots of Nb vs. Ta, Y vs. Yb/Sm and Y vs. Ce/Ce* classify studied zircons as granitoid-type as parental magma. Uniformly high Hf contents of zircons indicate crystallization from a more evolved felsic magma, especially the Sarkhar and Bermani intrusions. In the U/Yb versus Hf and U versus Yb discrimination diagrams, all data plot in the continental-series and are clearly distinguishable from ocean crust zircons. In the U/Yb versus Nb/Yb diagram, both the whole-rock and zircon compositions show the characteristics of a magmatic-arc array. The Nb content of arc magmas is depleted relative to within-plate settings. As such, arc zircons possess lower Nb/Hf and higher Th/Nb ratios with a similar degree of magmatic fractionation. Bivariate discrimination diagrams such as Th/U versus Nb/Hf and Th/Nb versus Hf/Th indicate that most zircons plot in the orogenic field, signifying a magmatic arc or orogenic setting and a calc-alkaline parent magma. Fertile intrusions are characterized by a higher zircon Eu (>0.3) and Ce (>100) anomalies, 10,000*(Eu/Eu*)/Y (>1), (Ce/Nd)/Y (>0.001), and slightly lower Dy/Yb ratios (0.21 to 0.38) than zircons in barren intrusions with Dy/Yb ratios (0.2 to 0.51) and lower Eu and Ce anomalies. The chondrite normalized zircon Eu/Eu* ratio correlates with whole rock La/Yb and has been used to estimate the crustal thickness. Our results reveal that fertile Sarnowsar granitoids formed in thicker crust (48 to 66 km) than barren Sarkhar and Bermani (25 to 38 km) granitoids. As the granitoids formed in adjacent areas, these differences in crustal thickness imply either a heterogeneously composed crust, or the iuxaposition of units across a major fault, or hitherto unknown complications with the method. The zircon/rock partition coefficients of REEs, and Y, Nb, Ta, Th, and U contents indicate that the trace element patterns of the studied granitoids are controlled by the liquid composition at the magmatic crystallization. Compared to Sarkhar and Bermani magmatism, Sarnowsar magmatism has a higher temperature (736 to 915 °C), higher zircon/rock partition coefficient of REEs, Y and Th (up to 2770 for Zr), and it was formed in higher oxidant conditions (△FMQ values between -0.06 to 17.01). This indicates that the fertile intrusions are interpreted to indicate extremely high magmatic water content and oxidized like fertile porphyry systems. We suggest that oxidized and I-type magmas are more favorable to porphyry-skarn mineralization under arc tectonic settings. Such a conclusion could be used in regional exploration for porphyry-skarn mineralizations in the Cenozoic arc-related magmatism of Iran and elsewhere.

How to cite: Ghasemi Siani, M. and Neubauer, F.: Discrimination of fertile and barren skarn-related magmatism from Sangan Fe Skarn, NE Iran: Constrains from whole-rock geochemistry, zircon chemistry and crustal thickness, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-661, https://doi.org/10.5194/egusphere-egu24-661, 2024.

Critical raw materials (e.g., Co, Ni, Pt, Sc…) are very important resources for high technology applications (e.g., renewable energies, modern electronic devices, e-mobility, medical). Most of these minor and trace elements are produced as by-products of base metal mining. Magmatic Ni-Cu sulphide ore deposits are of great economic relevance worldwide. The BMBF-funded project “StratOre” (FKZ 033R278) aims to study the high-tech element potential of newly found sulphide deposits in ophiolite sequences in Indonesia, a country, which is well known for its large number of mineral deposits. Here we present the first results of our study addressing the nature of the Sebuku Island Fe-Ni-Co-Cu sulphide ore and the distribution of base and precious metals in different minerals.

Sebuku Island (SE-Kalimantan) is part of the Cretaceous accretionary Meratus collision complex and represents an obducted ophiolite at the convergent boundary of Sundaland in the NW and the compressing Paternoster microcontinent in the SE. This ophiolite complex consists of mafic-ultramafic layers and rocks of the upper mantle of Permian to Jurassic age. Cretaceous intrusions, meta-sediments and mafic-intermediate intrusions are overlain by Tertiary and Quaternary sediments. Serpentinization started prior to obduction and became affected by cretaceous magmatism and alteration. One of the Early Cretaceous intrusions is supposed to represent a mantle wedge and is marked by high-temperature serpentine (Sulistyohariyanto and Soesilo, 2017, Cahyadi et al., 2017, Imani et al., 2020).

Massive Fe-Ni laterite (mined since 2000 by PT SILO) is overlying a recently observed Fe-Ni-Co-Cu sulphide mineralization, which is hosted by high-temperature serpentinite in the cumulus zone of the ultramafic ophiolite complex. Our sample material is taken from 14 drill cores within depths of 22 m to 109 m. The studied mineralization occurs as massive, erratic and disseminated sulphides. Formation of the ore body is probably resulted from subsequent magmatic and hydrothermal processes. The base metal sulphide-ore mineralogy is represented mainly by pentlandite, pyrrhotite, pyrite, chalcopyrite and cobaltite; a large number of further sulphides and arsenides are observed as well. We highlight the extraordinary enrichment of Co in Fe-S, Fe-Ni-S and Ni-S minerals, as well as the extraordinary enrichment of Ni in pyrrhotite and pyrite. Platinum-group elements are not enriched in any of the ore types.

How to cite: Fuchs, A., Jacques, G., Graupner, T., Swamidharma, Y., Cahyadi, A., Krisnanto, Y., Ernowo, E., Idrus, A., and Vanessa, A.: Mineralogical characteristics of a Fe-Ni-Co-Cu sulphide mineralization in Sebuku Island, Indonesia., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1579, https://doi.org/10.5194/egusphere-egu24-1579, 2024.

The albite-lepidolite-topaz granite of Beauvoir is the last intrusion in a peraluminous granitic complex of Variscan age composed of three successively emplaced units: the hidden granite of La Bosse, the two-micas granite of Colettes, and the Beauvoir granite consisting of 3 units B1 to B3. Compared to similar Li-F-rich igneous bodies, the Beauvoir granite is highly enriched in Sn (200-1400 ppm), Ta (20-400 ppm) and Be (20-300 ppm). The B1 unit is composed of abundant albite and lepidolite laths forming a framework filled with globular quartz, K-feldspar, and rare crystals of topaz, Li-phosphates and Sn-Nb-Ta oxides. This work presents a quantitative mineralogical study of the Beauvoir granite (B1 unit) and detailed textural and chemical characterization of the Li-bearing micas from the cores from the PER and EMILI drilling campaigns. The first approcah of this work consisted in estimating the proportion of minerals, and thus determine their abundance by comparing estimates from in situ thin section mapping from micro-XRF and the calculation of mineral phase proportion from whole rock geochemistry on drill cores. The main trend is a "mix", for the fresh rocks, between an albite pole (> 35 %), and a quartz (~25 %) - lepidolite (~15-25 %) pole. The micas are represented, in the fresh facies, by trioctahedral lepidolite while the altered facies shows i) dioctahedral muscovite replacing the feldspars and lepidolite, and ii) lepidolite replaced partially or totallly by muscovite. Trace element composition of the lepidolite show high Li content with average 28000 ppm for lepidolite from the fresh facies and 24000 ppm for those from the altered facies. Compared to lepidolite, muscovite is not a Li-bearing but Sn-rich mineral. Our study shows that hydrothermal greisen alteration has almost no impact on the lithium content of the lepidolite but decrease the population of the lepidolite. The results obtained, combining to drilling data, will lead to a mineralogical model block of the Beauvoir quarry and better understand the magmatic-hydrothermal evolution of the deposit.

How to cite: Kahou, S., Cathelineau, M., and Boiron, M.-C.: Quantitative mineralogy and lithium distribution in the upper part of the Beauvoir granite, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1668, https://doi.org/10.5194/egusphere-egu24-1668, 2024.

The granites associated with large-scale W and Sn deposits generally have high concentrations of U, Th, and K, including but not limited to the Cornubian Batholith in Southwest England, the Krušné hory/Erzgebirge Batholith in Central Europe, the Sardinian Batholith in Italy, and the Gejiu Batholith and the Qianlishan granitic complex in South China. These granites can be classified as high heat producing (HHP) granites (>5 μW m^-3) because of high radiogenic heat production. However, how long radiogenic heat can prolong the suprasolidus lifetime of magmas and whether radiogenic heat exerts an influence on later W and Sn mineralization is poorly understood.

To answer these questions, finite element numerical modeling was established to link magma cooling by heat conduction with diffusion of W, Sn, and H₂O from silicate melts to coexisting aqueous fluids before the solidus is reached. The magma size (vertical thickness of 4–5 km and horizontal length of 20 km) is constrained by the granites associated with large-scale W and Sn deposits. The modeling results suggest that the suprasolidus lifetimes of HHP magmas are positively correlated with the heat production and magma thickness and negatively correlated with the solidus temperatures and the thermal conductivity of host rocks. Average radiogenic heat of 5–10 μW m^-3, together with decreased solidus temperatures due to magmatic differentiation and a moderate thermal conductivity of host rocks, can prolong the suprasolidus lifetime of HHP magmas by 49–427 ka (1 Ma = 1000 ka), corresponding to 11–85 % of the suprasolidus lifetime of equally sized magmas with normal radiogenic heat (2 μW m^-3). From the available gravity modeling data, over half of the granites associated with large-scale W and Sn deposits are at least 1 km thicker than the values calculated from the empirical power–law equation, and the modeling results indicate that an increase of 500–1000 m in magma thickness prolongs the suprasolidus lifetimes of HHP magmas (5 μW m^-3) by 50–74 %. During magma cooling before solidus is reached, the diffusion of W and Sn is at least several orders of magnitude slower than that of H₂O in hydrous melts; thus, the equilibrium partitioning of these two metals between silicate melts and coexisting aqueous fluids is not reached, and the metal diffusion from melts is a rate-limiting step. The prolongation of the suprasolidus lifetimes by radiogenic heat and decreased solidus temperatures can allow extraction of 17–95 % more W and Sn from silicate melts before the solidus is reached and increase the possibility of producing W and Sn mineralization at later stages. Therefore, the coexistence of HHP granites and large-scale W and Sn deposits is not accidental.

How to cite: Liu, X.-C. and Zhang, D.-H.: The links between high heat producing granites and large-scale W-Sn deposits: insight from numerical modeling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2829, https://doi.org/10.5194/egusphere-egu24-2829, 2024.

The Abovyan deposit in Armenia represents a unique example of relatively young, Late Miocene age Kiruna-type apatite-magnetite mineralization in the region. Initially identified in 1947 by a team of Armenian geologists, based on the well-pronounced magnetic anomaly, it remains largely obscure outside the confines of Soviet-era scholarly literature. This deposit resides within a magmatic formation predominantly of intermediate composition, comprising andesites and dacites, and characterized by disseminated and massive magnetite ores and transitional varieties between them. The deposit is fully covered by several dozens of meters of younger, Pliocene-Quaternary volcanic rocks, so the samples for our study were collected from drill cores. These specimens, encompassing both host rocks and ores, retain critical insights into the processes governing ore segregation and accumulation, despite having a large influence of the autometasomatic alteration. The young age (~6-7 Ma, K-Ar, Sarukhanyan, 1969) and, consequently, the absence of later metamorphic events in the area is the main advantage of the Abovyan deposit over the majority of Kiruna-type deposits around the world in terms of preservation of the initial textures and other mineralogical and petrological features. Several generations of the magnetite-apatite ores could be clearly distinguished in the ores, which include (1) magnetite melt-like droplets in the host-rocks, (2) massive magnetite apatite ores, (3) magnetite-hosted breccias of the altered host-rocks and (4) several generations of late hydrothermal veins. Notably, the apatite within these ores exhibits a remarkable enrichment in light rare earth elements (REEs), reaching concentrations as high as 4 wt.%. This level of enrichment is notably higher than that observed in other Kiruna-type deposits (Frietsch, Perdahl, 1995) and is accompanied by the other critical metals’ mineralization (e.g., Th). Ongoing research on the geochemistry and geochronology of the Abovyan deposit may be a key to understanding the formation of the Kiruna-type deposits and their REE potential, in particular.

This study was funded by the Science Committee of RA (Research projects №23PostDoc-1E001 and  № 22IRF‐08), and by the Swiss National Science Foundation (grant 200021_188714).

Frietsch, R., Perdahl, J. A., 1995. Rare earth elements in apatite and magnetite in Kiruna-type iron ores and some other iron ore types. Ore Geology Reviews, 9, 6, 489-510.

Sarukhanyan, L.B., 1969. Some questions about the genesis of the Abovyan apatite-magnetite deposit. Proceedings of the Armenian SSR Academy of Science, Earth Sciences, 3, 40-49 (in Russian)

How to cite: Nekrylov, N., Hovakimyan, S., Moritz, R., Bergemann, C., Hambaryan, K., and Meliksetian, K.: Abovyan – an enigmatic Kiruna-type apatite-magnetite deposit in Armenia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3046, https://doi.org/10.5194/egusphere-egu24-3046, 2024.

The occurrence of Zn-Pb(-Cu-Fe) mineralization in the northern Sila Massif (Calabria), primarily in Longobucco (LGB) and Fonte Argentila (FAR) areas, is not a novelty (e.g., Fregola et al., 2023). However, the genesis of this mineralization and its relation to the geological evolution of the Sila Massif are still unknown. These issues are addressed in the present study. Detailed mineralogical and geochemical analyses were carried out on ore-samples collected from mineralized faulted bodies within the granodiorite of the Sila batholith. The mineral association, common to both areas, consists of sphalerite (Sp), as main ore-mineral, galena (Gn), quartz (Qz) and calcite (Cal). Samples from the FAR site also contain chalcopyrite (Ccp), pyrite (Py), and fluorite (Flr). Mineral composition and microstructures were characterized using SEM, EPMA and m-Raman spectroscopy techniques. In addition, trace element distribution in sphalerite and chalcopyrite were determined with LA-ICP-MS. The sphalerite is Fe-poor (Fe up to 11.3 wt%; 0.21 mol% FeS) and shows the associated color and chemical zonings mainly due to variations in Fe concentrations. The following trace elements have been identified in sphalerite: Mn, Co, Cu, Ga, Ge, Ag, Cd, In, Sn, Sb, Hg, Tl, Pb, Bi. The reconstructed paragenetic sequence comprises five growth stages for both areas. During stage-1, precipitation of massive, light-colored and Fe-poorer Sp1 occurred, whereas in stage-2 a darker, Fe-richer Sp2 formed in association with euhedral Qz1. The latter shows color and chemical zonings related to variations in Al, Na, K, Ca content. Fracturing characterized stage-3, along with precipitation of massive Cal (in LGB) and Flr (in FAR). The calcite in LGB hosts synchysite, with grain sizes between 20 and 60 µm, and ΣREE (Ce, La, Y, Nd, Sm, Pr, Gd, Dy) ranging from 2.40 to 42.6 wt%. Stage-4 was characterized by diffuse recrystallization of colorless Sp3 and Qz2. During the stage-5 an almost pure Gn, Ccp and Py formed at the expense of the previous minerals. Formation temperatures ranging between 150 and 200°C were derived for Sp1 and Sp2 using the GGIMFis sphalerite geothermometer (Frenzel et al., 2016). These predicted values will be compared with those obtained from ongoing fluid inclusion analyses. Anyway, such low formation temperatures are also supported by the Zn/Cd (195–267), Ga/In (190–596), and In/Ge (0.24–1.20) average ratios in the sphalerite, indicative of a low-temperature ore-forming fluid. Our mineralogical and geochemical results are comparable with those of either the vein-type or the MVT deposits, although the examined mineralization in the northern Sila Massif occur in a different geological context and registers slightly higher temperatures than those typical of the MVT deposits (that is, 100–150°C).

How to cite: Ciccolella, A., Festa, V., Ruggieri, G., Schingaro, E., Tursi, F., Ventruti, G., and Fregola, R. A.: The Zn-Pb(-Cu-Fe) mineralization in the northern Sila Massif (Calabria, southern Italy): Genetic constrains from trace element concentrations in sphalerite, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3657, https://doi.org/10.5194/egusphere-egu24-3657, 2024.

The Western Anti-Atlas belt is globally renowned for hosting metallic ore deposits, including large copper-silver deposits. The Ouarmdaz-Chikh Imi Nrfi area is located southwest of the Precambrian Ighrem inlier, approximately 168 km east of the city of Agadir. This area is known for its stratiform copper-silver mineralization along the contact between the Precambrian basement and the infracambrian cover. This level is of particular interest on a regional scale because of its spatial extension.

The Igherm inlier comprises Precambrian basement formations, including polygenic conglomerates, red sandstones, and andesitic lava. The cover consists of a siltstone-sandstone series capped by Tamjout dolomites and lower limestones. These terrains are cross-cut by the Ighrem doleritic dyke and are affected by extremely discrete brittle deformation and very pronounced ductile deformation, indicating highly mineralized zones.

This area is characterized by polymetallic mineralization with copper, silver, lead sulfides, and iron oxides. These mineralizations are hosted in the infracambrian cover. Paragenesis is stratiform, vein-type, or in geodic cavities. The mineralized structures are mainly oriented NE–SW, with a dip of 30° to 50° toward the southwest.

The paragenetic study of mineralization has enabled us to identify the different metallic phases and propose a paragenetic succession. The primary paragenesis comprises pyrite, chalcopyrite, bornite, and galena. The primary mineral phases underwent metasomatism, giving rise to secondary parageneses represented by chalcocite, covellite, malachite, azurite, and iron oxides, including hematite and goethite. This mineralization features complex textures (myrmekitic, collomorphic, carrie, and continent).

The analytical data by (ICP) indicated relatively high levels of copper and copper oxide (<25.4%). Silver with concentrations ranging from 7 to 176 g/t, demonstrates a positive correlation with copper.

Scanning electron microscopy (SEM) analysis revealed that the highest copper concentrations were recorded in the malachite-rich zones. Iron and copper oxides of the delafossite type have also been identified in association with dolomite.

Keywords: Western Anti-Atlas, Ighrem, Ouarmdaz-Chikh Imi Nrfi, Mineralization, stratiform, Copper-silver deposits, ICP, SEM.

How to cite: Ayoub, A., Saida, A., Yousra, M., Mohamed, E., Mohamed, A., Lhoussayn, O., Rachid, T., Youssef, Z., Mohamed, S., and Zouhir, B.: The Ouarmdaz region: A new copper-silver potential of the Igherm inlier (Western Anti-Atlas, Morocco)., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5713, https://doi.org/10.5194/egusphere-egu24-5713, 2024.

The geological factors controlling Li abundances in the mantle and mantle-derived magmas rising through the continental lithosphere, as well as their implications for Li ore genesis in the shallow crust, are still under debate. Here, we look from the mantle source perspective at those mechanisms that may boost the Li inventory in continental arc magmas, by characterizing a set of sub-arc mantle xenoliths from the southern Andes (Coyhaique volcanic field, western Patagonia). The mineral trace element signatures and oxygen fugacity estimates (FMQ > +3) in these peridotite xenoliths are consistent with those expected for a mantle wedge fluxed by oxidizing, subduction-related silicate melts rich in slab-derived volatile components. However, our data support that subduction-related metasomatism did not enhance significantly the Li inventory of the sub-arc lithospheric mantle, at odds with the generally claimed major role of slab-derived fluids in enriching Li in the supra-subduction mantle wedge. Major and trace element compositions of minerals also record transient thermal and chemical anomalies fingerprinting the interaction with OIB-type alkaline melts, which percolated through the shallow (7.2-16.8 kbar) and hot (952-1054 °C) mantle wedge in response to the opening of an asthenosphere slab window and ridge collision. This alkaline metasomatism produced exceptionally high Li abundances (6-15 ppm) in metasomatic clinopyroxene, promoting the generation of a Li-rich and fertile lithospheric mantle wedge. A numerical model suggests that low degrees (< 10%) of partial melting of this alkaline-metasomatized sub-arc lithospheric mantle generates primitive melts having Li abundances (⁓13 ppm) much higher than average subduction-zone basalts. Extreme differentiation by fractional crystallization of these Li-rich magmas may provide an effective pathway for enhancing the fold enrichment process required for a magmatic rock to effectively source ore deposition in the shallow arc crust.

How to cite: Schettino, E., González-Pérez, I., Marchesi, C., González-Jiménez, J. M., Grégoire, M., Gervilla, F., Blanco-Quintero, I., Corgne, A., and Schilling, M.: A metasomatized lithospheric mantle contribution to the genesis of Li-rich magmas in slab-window settings, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8251, https://doi.org/10.5194/egusphere-egu24-8251, 2024.

The Otjosondu area contains one of the most important Manganese deposit of Namibia. An exploration campaign in the late 2000’s acquired an extensive dataset (fieldwork, drillholes, geophysics and petrological data) to improve our knowledge of the deposit. The geological history is however, ill-studied and the deposit is classically attributed to banded iron formation of the Sturtian Chuos formation from the Damara sequence.

Using samples from drillholes, we here provide Pressure-Temeprature-time constrain using thermodynamic modelling and LA-ICP-MS U-Pb ages on zircon, monazite and apatite to decipher the regional metamorphic evolution. Our petrological study concludes that the Otjosondu Mn deposit is affected by a HT-MP metamorphic event, estimated at ~670°C and 0.6. This HT-MP metamorphism is associated to a strong ductile deformation with development of shear zones, and multiple-scale intense folding. These metamorphic and structural features totally preclude the description of a typical sedimentary sequence, on which the previous authors had based their classical lithostratigraphic comparison. We date this HT metamorphic event at ca. 525Ma using U-Pb ages on monazite in paragneisses and in a granite, and U/Pb ages on zircon in the same granite.

Detrital U-Pb ages on zircon reveal that the maximum deposition age is at ca. 540Ma. This excludes the attribution of the gneisses surrounding the Mn deposit to the Sturtian Chuos Formation challenging the prevailing interpretation of this ore deposit. Detrital U-Pb ages on zircon also record older magmatic events at ca. 620 and 585 Ma, which are well-known regionally, but were not previously documented in the Otjosundu area. Finally, U-Pb ages on apatite (490+/-3Ma) highlight a late thermal event (hydrothermal or static metamorphism). Results of this study illustrates the importance of characterizing the entire geological history of an ore deposit, to improve the future exploration.

How to cite: Plunder, A., Le Bayon, B., Cagnard, F., Poujol, M., Cogné, N., and Bailly, L.: Back to the Otjosondu manganese deposit: an integrated structural, petrological and geochronological study, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9186, https://doi.org/10.5194/egusphere-egu24-9186, 2024.

Antimony is an incompatible chalcophile element. Its concentration in the Earth’s mantle was estimated to ~0.14 μg g^-1 Sb [3], while the Sb estimates for the upper continental crust scatter between 0.2 to 0.8 μg g^-1 [4]. Recent analytical advances in the precision and accuracy of stable Sb isotope analyses allowed to assess the potential of δ¹²³Sb_NIST3102a as a proxy for ore forming [1] and oxidation/weathering [2] processes. Application of this proxy, however, is limited by the lack of knowledge of the Sb isotope composition of the Earth and its fractionation during high-temperature cycling.

Here, we present bulk rock Sb isotopic compositions of a range of basic and ultrabasic USGS reference materials (n = 12) from different settings and a suite of basic rocks (n = 3) from Hawaii, aiming to estimate the Sb isotopic composition of the bulk silicate Earth (BSE).  The sample suite shows an isotopic range (all values expressed hereafter as δ¹²³Sb_NIST3102a) from -0.10 to +0.27 ‰. Two of the fifteen samples display an isotopic composition of > +0.24 ‰ which are, however, marked by low Nb/U, Ce/Pb, and elevated Zr/Nb, indicating crustal contamination in the magmatic source [5]. Excluding these two samples our analyzed sample suite shows an average δ¹²³Sb_NIST3102a value of +0.01 ± 0.08‰ that we suggest as a preliminary reference value for the Sb isotope composition of the bulk Earth. Our findings furthermore provide first insights for Sb isotope variations in high-temperature rocks that may be related to recycling processes in the mantle.

[1] Zhai et al. (2021), GCA. 3016, 84-97.

[2] Ferrari et al. (2023), Chem. Geol. 641, 121788.

[3] McDonough and Sun (1995), Chem. Geol. 120, 223-253.

[4] Majzlan and Filella (2023), Geochem. In press, 126072.

[5] Hofmann et al. (1986), EPSL. 79(1-2), 33-45.

How to cite: Kaufmann, A., Lazarov, M., Horn, I., Majzlan, J., and Weyer, S.: Antimony isotope composition of the bulk silicate Earth, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10027, https://doi.org/10.5194/egusphere-egu24-10027, 2024.

The European Kupferschiefer Province contains multiple sediment-hosted stratiform copper (SSC) deposits and has been mined for many centuries. The mineralized rocks of the Kupferschiefer are stratabound and hosted by a stratigraphic succession of Late Permian terrestrial sandstones (Rotliegend Formation) and transgressive marine mudstones and limestones (Zechstein Formation). The formation of the Kupferschiefer deposits has been described by various genetic models, which primarily differ in terms of the timing of ore stage sulfide formation relative to host rock deposition (i.e. syn-genetic vs. epigenetic). In this study, samples from two drill cores in the Spremberg-Graustein Kupferschiefer deposit (eastern Germany) are described. Reflected light and scanning electron microscope (SEM) petrography has been used to determine key paragenetic relationships and in situ sulfur isotope values of pyrite and chalcopyrite (secondary ion mass spectrometry; SIMS) have been generated to determine pathways of sulfide formation. The extensive replacement of carbonate and feldspar by ore stage sulfides provides evidence that hydrothermal activity post-dated the formation of diagenetic phases in all units. The highly negative δ³⁴S values of pyrite (–41.9‰ to –35.7‰) and chalcopyrite (–38.9‰ to –34.5‰) indicate that reduced sulfur was generated via open system organoclastic sulfate reduction (OSR). The indistinguishable δ³⁴S_chalcopyrite values preserved in the Rotliegend sandstones and Zechstein mudstones suggest a common origin of sulfides in distinct lithologies. To reconcile the petrographic evidence of host rock replacement with the isotopic evidence of open system sulfate reduction requires an external source of bacteriogenic sulfur, most likely in the form of a low temperature sulfur rich brine. The infiltration of low temperature brines transporting bacteriogenic sulfur is a key feature of genetic models in other sediment hosted systems (e.g., Irish Zn Ore Field). If this model is applied to the Kupferschiefer district, exploration programs should target subbasins with evidence of low temperature brine circulation from marginal sedimentary facies.

How to cite: Magnall, J., Liu, Y., Gleeson, S., and Rocholl, A.: The origin of the Kupferschiefer mineralization (eastern Germany): constraints from petrography and analysis of stable sulfur isotopes of pyrite and chalcopyrite, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10634, https://doi.org/10.5194/egusphere-egu24-10634, 2024.

The absence of primary sulfides challenges the interpretation of metal ore genesis, particularly where ore is hosted within several separate stratigraphic horizons. In the Timna Valley, S Israel, copper ore bodies occur mostly in Cambrian and Cretaceous sandstones and rarely in the underlying late Neoproterozoic Timna igneous complex (TIC), as secondary Cu-sulfides in veins and nodules and more abundantly as Cu-hydroxides. The timing and setting of copper mineralization in the TIC and its relation to the sedimentary ore are unknown. Quartz phenocryst-hosted fluid inclusion assemblages (FIA) in quartz porphyry (QP) stock and dykes are associated with sulfide inclusions of pyrite, chalcocite, and chalcopyrite, indicating a magmatic-hydrothermal genetic relationship. Mineralization-associated fluid inclusion assemblages (FIAs) in QP are: (FIA.a) <12 wt% NaCl eq., CO2 vapor-rich arrays with and homogenization temperatures (Ths) of 270­­­­­­­­­­­­–500°C; ­­­­­(FIA.b) immiscible 30–35 wt%. NaCl eq. aqueous liquid and a CO2 vapor-rich fluid trapped at 193–266°C; (FIA.c) secondary H2O liquid-rich arrays (0-11 wt% NaCl eq.), Th of 115–256 ⁰C. Mineralization-associated zircon and rutile in QP yielded U–Pb ages of ~595 Ma, overlapping alkaline felsic dykes in S Israel. Rapid cooling below 220°C is evident by average rutile (U–Th)/He age of 595 ± 46 Ma found in QP and adjacent quartz monzonite and porphyritic granite. Zircon (U–Th)/He ages record Carboniferous heating at 180 ⁰C ≤ T ≤ 220 ⁰C and hydrothermal alteration. This indicates temperatures in the TIC did not exceed ~180 ⁰C after the Carboniferous. Primary copper mineralization in the TIC is attributed to QP emplacement, during A-type granite intrusions, possibly scavenging copper and other metals from earlier calc-alkaline crust. This was followed by lower temperature (<220°C) hydrothermal events.

How to cite: Elhadad, A., Bar, E., Vapnik, Y., Haviv, I., Kylander-Clark, A., Golan, T., and Katzir, Y.: The Setting and Timing of Copper Mineralization in the Timna Igneous Complex, southern Israel., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-11597, https://doi.org/10.5194/egusphere-egu24-11597, 2024.

The Paleoproterozoic (c. 2054 Ma) Sakatti Cu-Ni-PGE deposit is one of the most significant metal discoveries in Europe during the 21^st century with the resource of 44.4 Mt @ 1.9 wt.% Cu, 0.96 wt.% Ni, 0.05 wt.% Co, 0.64 g/t Pt, 0.49 g/t Pd and 0.33 g/t Au. The deposit lies in the municipality of Sodankylä, northern Finland, that is emerging as a Ni-Cu-PGE mining camp, already including the Kevitsa Ni-Cu-PGE mine (Boliden) and several subeconomic magmatic sulfide deposits. The Sakatti ore mainly consists of massive Ni- and Cu-dominated ore lenses (Cu/Ni < 0.5, Pd/Pt ≈ 4, and Cu/Ni ≈ 9, Pd/Pt ≈ 1, respectively). These massive ore shoots are surrounded by a veil of Cu-rich disseminated sulfides (Cu/Ni ≈ 7, Pd/Pt < 1) hosted by olivine cumulates and coarse-grained gabbronorites. In the upper parts of the deposit, massive ore lenses grade into Cu-rich stockwork vein ore (Cu/Ni > 100, Pd/Pt ≈ 2) that partly sits in olivine cumulates and partly in flanking komatiitic lavas. The sulfide deposit is underlain by tens of meters thick anhydrite-carbonate rock unit that represent a Paleoproterozoic meta-evaporite based on carbon and sulfur isotope values. Sulfate-bearing sediments are a legitimate source of sulfur for magmatic Ni-Cu-PGE deposits, as demonstrated by major Ni-Cu(-PGE) deposits, e.g., Noril‘sk-Talnakh (RUS), Bushveld and Uitkomst Complexes (RSA), Munali in Zambesi belt (ZMB) and Quill Creek Intrusive Complex in Slave Craton (CAN).

The ore and host rocks in Sakatti exhibit chaotic magma-sulfate interaction textures, salt crystal pseudomorphs, and crustal contamination trends that are evident in major and trace element geochemistry as well as in isotope geochemistry. The Sakatti deposit contains typical indicator minerals such as marialitic scapolite, albite, chlorapatite, pargasite and phlogopite-biotite resulting from the interaction of magma with sulfate evaporites and/or saline brines derived after dissolution of evaporites. Sulfur isotope ratio from different ore types is rather uniform (δ³⁴S_CDT c. 3-4 ‰) suggesting a mainly non-mantle source for sulfur and isotopically homogeneous sulfide phase, either due to homogeneous source composition or complete mixing of sulfur from multiple sources before its precipitation as sulfide. Assimilation of sulfate and conversion to a sulfide ore is a complex process likely facilitated by a co-existing fluid phase due to the degassing caused by assimilation. Recent melting experiments using Noril’sk picrite and sedimentary rocks have demonstrated how sulfate incorporation into mafic-ultramafic magmas by diffusion does not unequivocally lead to precipitation of sulfides but instead to a sulfate-rich magma, that further requires interaction with a reductant such as carbon-rich sediments, before sulfides may precipitate. Recognizing the role of sulfates in formation of a magmatic sulfide ores is detective work, as pristine sulfate evaporites tend to vanish from the geological record in structurally complex Precambrian metamorphic terrains, leaving only cryptic marks to the mineral deposits, including skarns, Cl-alterations, pseudomorphs, breccias and heat-resistant sulfates (e.g., anhydrite).

How to cite: Höytiä, H., Peltonen, P., Halkoaho, T., Karhu, J., and Lamberg, P.: Role of sedimentary sulfates in the genesis of massive Ni-Cu-PGE deposits - constraints from the Sakatti Cu-Ni-PGE deposit, Northern Finland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15044, https://doi.org/10.5194/egusphere-egu24-15044, 2024.

The Börzsöny mountain is part of the neogene Inner Carpathian volcanic belt and located in north of Hungary, close to the Central Slovakian Volcanic Field. The andesitic-dioritic rocks of the mountain host ore deposits of a porphyry hydrothermal system, but most of these ore bodies are barely known.

The complex volcanic history of the Börzsöny took place in the middle miocene. According to the K/Ar dating of the host and overlapping volcanic rocks, the ore formation is related to the first, mostly explosive and finally intrusive stage of the volcanic activity (15.2 – 14.8 Ma) (Korpás et. al, 1998). The elevated position of the crystalline basement in the central part of the Börzsöny showed by different geophysical measurements and endomagmatic rock inclusions suggest the presence of a large dioritic intrusive body at a depth of about 2.5 km from the surface (Csillagné Teplánszky et. al., 1980). The ore deposits discovered until now fall on a ring-shaped structure left over from the uplift (Korpás et. al, 1998).

The best investigated part of the ore complex is the central epithermal ore deposit called Rózsabánya. During geological research of two decades, a weak porphyry copper deposit was discovered below Rózsabánya at a depth of about 1.2 km (Csillagné Teplánszky et. al., 1980).

Based on ore petrography and SEM measurements, the multistage paragenesis of Rózsabánya started with the mineralization of arsenopyrite with some cobalt content, native gold and bismuth. This first stage was followed by a Zn-Cu-Pb-Ag-Sn-In mineral association mostly related to galena, sphalerite and chalcopyrite, that could be found as remnants in later minerals in almost all cases. In the third stage, the former minerals were partly consumed by a large amounts of pyrrhotite, which altered to different degrees to pyrite±marcasite. The next stage is characterised by galena, chalcopyrite and sphalerite mineralization, without Sn and In. The mentioned minerals are often replaced by pyrite±marcasite, Bi-sulphides and –sulphosalts, occasionaly arsenopyrite (with some cobalt and nikkel content) and finally by siderite. In some cases, where the alteration of pyrrhotite to pyrite and marcasite was intensive, the mineralization is associated with chloritization.

Based on the observed textures and paragenesis of Rózsabánya, some of the important thermodynamic parameters of the system could be estimated. After the mineralization of a low sulphidation state epithermal mineral assemblage, increasing temperature (around 400 – 450 °C according to the mol fraction of FeS of the pyrrhotite) and/or decreasing sulphur and oxigene fugacity caused the pyrrhotite mineralization. With cooling and elevation of sulphur and oxigene fugacity, the system crossed the pyrrhotite-pyrite reaction line, the sulphidation state of the system changed to intermediate and native gold and bismuth were partly dissolved during this process. While the bismuth re-precipitated as native bismuth, bismuth-sulphide and –sulphosalts (at slightly acidic-neutral pH), gold was carried to longer distances.

The presence of geochemical barriers where gold could be precipitated, the cause of the mentioned changes in the hydrothermal system and the relation of these processes to the deep level and the surrounding epithermal deposits are the subjects of further research.

How to cite: Mészárosné Turi, J.: Geological and geochemical investigation of ore bearing deposits in the Börzsöny mountains, N-Hungary, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15759, https://doi.org/10.5194/egusphere-egu24-15759, 2024.

Volatiles, such as H₂O, S, Cl and CO₂, play a crucial role in regulating volcanic emissions and contribute significantly to the genesis of ore deposits. However, a comprehensive understanding of their role presents a significant challenge due to the intricate task of quantifying the volatile budget and assessing the timeframe linked to magma ascent and volatile exsolution in ore systems.

Apatite, Ca₅(PO₄)₃(F,Cl,OH), stands out as a well-established repository of various volatile species (H₂O, CO₂, S, halogens) in addition to numerous trace elements, making it an excellent mineral to study the volatile budget of magmas. When encapsulated in zircon, apatite inclusions can preserve a unique record of the abundance of volatile ore-forming constituents, eliminating potential influences from diffusion, degassing, and alteration effects associated with late-stage melts and/or hydrothermal fluids.

Our investigation focuses on thoroughly examining such inclusions, alongside groundmass apatite from the Escondida porphyry Cu-Mo±Au district in Northern Chile, which represents one of the most significant high-grade porphyry copper districts in the world. The ore-forming magmatism of the Escondida district took place in the framework of the protracted late Eocene-Oligocene arc magmatic activity, favouring the emplacement of multiphase porphyry stocks.

To resolve the volatile budget of the melt/fluid responsible for the Cu-Mo±Au mineralization in Escondida, we selected a suit of minimally altered samples from mineralized felsic-intermediate igneous intrusions as well as barren counterparts that are spatially associated with the copper mineralization but do not contain metals in sufficient quantity to be extracted and sold at a profit.

The employed multi-microanalytical approach on apatite (SEM-BSE-CL imaging, EPMA, δ³⁴S by SIMS) and the host zircon (Ti-in-zircon geothermometry, U-Pb geochronology), allowed us to determine:
a) the concentrations of halogens in the melt, which contribute to our understanding of the initial, optimal volatile composition for high-grade copper mineralization; b) the pathway and relative timing of volatile exsolution during the magmatic-hydrothermal stage; c) the hydrothermal volatile record of apatite associated with the mineralization stage.

Our work provides new insights into the role of volatiles in arc magmatic settings, demonstrating their potential in shaping economically viable deposits, a crucial cornerstone for a sustainable and environmentally conscious future.  

How to cite: Consuma, G., Kemp, A., Martin, L., Tattich, B., Hagemann, S., and Fiorentini, M.: The role of volatiles in forming high-grade porphyry Cu deposits: learnings from apatite inclusions in zircon, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19743, https://doi.org/10.5194/egusphere-egu24-19743, 2024.

Single-stage partial melting modeling of meta-sediments or extreme fractional crystallization is inadequate for producing melts with the required Li content (>5000 ppm) for spodumene saturation. Therefore, multi-stage partial melting or fractional crystallization processes have been simulated to achieve the necessary Li content. However, these modeling approaches have overlooked the phenomenon of liquid immiscibility, which has been widely observed in the formation of spodumene-rich granitic pegmatites through studies of melt/fluid inclusions. In this study, we investigate the contribution of liquid immiscibility to the enrichment of lithium in granitic pegmatites by conducting elemental micro-analysis and melt inclusion Raman mapping on multi-stage apatite (Ap) samples from the Dangba large spodumene pegmatite deposit (NW China). The apatite samples are categorized into magmatic Ap1, transitional Ap2, hydrothermal Ap3a, and Ap3b based on the presence of exclusive melt, coexisting melt/fluid, liquid-rich, and vapor-rich fluid inclusions, respectively. The observed increase in Li content from Ap1 (median 43.4 ppm) to Ap2 (median 92.1 ppm) can be attributed to melt-melt immiscibility and subsequent fluid exsolution, as evidenced by the occurrence of coexisting water-rich/-poor melt and fluid inclusions. Furthermore, the significant surge in Li content from Ap2 to Ap3a (median 364 ppm) may result from fluid-fluid immiscibility, supported by the presence of coexisting liquid- and vapor-rich fluid inclusions, complementary negative (Ap3a) and positive (Ap3b) Eu anomalies in the chondrite-normalized rare earth element (REE) patterns, and the lowest Li contents found in Ap3b (median 12.3 ppm) among all apatite types. Considering the partition coefficients of Ap-melt (D_Li^Ap/melt < 0.05) and Ap-fluid (D_Li^Ap/fluid << 0.05), both the melts and fluids associated with Ap2 and Ap3a contain sufficient Li content for spodumene saturation. In conclusion, our findings highlight the significant role of liquid immiscibility in the extreme enrichment of lithium during the formation of granitic pegmatites.

How to cite: Chen, X.-D. and Chen, B.: Extreme enrichment of lithium in granitic pegmatite by liquid immiscibility, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20409, https://doi.org/10.5194/egusphere-egu24-20409, 2024.

The Allumiere-Tolfa district is located approximately 60 kilometers northwest of Rome (Italy) and has been characterized by a long mining history for base metals (Pb, Fe), alunite and kaolinite mineralizations dating from prehistoric times (Field & Lombardi, 1972).

These deposits are genetically associated with the emplacement in arc setting of a Plio-Pleistocene volcanic dome consisting of latites and rhyolites, which intruded sedimentary carbonate and siliciclastic country rocks. The intrusive event first produced contact metasomatism of the limestones, and lately triggered hydrothermal activity, which caused a widespread epithermal alteration of the volcanic rocks, resulting in the alteration of the volcanic rocks and emplacement of polymetallic proximal association of Hg-Sb, Pb-Cu, Fe, Zn, Ag, Ba-Sr, F and distal U, Th, Ce, La, Be, Ba, Sr mineralizations (Masi et al., 1980, Della Ventura & Patanè, 2020).

The present work is part of a bigger project investigating various geological features of the Allumiere-Tolfa district (Marchesini et al., 2023) and aims to deepen previous knowledge and investigate in detail the nature of the polymetallic mineralizations of the area. Samples, collected in old pits and outcrops, were analyzed through various techniques: optical microscopy, X-ray diffraction, SEM-EDS analysis, and chemical analysis.

In the area, it was possible to identify distinct alteration facies, residual silica, advanced argillic and argillic facies, with specific ore minerals. The residual silica facies is commonly sulfide-bearing, containing pyrite, As-pyrite, cinnabar, with sphalerite, galena and chalcopyrite. In the advanced argillic facies, pyrite is disseminated in between the aggregates of planar crystals in veins and cavities. Pyrite is also associated with smectite and dickite in the argillic alteration zone. The metasomatized carbonates contain several sulfides such as pyrite and cinnabar with molybdenite, Sr-sulfates, thorutite, thorianite and fluorite. Supergene alteration affected this epithermal assemblage bringing to the formation of gossans with Fe-oxy-hydroxides and secondary sulfides. Preliminary bulk-rock chemical analyses report trace to ultra-trace concentrations of Au.

The identified alteration zones and ore minerals in outcropping rocks indicate low-temperature ore-forming conditions, similar to those occurring in epithermal ores (Simmons et al., 2005), suggesting that possibly the mineralized system extends in depth.

References

Della Ventura G. & Patanè A., 2020. Le miniere dei Monti della Tolfa-Allumiere. Memorie Descrittive Della Carta Geologica D’Italia 106, 23-32.

Field C. & Lombardi G, 1972. Sulfur Isotopic Evidence for the Supergene Origin of Alunite Deposits, Tolfa District, Italy. Mineral. Deposita (Berl.) 7, 113-125.

Marchesini B., Tavani S., Mercuri M., Mondillo N., Pizzati M., Balsamo F., Aldega L., Carminati E., 2023. Structural control on the alteration and fluid flow in the lithocap of the Allumiere-Tolfa epithermal system. Journal of Structural Geology, 105035.

Masi U., Ferrini V., O’Neil J. R. & Batchelder J.N., 1980. Stable Isotope and Fluid Inclusion Studies of Carbonate Deposits from the Tolfa Mountains Mining District (Latium, Central Italy). Minerl. Deposita (Berl.) 15, 351-359.

Simmons S.F., White N.C. & John D.A., 2005. Geological Characteristics of Epithermal Precious and Base Metal Deposits. Economic Geology 100th Anniversary Volume, 485-522.

How to cite: Corrado, F., Solomita, G., Balassone, G., Mormone, A., Marchesini, B., Tavani, S., Carminati, E., Piochi, M., and Mondillo, N.: The mineralizations of the Allumiere-Tolfa District (Central Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16622, https://doi.org/10.5194/egusphere-egu24-16622, 2024.