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The presence of thick (>100 m) and electrically conductive (< 10 Ω.m) ground cover is a major impediment in mineral exploration of deep resources. Iron-oxide copper gold (IOCG) systems in Australia are often associated with a pronounced potential field anomaly, depending on the oxidation state of iron, but the gravity and magnetic field signatures have little vertical resolution unless constrained by drill hole petrophysics. Additionally, IOCG systems have deep magmatic sources, with their conductivity anomalies extending at least to the lithospheric mantle. The Vulcan IOCG prospect lies about 30 km northeast of the Olympic Dam IOCG mine and is defined by a significant gravity anomaly associated with brecciated haematite beneath 850 m of sedimentary cover sequences. To image the physical properties and structural geometry of the Vulcan IOCG prospect, a 100-site broadband MT and passive seismic array was deployed in a 1 km grid over a 9 by 9 km area. Three-dimensional inversion of MT responses resolve structure in three distinct domains. Firstly, broad limestone-quartzite-shale stratigraphy (1–30 Ω.m) in the 850 m cover is delineated in resistivity and corresponds well with changes in shear-wave velocity. Secondly, the region of brecciated haematite below the cover sequences is shown to have lower resistivity (< 60 Ω.m) than surrounding country rock (> 100 Ω.m). Thirdly, a more electrically conductive (< 30 Ω.m) vertical zone that extends > 5 km is imaged a few kilometers to the northeast of the Vulcan haematite breccia, and appears to be linked by a region of low shear-wave velocity in the depth range 1–2 km. Two-dimensional inversion of more regional MT responses along a 200-km line passing through the Vulcan prospect suggest this vertical region of low resistivity links to the lower-crust with anomalous resistivity of < 60 Ω.m in a similar way as imaged beneath the Olympic Dam mine. It is suggested that this conductive region is associated with graphite precipitated from magmatically derived CO2-rich fluids cooling in a reducing environment. [ABSTRACT FROM AUTHOR]

As most outcropping and shallow mineral deposits have been found, new technology is imperative to finding the hidden critical mineral deposits required for the renewable energy transition. One such seismic technique, called ambient noise tomography (ANT), has shown promise in recent years as a low cost and low environmental impact passive method of three-dimensional (3D) imaging of shear-wave velocity structure of the Earth. Over the last twenty years the method has been well-established in academia to image crustal and regional scale geological features but has seldom been used at the mineral exploration deposit-scale. In this paper we show the application of seismic ANT at an IOCG deposit in South Australia under more than 750 m of sedimentary cover. A 100-site survey in a 10 by 10 grid with site spacing of 1 km, using 3-component nodal seismometers with a natural-frequency of 5 Hz, was conducted over a two-week period. Data were inverted to generate a 3D velocity model to a depth of 2 km. When compared to drillholes in the survey area, the tomographic model delineates cover sequence lithologies and the depth of crystalline basement. A velocity anomaly in the basement has characteristics of a potential IOCG deposit and is aligned with a gravity anomaly due to brecciated haematite. The results of the paper indicate that ANT is a useful tool for deep cover mineral exploration that can potentially expedite the discovery of new deposits. [ABSTRACT FROM AUTHOR]

Abstract\nKEY POINTSThe Dugald River Shear Zone is a structurally complex, anastomosing shear zone that hosts high-grade Zn mineralisation within the Dugald River Slate. The Dugald River Zn–Pb–Ag mine is situated within the Mount Isa Inlier, Australia and developed through two phases of mineralisation with high-grade Zn mineralisation intimately associated with the development of the brittle–ductile Dugald River Shear Zone. The first phase of mineralisation occurred during the regionally extensive, D2 ductile fold and axial planar cleavage forming event and resulted in the development of a sulfide horizon. This horizon was a preferential site for strain partitioning during early D4 ductile deformation, which resulted in transposition-related concentration and thickening of a sulfide horizon marking the second phase of mineralisation. The Dugald River Shear Zone developed during D4 wherein strain rate incompatibilities between a ductile-deforming sulfide horizon and the brittle-deforming Dugald River Slate resulted in the development of a Riedel shear zone. A high-resolution 3D model of the shear zone was constructed from robust drilling and mapping datasets in which releasing and restraining bends highlight the thickening and thinning of ore lenses, respectively. The 3D model with detailed structural analysis and observations allows for predictive modelling of dilational zones within throughgoing Y-shears, which are prospective sites for remobilisation of high-grade Zn sulfides as the ore body developed coevally with progressive shearing.Detailed structural analysis provides 3D modelling parameters and exploration vectors.The Dugald River Shear Zone developed as an evolved Riedel shear network during dextral transpression.Understanding the shear zone’s 3D geometry and kinematics allows for predictive modelling of ore lens distribution and identification of dilational zones, which are crucial for exploration and mining strategies. [ABSTRACT FROM AUTHOR]

This review article examines the critical role of remote sensing techniques in analysing land cover and its implications for copper deposit exploration. The study aims to provide a comprehensive review of current research and technical advancements in using remote sensing to characterise land cover in copper-rich areas. It draws attention to the complex relationships that exist between subsurface copper mineralisation, surface vegetation, and soil types by combining case studies and modern literature. Integrating satellite imagery, geospatial data, and advanced analytical methods, this review demonstrates how remote sensing can effectively identify and map areas with high potential for copper deposits. Furthermore, it discusses the challenges and opportunities associated with remote sensing applications in geological studies and offers insights into future research directions to enhance mineral exploration and environmental management practices. [ABSTRACT FROM AUTHOR]

Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in 2017. Sulfides and oxides in the samples were separated, and Cu and Zn isotope compositions were analyzed. Results show that the ranges of δ65Cu values of the bulk sediments, sulfides, and oxides were 0.36‰–2.46‰, -0.21‰–1.10‰, and 0.68‰–1.52‰, respectively. The δ65Cu values of sulfides in four samples (46II-14, 46II-30, 46III-06, and 46II-09) were relatively low (-0.21‰–0.50‰), corresponding to the δ65Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge (nMAR), suggesting that the sulfides in the sediments were originated from collapsed dead chimney mainly. While the δ65Cu values of the other two samples (46III-02 and 46III-08) were relatively high (1.10‰–0.96‰), corresponding to the δ65Cu values for active hydrothermal chimneys sulfides in nMAR, which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal plume. Because of the high density of sulfide particles, they tended to settle near the hydrothermal vents first. Therefore, high δ65Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal field. The δ66Zn values of hydrothermal sediments and sulfides ranged 0.11‰–0.43‰ and 0.29‰–0.67‰, respectively. In the four samples from the Xunmei hydrothermal field, a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio, showing that the greater the distance from the mineralized spot, the heavier the Zn isotope composition as seen in two samples (46II-30 and 46II-14) of the Xunmei-3 spot. This result aligned with the findings of Wilkinson et al. (2005) and Baumgartner et al. (2023), suggesting that the lower the Zn isotope composition, the closer it is to the hydrothermal vent. However, in the Xunmei hydrothermal field, the Zn isotope composition in the other two samples (46III-02 and 46III-06) showed the opposite trend. This indicated that there might be an active hydrothermal vent near the sampling location of sample 46III-02. This observation aligned with the Cu isotope analysis results. This study showed that Cu-Zn isotopes are good indicators for understanding the formation mechanisms of hydrothermal sediments and for locating active hydrothermal vents. [ABSTRACT FROM AUTHOR]

Maseve Mine is located in the western limb of the Bushveld Complex, recognized as the largest layered igneous intrusion in the world. The study shows results from surface (SP1, SP2, and SP3) and tunnel (T3a, T3b, and TP4b) reflection seismic profiles, totaling 4150 m. Tunnel seismic data were acquired using a seismic landstreamer and spiked geophones with 5 m receiver and shot spacing, as well as a sledgehammer for shots due to space constraints and safety. The profiles, 10–50 m above mineral deposits, crossed major geological structures. Surface seismic profiles used cabled systems and wireless sensors with 5 m and 10 m receiver spacing, respectively, and a 500 kg drop hammer as a source with 10 m shot spacing. Despite high noise levels from mine infrastructure and power cables, a careful processing workflow enhanced target reflections. Interpretation was constrained using borehole data, geological models, and 2D/3D seismic modeling. The processed data exhibit gently dipping reflections associated with faults and dykes, imaging the target mineralization (Merensky Reef and Upper Group 2) and a possible extension. Tunnel seismic experiments demonstrated the application of seismic methods using in-mine infrastructure, while surface experiments proved efficient, illustrating small-scale seismic surveys' capability to image the subsurface, adding value in active mining environments for exploration with cost-effective seismic equipment. [ABSTRACT FROM AUTHOR]

Disruptions in the minerals supply chain play a central role in defining the future stock of minerals; therefore, an in-depth analysis of the outcomes and variables affecting exploration is required. In comparative terms, the exploration of critical minerals and major minerals presents geological and technical differences; thus, exploration budgets for critical minerals should be expected to depart from those observed in other minerals. In this context, the main goal of this paper is to contrast how exploration budgets differ between critical and major minerals when considering a set of key variables. We take a multivariate statistical analysis approach based on firm-level budget exploration data to show four key findings: exploration budgets allocated for critical minerals remain consistently lower than major minerals even when controlling for other factors. Moreover, they present a higher sensitivity to fluctuations in commodity prices. Besides, the investment made by larger companies in critical minerals significantly lags behind those made by junior companies. Additionally, the focus of exploration activity for critical minerals predominantly lies in the earlier stages of the exploration process. We expect these initial results to be used as a step forward to facilitate the discussion about exploration policies and, consequently, the reliability of the supply chain. [ABSTRACT FROM AUTHOR]

The estimation of the distribution of ferromanganese crusts (FMCs) is determined using the threshold of backscatter intensity of the multibeam echo sounder in ground-truth data; however, this is not accurate. This study developed a method to quantitatively estimate the distribution of FMCs and thickness of the surface sediment (TSS) by determining the relationship between topographic features, backscatter intensity using statistical analyses. Thus, the exposure of FMCs and TSS was quantitatively evaluated with accuracies of 17% and 2.5 m, respectively. This method can efficiently estimate distributions of FMC and TSS of entire seamounts for the benefit of future mineral explorations. [ABSTRACT FROM AUTHOR]

Mineral resources are an important material basis for the development of human society and have become a topic of global concern in the 21st century. This paper adopts the method of bibliometric analysis to summarise the research progress of global remote sensing in the field of mineral exploration from 2000 to 2022 and gives an outlook on the future research direction. In this study, we used bibliometric analysis to provide a comprehensive overview of the research progress of global remote sensing in the field of mineral exploration from 2000 to 2022, and to provide an outlook on future research directions. We analysed 37,977 publications related to this period covering 185 countries, 2646 journals 16,328 institutions 25,170 funding agencies, and 114,746 authors.

The Dschang area has substantial mineral and geological exploration potentialities. However, its basement is unclear due to lack of studies on mineral and lithology mapping, and other mineralization indices. The lithological units and potential hydrothermal alteration zones in the Dschang area are investigated here using remote sensing; geographic information systems (GIS); and statistical analysis which are essential method for geological exploration. Landsat 9 OLI, ASTER data using False Color Composites (FCC), Band Ratios (BRs), Principal Component Analysis (PCA), Spectral Angle Mapper (SAM), fuzzy-logic methods, and field observations are used to identify the rocks units and potential mineralization. The integration o these multiple methods allowed the identification of orthogneiss, granites and basalts with iron-oxides, hydroxyl and ferrous bearing as potential mineralization in the Dschang area. The Evaluation of the fuzzy membership of each alteration mineral from Landsat 9 OLI and ASTER data indicates that the highest favorability index varies from 0.8 to 1 indicating a rating index related to iron mineralization. From the statistical analysis of the geochemical data, the calcic, alkaline-calcic, and metaluminous to weakly peraluminous I-type character of the Dschang granites prove their parent magma was fertile for mineralization in Rare Earths, Cu, Sn, Mo, Zn, and Pb. In addition, analysis of lineaments illustrated three structural directions in the area (ENE-WSW to NE-SW, N-S to NNE-SSW, and NW–SE). The innovative aspect of this research is the integration and processing of Landsat 9 OLI, Fuzzy, ASTER, statistical geochemical analysis of previous data, and field investigations, which allows for the identification of rock units and potentially mineralized rock formations and defining exploration targets as well. [ABSTRACT FROM AUTHOR]

Mineral exploration combined with prospectivity mapping has become the standard process for utilising mineral exploration data. Nowadays, most techniques integrate multiple layers of information and use machine learning for both data-driven and knowledge-driven approaches. This study introduces a novel and generalised methodology for comparing different layers of information by using superpixels instead of pixels to identify similarities. This methodology provides an enhanced statistical representation of regions, facilitating and enabling effective comparisons. Three different statistical distance measures were considered: Kullback–Leibler divergence, Wasserstein distance and total variation distance. We apply the proposed process to data from the Antofagasta region of northern Chile, a well-known area for metallogenic belts, that contain notable copper reserves. Each metric was used and compared, resulting in different similarity maps highlighting interesting mineral exploration areas. The study results lead to the conclusion that the proposed methodology can be applied at different scales and helps in the identification of areas with similar characteristics. [ABSTRACT FROM AUTHOR]

Abstract This study interprets aeromagnetic data from the Tizi n'Test area in the High Atlas massif of Morocco, aiming to gain insights into its litho-structural architecture and implications for mineral exploration and mining. We employed six different analytical techniques to the residual magnetic field data, including reduction to the pole (RTP), upward continuation, total horizontal derivative, Tilt angle, Centre for Exploration Targeting (CET) analysis, and Euler deconvolution. Our analyses differentiated the study area into three magnetic domains: the eastern Ouzellarh block, characterized by positive anomalies, a central domain characterized by a negative magnetic signature demarcating the transitional zone between the Anti-Atlas and the High Atlas separated by the Ouchden fault: and the western domain, represented by the Tichka massif. The application of total horizontal derivative, tilt angle, and a combination of filters in ternary image formats (Tilt angle, upward continuation 1000 + Tilt angle and upward continuation 3000 + Tilt angle) revealed both known and previously unidentified geological lineaments, mapping structural complexity across various orientations (NE–SW, NNE–SSE, E–W, NW–SE, and N–S). The CET grid analysis method unveiled the structural complexity, highlighting the geodynamic evolution of the region. Particularly, the Ouchden fault delineates a magnetic domain divide between the ancient High Atlas and the Ouzellarh block (Anti-Atlas). Furthermore, Euler deconvolution indicated magnetic source depths ranging from 52 m in the western domain of the Tichka massif to 6560 m in the Ouzellarh block. A comprehensive structural scheme, classified by C-A fractal analysis, identified zones favourable for exploration and mining, particularly along the Ouchden fault, Tizi n'Test, NE-SW trending lineaments in the northwestern domain, as well as along the Tichka granite’s margin.

This study utilised lithogeochemistry and stable isotope geochemistry to assess the gold mineralisation in the host rocks of the Abansuoso area. It also studied the isotopic signature of hydrothermally altered and unaltered rocks as a tool for the preliminary prospecting of gold in Ghana’s Birimian belt. The research identified a close association between Au and As, Mo, and W, which is characteristic of orogenic gold deposits. The mineralised and unmineralised rocks show similar content of major and trace elements which suggests that the mineralisation did not significantly affect the primary composition of the mineralised rocks. The concentrations of δ18O (8.9‰ to 17.4‰, n = 22, mean = +13.7‰) and δD (−117 to −33‰, n = 22, mean = −57.9‰) in the rocks are comparable to those from other Birimian regions in Ghana and West Africa. The lack of variation in δ18O suggests a system buffered by rocks, with metamorphic fluid originating from rocks with identical δ18O values. However, the effect of mineralisation on the δD values of rocks is substantially more apparent than its effect on the δ18O values of the rocks.

Successful geophysical exploration projects in the Gucheng–Yaxi area located in Gaochun District, Jiangsu Province, China, have been limited partly due to the complex geological conditions of the area and high artificial noise in data acquired using electrical and electromagnetic methods. In this study, we deployed the new anti-interference spread-spectrum-induced polarization method (SSIP) and the audio-magnetotelluric (AMT) method to detect a copper–polymetallic deposit in the area. Two-dimensional inversion results in the Gucheng–Yaxi area revealed a high chargeability anomalous zone on the SSIP profile that coincided with a zone of moderate resistivity located between two resistor bodies on the AMT profile. A follow-up 1200 m drill hole was established at this high-chargeability, moderate-resistivity zone which encountered polymetallic (copper, lead, zinc, gold, and silver) mineralization at a depth of ≥400 m. Drill hole data analysis showed that mineralization occurred interspaced in the marble rock mass at varying depths. Furthermore, several low-resistivity, weak-chargeability sections were revealed and attributed to Cretaceous sediments and faults. These faults are thought to have played a critical role in the polymetallic mineralization genesis. In summary, this study demonstrated the successful of application of SSIP and AMT in detecting a metallic deposit in an area with high artificial noise. Hence, the geophysical prospection potential of the Gucheng–Yaxi area is great. [ABSTRACT FROM AUTHOR]

The Beishan region is a vital fluorite metallogenic belt in northwest China, characterized by favorable geological conditions for fluorite mineralization. However, being located in the Gobi Desert and affected by shallow cover layers, only a few outcrops can be observed on the surface. Therefore, comprehensive geophysical research is necessary to locate and predict regional metallogenic potential and the spatial distribution of veins beneath the cover. This study conducted a combination of ground magnetic method (GM), induced polarization (IP) surveys, portable gamma-ray (PGR), portable X-ray fluorescence analyses (PXRF), and audio Magnetotelluric (AMT) to conduct comprehensive exploration. The IP and GM effectively identified concealed ore-bearing space distributions and ground PGR- and PXRF-constrained mineralization anomalies, while AMT surveys constructed deep electrical structure models for ore deposits. This approach delineated concealed fluorite deposit locations as well as potential magmatic–hydrothermal migration pathways. Engineering verification confirmed the effectiveness of this method combination. This study established a comprehensive geological–geophysical positioning prediction technique that can serve as a reference for locating and predicting fluorite deposits in shallow-covered areas within the Gobi Desert. [ABSTRACT FROM AUTHOR]

Tourmaline is common in magmatic-hydrothermal deposits, and its composition and boron isotope geochemistry have been widely used to fingerprint the source and evolution of hydrothermal fluids and associated metals. However, whether these chemical or boron isotopic compositions or their combinations can be used as vectors for mineral exploration remains to be explored. In this study, we documented the major and trace element compositions and boron isotopic values of tourmaline along a vertical extension (i.e., 510, 830, 1230 m above sea level, a.s.l.) of the newly discovered porphyry Au mineralization in the Hewan feldspar quartz porphyry, Yixingzhai deposit, to shed light on the evolution of the ore-forming fluid, the mechanisms of Au deposition, and potential indicators for Au exploration. Field observations showed that tourmaline in the Hewan porphyry occurred mainly as orbicules or veins and intergrew with Au-bearing pyrite, hydrothermal quartz, and some clay minerals, indicating a magmatic-hydrothermal origin. Tourmaline sampled from 510 m a.s.l. showed δ11B values (–11.5 to –9.3‰) consistent with those of the average continental crust and tourmaline in magmatic systems, which suggests that the ore-forming fluid was most likely exsolved from the host Hewan porphyry. The δ11B values became heavier upward, reaching –9.9 to –1.5‰ at 830 m and –8.0 to +6.8‰ at 1230 m a.s.l. This boron isotopic variation, integrated with increasing Fe, Mg, Na, Ca, Li, Co, and Sr but decreasing Al, U, Th, REE, Zn, and Pb contents of the tourmaline samples from deep to shallow levels, implies that the initial magmatic fluids were gradually mixed with circulating meteoric water that contained materials leached from peripheral Archean metamorphic rocks and Mesoproterozoic marine sedimentary rocks. Considering the spatial distribution of the Au grade of the porphyry, we propose that a suitable mixing proportion of magmatic and meteoric fluids caused Au deposition and accumulation. We note that tourmaline samples collected from the economic Au zones had much lower and more concentrated δ11B (–11.5 to –3.0‰), Co/(Pb+Zn) (<0.01), and Sr/ (Pb+Zn) (0.27 to 1.07) values than those in low-grade or barren zones. Coeval plutons and breccia pipes, where tourmaline also occurs, are well developed inside and outside the Yixingzhai Au mine. We suggest that the obtained parameters can potentially be used as proxies for further Au exploration in this region. This study highlights the feasibility of using the chemical and isotopic compositions of tourmaline for mineral exploration. [ABSTRACT FROM AUTHOR]

The discovery of the Northern Copper Belt in SW Poland is a result of an extensive exploration project with a key role played by various science-related methods. The project relied on mapping the distribution of mineral zones in the entire Fore-Sudetic Monocline, a unit known for its occurrences of Cu-Ag orebodies. This approach involved the examination of historical drill cores from over 400 oil and gas holes in this area, with the collection of samples for laboratory analyses. A close relationship was confirmed between the distribution of orebodies and the transformation of organic matter. Rock-Eval pyrolysis was also performed on selected samples. The tests of rock specimens were accompanied by the reprocessing of historical gravimetric and seismic surveying results. Field magnetotelluric surveying was also performed in certain areas. This phase resulted in the identification of areas with a high probability of finding the best ore, allowing for the initiation of the drilling stage. So far, 37 exploratory boreholes have been drilled in those locations, nearly all of them with highly positive results. The Northern Copper Belt consists of three deposits, Nowa Sól, Mozów, and Sulmierzyce North, along with numerous prognostic areas distributed therebetween. The future production of copper, silver, and the accompanying valuable elements presents a chance to provide the whole of Europe with a new plentiful supply of those critical raw materials. [ABSTRACT FROM AUTHOR]

This study interprets aeromagnetic data from the Tizi n'Test area in the High Atlas massif of Morocco, aiming to gain insights into its litho-structural architecture and implications for mineral exploration and mining. We employed six different analytical techniques to the residual magnetic field data, including reduction to the pole (RTP), upward continuation, total horizontal derivative, Tilt angle, Centre for Exploration Targeting (CET) analysis, and Euler deconvolution. Our analyses differentiated the study area into three magnetic domains: the eastern Ouzellarh block, characterized by positive anomalies, a central domain characterized by a negative magnetic signature demarcating the transitional zone between the Anti-Atlas and the High Atlas separated by the Ouchden fault: and the western domain, represented by the Tichka massif. The application of total horizontal derivative, tilt angle, and a combination of filters in ternary image formats (Tilt angle, upward continuation 1000 + Tilt angle and upward continuation 3000 + Tilt angle) revealed both known and previously unidentified geological lineaments, mapping structural complexity across various orientations (NE–SW, NNE–SSE, E–W, NW–SE, and N–S). The CET grid analysis method unveiled the structural complexity, highlighting the geodynamic evolution of the region. Particularly, the Ouchden fault delineates a magnetic domain divide between the ancient High Atlas and the Ouzellarh block (Anti-Atlas). Furthermore, Euler deconvolution indicated magnetic source depths ranging from 52 m in the western domain of the Tichka massif to 6560 m in the Ouzellarh block. A comprehensive structural scheme, classified by C-A fractal analysis, identified zones favourable for exploration and mining, particularly along the Ouchden fault, Tizi n'Test, NE-SW trending lineaments in the northwestern domain, as well as along the Tichka granite’s margin. [ABSTRACT FROM AUTHOR]

Geophysical electromagnetic survey methods are particularly effective in locating conductive mineral deposits or mineralization zones in a mineral resource exploration. The forward modelling of the electromagnetic responses over such targets is a fundamental task in quantitatively interpreting the geophysical data into a geological model. Due to the ubiquitous irregular and complex geometries associated with the mineral rock units, it is critical that the numerical modelling approach being used is able to adequately and efficiently incorporate any necessary geometries of the Earth model. To circumvent the difficulties in representing complex but necessary geometry features in an Earth model for the existing mesh-based numerical modelling approaches (e.g., finite element and finite difference methods), I present a meshfree modelling approach that does not require a mesh to solve the Maxwell's equations. The meshfree approach utilizes a set of unconnected points to represent any geometries in the Earth model, allowing for the maximal flexibility to account for irregular surface geometries and topography. In each meshfree subdomain, radial basis functions are used to construct meshfree function approximation in transforming the differential equations in the modelling problem into linear systems of equations. The method solves the potential function equations of the Maxwell's equations in the modelling. The modelling accuracy using the meshfree method is examined and verified using one magnetotelluric model and two frequency-domain controlled-source models. The magnetotelluric model is the well-known Dublin Test Model 2 in which the spherical geometry of the conductor in the shallow subsurface may pose as a challenge for many numerical modelling methods. The first controlled-source model is a simple half-space model with the electric dipole source for which analytical solutions exist for the modelling responses. The second controlled-source model is the volcanic massive sulphide mineral deposit from Voisey's Bay, Labrador, Canada in which the deposit's surface is highly irregular. For all modellings, the calculated electromagnetic responses are found to agree with other independent numerical solutions and the analytical solutions. The advantages of the meshfree method in discretizing the Earth models with complex geometries in the forward modelling of geophysical electromagnetic data is clearly demonstrated. [ABSTRACT FROM AUTHOR]

Laser-induced breakdown spectroscopy (LIBS) is a type of optical emission spectroscopy capable of rapid, simultaneous multi-element analysis. LIBS is effective for the analysis of atmospheric gases, geological fluids, and a broad spectrum of minerals, rocks, sediments, and soils both in and outside the traditional laboratory setting. With the recent introduction of commercial laboratory systems and handheld analyzers for use outside the laboratory for real-time in situ analysis in the field, LIBS is finding increasing application across the geosciences. This article first overviews the LIBS technique and then reviews its application in the domain of mineral exploration and ore processing, where LIBS offers some unique capabilities. [ABSTRACT FROM AUTHOR]

The airborne electromagnetic system MobileMT exploits natural fields in a broadband frequency range with offset measurements of magnetic and electric field variations. It was introduced in 2018 and has since been developed in various configurations, each tailored to meet the demands of different exploration tasks, varied terrains, and geoelectrical conditions and support time-domain data with controlled primary field sources. There are four distinct airborne systems: the original MobileMT; the lighter configuration, MobileMTm; the configuration for a drone carrier, MobileMTd; and the innovative time-domain AFMAG hybrid, TargetEM. The paper describes the technical features of each system, their differences and inherent strengths, the optimal usage conditions, and insights into their applications under different conditions across various exploration tasks. Several field case studies are provided to support the natural field electromagnetics capabilities of recovering geological structures in a wide depth range, beginning from the near surface, and address the impact of parasitic IP effects on time-domain data. [ABSTRACT FROM AUTHOR]

Paleoproterozoic (2.05 Ga) komatiites are widespread in the Central Lapland Greenstone Belt (CLGB), northern Finland. Close association with sulfur (S)-rich country rocks and spatiotemporal connection with the Cu-Ni(-PGE) deposits of Kevitsa and Sakatti make these komatiites interesting targets for sulfide deposit exploration. We provide whole-rock geochemical data from Sattasvaara komatiites and combine it with literature data to form a geochemical database for the CLGB komatiites. We construct a model for the komatiites from adiabatic melting of the mantle source to fractional crystallization at crustal conditions. Using MELTS, we calculate three parental melts (MgO = 20.6–25.7 wt%) in equilibrium with Fo92, Fo93, and Fo94 olivine for the CLGB komatiites. Based on REEBOX PRO simulations, these parental melts can form from a single mantle source by different pressures and degrees of melting when the potential temperature is 1575–1700 °C. We calculate ranges of S contents for the parental melts based on the different mantle melting conditions and degrees of melting. We use Magma Chamber Simulator to fractionally crystallize the parental melt at crustal conditions. These simulations reproduce the major element oxide, Ni, Cu, and S contents from our komatiite database. Simulated Ni contents in olivine are compatible with literature data from Kevitsa and Sakatti, hence providing a baseline to identify Ni-depleted olivine in CLGB komatiites and related intrusive rocks. We show that fractional crystallization of the komatiitic parental melt can form either Ni-rich or Cu-rich sulfide melt, depending on the initial Ni and S content of the parental melt. [ABSTRACT FROM AUTHOR]

This study utilizes domain adaptation to enhance the integration of diverse geoscience datasets, aiming to improve the identification of ore bodies. Traditional mineral exploration methods often face challenges in merging different geoscience data types, which leads to models that do not perform well across varying domains. Domain adaptation is a deep learning strategy aimed at adapting a model developed in one domain (source) to perform well in a different domain (target). To adapt models trained on detailed, labeled drilling data (source) to interpret broader, unlabeled geophysical data (target), Domain-Adversarial Neural Networks (DANNs) were applied, chosen for their robust performance in scenarios where the target domain does not provide labels. This approach was indirectly validated through the minimal overlap between regions identified as candidate ore and borehole locations marked as host rocks, with qualitative validation provided by t-Distributed Stochastic Neighbor Embedding (t-SNE) visualizations showing improved data integration across domains. [ABSTRACT FROM AUTHOR]

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The attractiveness of mineral investments across countries and regions worldwide can be judged through various measures, each with its strengths and weaknesses. The purpose of this paper is to scrutinize the Fraser Institute's ranking of mining jurisdictions, which builds on eliciting the perceptions of industry representatives around the world through an annual survey. The analysis takes stock in the growing scholarship on country performance indicators and concludes that due to the low response rate and the lack of clear definitions of some of the underlying concepts (e.g., political stability), there are reasons to question both the reliability and the validity of this survey. There could also exist incentives among exploration companies to "game" the rankings. For these reasons, the ranking outcomes do not constitute a meaningful scorecard that countries can employ to improve their mining-related policies. However, despite these deficiencies, the Fraser Institute's survey often enjoys relatively uncritical media attention. It even sets in motion a political "rankings game" in which the mining companies, governments, and other organized groups choose to participate. There is an urgent need for a more reliable and unbiased survey approach, including the consideration of alternative—complementing—measures for assessing investment attractiveness in the mining industry. [ABSTRACT FROM AUTHOR]

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Abstract The main coal reserves in Brazil are located in the southern region, where the most important coalfield, including the Candiota mine, is found. The mineral exploration and mine planning programs of the companies mining these coal deposits are generally restricted to drilling data and cores, despite the exploratory potential of geophysical methods in coal prospecting. This study aims to investigate the ability of the seismic method known as Multichannel Analysis of Surface Waves (MASW) to identify coal seams in the Candiota area. The MASW method allows obtaining a layer model composed of a low-velocity (blind) layer and/or relatively thin (hidden) layer from the surface wave dispersion curves. The hidden and blind layer problems are pitfalls of the traditional seismic refraction method and the geological settings related to coal seams may encompass both problems. In addition, the Candiota mine has conditions favorable for applying the MASW method due to the shallow depths of the coal seams. The study was based on the analysis of synthetic seismic data generated from a 3-layer conceptual model of the Candiota deposit. The dispersion curves of the fundamental mode of the Rayleigh surface waves were generated and the effects of each of the parameters of the seismic model were evaluated, as well as the relationship between the parameters through objective function tests. A new inversion algorithm capable of obtaining the true model was implemented. The results obtained from the application of the inversion algorithm demonstrated the potential of the MASW method in identifying coal seams from S-wave profiles and proves it to be a powerful tool for coal mineral exploration programs.

Abstract This study introduces a rapid and efficient inversion algorithm designed for the interpretation of self-potential responses originating from mineralized and ore sources and hydrothermal activity, specifically addressing spherical, vertical, and horizontal cylindrical structures. The algorithm leverages local wavenumber and correlation imaging techniques to enhance accuracy in modeling. The correlation factor (C f value) is crucial in this approach, calculated as the correlation between the local wavenumber of the measured self-potential field and that of the computed field. The algorithm identifies the maximum correlation C f value (C F -max) as indicative of the optimal true model parameters. To validate the proposed algorithm, it was applied to three theoretical examples—one with contamination from regional background and another with multiple sources with and without different types of noises (random Gaussian and white Gaussian noises). Additionally, the approach was tested on three distinct real field cases related to mining, ore investigation and hydrothermal activity in India, Germany and USA. Through a comprehensive analysis of results from theoretical and real-world scenarios, including comparisons with different available data and literature information, the study concludes that the method is effective, applicable to multiple sources, accurate, and does not necessitate prior knowledge of the source shape. This algorithm presents a promising advancement in the field of self-potential interpretation for mineral exploration and geothermal exploration.

The Youjiang Basin in China is the world's second-largest concentrated area of Carlin-type Au deposits after Nevada, USA, boasting cumulative Au reserves nearing 1000 t. This study examined the recently unearthed Lintan Carlin-type Au deposit within the Youjiang Basin. Factor analysis and association rule algorithms were used to identify exploration vectors and indicators essential for navigating this promising geological territory. In the Lintan mining area, the geological strata encompass the Triassic Bianyang, Niluo, and Xuman formations comprised clastic rocks, followed by the deeper Permian Wujiaping Formation with massive carbonate rocks. The orebodies are restricted to the F14 inverse fault, cutting through the Xuman Formation, with an additional F7 fault between the Wujiaping and Xuman formations. A total of 125 rock samples from the F14 fault and a representative cross-section were analyzed for 15 elements (Au, Ag, As, Bi, Cd, Co, Cu, Hg, Mo, Ni, Pb, Sb, Tl, W, and Zn). The elements were divided into four groups based on cluster and factor analysis. Group 1 (Co, Cu, Zn, Ni, Tl, W, and Bi) was mainly enriched in the Xuman, Niluo, and Bianyang formations controlled by sedimentary diagenesis. Group 2 (Au, As, Hg, and Sb) was concentrated in the F14 and F7 faults, representing Au mineralization. Group 3 (Pb, Ag, and Mo) was mostly enriched near the F14 and F7 faults, displaying a peripheral halo of Au mineralization, and was probability controlled by ore-forming hydrothermal activities. Group 4 (Cd and Mo) exhibited extreme enrichment along the periphery of the F7 fault. This pattern indicates the presence of a substantial hydrothermal alteration zone surrounding the fault, likely influenced by ore-forming hydrothermal processes. Additionally, Pb, Ag, Cd, Mo, and W are considered essential indicators for ore formation besides Au, As, Sb, Hg, and Tl. Twelve effective association rules were derived using the association rule algorithm, which can aid in discriminating Au mineralization. The spatial distributions of the 15 elements indicated that the F14 fault is the main ore-bearing fracture zone, while the F7 fault serves as the ore-conducting structure, channeling ore-forming fluids into the F14 fault. Faults between the Wujiaping and Xuman formations, along with their associated reverse faults, present potential prospecting targets both within and outside the Lintan Au deposit in the Youjiang Basin. Exploration geochemical data can be fully utilized by combining factor analysis and association rule algorithms, offering key guidance for prospecting Carlin-type gold and similar deposits. [ABSTRACT FROM AUTHOR]

Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Remote sensing satellite imagery consistently provides valuable and frequent information, enabling the exploration of mineral resources across immense, remote and harsh domains. Recent developments in spaceborne hyperspectral remote sensing have opened avenues to support diverse remote sensing applications, particularly in the realm of mineral exploration. This study evaluates the capabilities of the PRecursore IperSpettrale della Missione Applicativa (PRISMA) hyperspectral satellite data for mapping alteration minerals using the Matched Filtering Unmixing (MFU) approach in the Sar-e-châh-e-shur, Birjand, Iran. Minerals such as richterite, augite, psilomelane, ilmenite, kaolinite, smectite, mirabilite, muscovite, and chlorite were identified using the vertex component analysis (VCA) technique. Subsequently, alteration mineral maps of the study area were generated using a matched filtering technique. Additionally, through the integration of X-ray diffraction (XRD) analysis, thin section examination, geochemical study of stream sediments, and interpretation of geological maps, potential alteration mineralization zones were delineated in the study area. Ultimately, the validation process, which included comparing the maps with the findings derived from the PRISMA remote sensing study, was conducted using the normal score equation. Thus, our results yielded a normalized score of 3.42 out of 4, signifying an 85.71% agreement with the regional geological characteristics of the study area. The results of this investigation highlight the substantial potential of the PRISMA dataset for systematic alteration mineral mapping and consequent exploration of ore minerals, specifically in challenging and inaccessible terrains. [ABSTRACT FROM AUTHOR]

Apatite, as a common accessory mineral found in magmatic–hydrothermal deposits, effectively yields geochemical insights that facilitate our understanding of the mineralization process. In this research, multiple generations of magmatic and hydrothermal apatite were observed in the Hongshan porphyry–skarn Cu–Mo deposit in the Yidun Terrane in SW China. The geochemical compositions of the apatite were studied using in situ laser ablation–inductively coupled plasma mass spectrometry and an electron probe microanalysis to understand the magmatic–hydrothermal processes leading to ore formation. The apatite (Ap1a) occurs as subhedral to euhedral inclusions hosted in the phenocrysts of the granite porphyry. The Ap1b occurs later than Ap1a in a fine-grained matrix that intersects the earlier phenocrysts. Increases in F/Cl, F/OH, and F/S and decreases in ΣREE and (La/Yb)N from Ap1a to Ap1b suggest the exsolution of a volatile-rich phase from the magma. The skarn hosts three types of hydrothermal apatite (Ap2a, Ap2b, and Ap3), marking the prograde, retrograde, and quartz–sulfide stages of mineralization, respectively. The elemental behaviors of hydrothermal apatite, including the changes in Cl, Eu, As, and REE, were utilized to reflect evolutions in salinity, pH, oxygen fugacity, and fluid compositions. The composition of Ap2a, which occurs as inclusions within garnet, indicates the presence of an early acidic magmatic fluid with high salinity and oxygen fugacity at the prograde skarn stage. The composition of Ap2b, formed by the coupled dissolution-reprecipitation of Ap2a, indicates the presence of a retrograde fluid that is characterized by lower salinity, higher pH, and a significant decrease in oxygen fugacity compared to the prograde fluid. The Ap3 coexists with quartz and sulfide minerals. Based on studies of Ap3, the fluids in the quartz–sulfide stage exhibit relatively reducing conditions, thereby accelerating the precipitation of copper and iron sulfides. This research highlights the potential of apatite geochemistry for tracing magmatic–hydrothermal evolution processes and identifying mineral exploration targets. [ABSTRACT FROM AUTHOR]

This study introduces a rapid and efficient inversion algorithm designed for the interpretation of self-potential responses originating from mineralized and ore sources and hydrothermal activity, specifically addressing spherical, vertical, and horizontal cylindrical structures. The algorithm leverages local wavenumber and correlation imaging techniques to enhance accuracy in modeling. The correlation factor (Cf value) is crucial in this approach, calculated as the correlation between the local wavenumber of the measured self-potential field and that of the computed field. The algorithm identifies the maximum correlation Cf value (CF-max) as indicative of the optimal true model parameters. To validate the proposed algorithm, it was applied to three theoretical examples—one with contamination from regional background and another with multiple sources with and without different types of noises (random Gaussian and white Gaussian noises). Additionally, the approach was tested on three distinct real field cases related to mining, ore investigation and hydrothermal activity in India, Germany and USA. Through a comprehensive analysis of results from theoretical and real-world scenarios, including comparisons with different available data and literature information, the study concludes that the method is effective, applicable to multiple sources, accurate, and does not necessitate prior knowledge of the source shape. This algorithm presents a promising advancement in the field of self-potential interpretation for mineral exploration and geothermal exploration. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet Plateau, abundant in mineral resources, is a treasure trove for geological explorers. However, exploration has been hindered by the presence of dense vegetation, weathering layers, and desert cover, particularly in the North Qaidam region. As a result, there is an urgent need to develop efficient geochemical composition methods. In a study of stream sediment geochemical data from the Lüliangshan area of the North Qaidam, the log-ratio transformation was used for data processing, Robust Factor Analysis (RFA) was used for model construction, and the spectrum–area (S-A) model was used for anomaly separation. The outcomes identified two distinct groups of element combinations associated with mineralization. The first group consisted of Au + Ag + Pb + Sb + Hg linked to tectonic-altered rock-type Au (antimony) deposits, while the second group consisted of Cu + Zn + Co and was closely associated with Cu-Ni sulfide deposits. The S-A fractal filtering technique amplified weak anomalies and minimized the area of anomalies against strong backgrounds. The study successfully detected substantial Cu mineralization in the source areas of geochemical anomalies in the Lüliangshan region. Consequently, the log-ratio–RFA–S-A fractal model has been proven to be an effective combination of methods for identifying and extracting geochemical anomalies from stream sediment samples and for mineral exploration in covered areas. [ABSTRACT FROM AUTHOR]

Mineral exploration has increasingly targeted areas covered by in situ or transported overburden for shallow to deep-seated orebodies. It remains critical to develop better means to detect the surficial chemical footprint of mineralized areas covered by thick regolith. In such settings, plant geochemistry could potentially be a useful exploration tool, as different plant species have varying degrees of tolerance to metal enrichment in the soil. This review provides insights into the geological and geochemical controls on metal accumulation patterns in soil–plant systems of the Central African Copperbelt. In addition, it highlights the opportunities for integrating the geochemistry of terrestrial plants in emerging exploration technologies, identifies research gaps, and suggests future directions for developing phytogeochemical sampling techniques. This review was conducted using reputable online scholarly databases targeting original research articles published between January 2005 and March 2023, from which selected articles were identified, screened, and used to explore current advances, opportunities, and future directions for the use of plant geochemistry in sediment hosted Cu–Co exploration in the Central African Copperbelt. Various plant species are recognized as ore deposit indicators through either independent phytogeochemistry or complementary approaches. In the Central African Copperbelt, the successful application of hyperaccumulator species for phytoremediation provides the basis for adopting phytogeochemistry in mineral exploration. Furthermore, current advances in remote sensing, machine learning, and deep learning techniques could enable multi-source data integration and allow for the integration of phytogeochemistry. [ABSTRACT FROM AUTHOR]

This paper introduces an original approach to the joint inversion of airborne electromagnetic (EM) data for three-dimensional (3D) conductivity and chargeability models using hybrid finite difference (FD) and integral equation (IE) methods. The inversion produces a 3D model of physical parameters, which includes conductivity, chargeability, time constant, and relaxation coefficients. We present the underlying principles of this approach and an example of a high-resolution inversion of the data acquired by a new active time domain airborne EM system, TargetEM, in Ontario, Canada. The new TargetEM system collects high-quality multicomponent data with low noise, high power, and a small transmitter–receiver offset. This airborne system and the developed advanced inversion methodology represent a new effective method for mineral resource exploration. [ABSTRACT FROM AUTHOR]

Copyright of East China Geology / Huadong dizhi is the property of Editorial Department of East China Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Geophysical electromagnetic survey methods are particularly effective in locating conductive mineral deposits or mineralization zones in a mineral resource exploration. The forward modelling of the electromagnetic responses over such targets is a fundamental task in quantitatively interpreting the geophysical data into a geological model. Due to the ubiquitous irregular and complex geometries associated with the mineral rock units, it is critical that the numerical modelling approach being used is able to adequately and efficiently incorporate any necessary geometries of the Earth model. To circumvent the difficulties in representing complex but necessary geometry features in an Earth model for the existing mesh-based numerical modelling approaches (e.g., finite element and finite difference methods), I present a meshfree modelling approach that does not require a mesh to solve the Maxwell’s equations. The meshfree approach utilizes a set of unconnected points to represent any geometries in the Earth model, allowing for the maximal flexibility to account for irregular surface geometries and topography. In each meshfree subdomain, radial basis functions are used to construct meshfree function approximation in transforming the differential equations in the modelling problem into linear systems of equations. The method solves the potential function equations of the Maxwell’s equations in the modelling. The modelling accuracy using the meshfree method is examined and verified using one magnetotelluric model and two frequency-domain controlled-source models. The magnetotelluric model is the well-known Dublin Test Model 2 in which the spherical geometry of the conductor in the shallow subsurface may pose as a challenge for many numerical modelling methods. The first controlled-source model is a simple half-space model with the electric dipole source for which analytical solutions exist for the modelling responses. The second controlled-source model is the volcanic massive sulphide mineral deposit from Voisey’s Bay, Labrador, Canada in which the deposit’s surface is highly irregular. For all modellings, the calculated electromagnetic responses are found to agree with other independent numerical solutions and the analytical solutions. The advantages of the meshfree method in discretizing the Earth models with complex geometries in the forward modelling of geophysical electromagnetic data is clearly demonstrated.

Mining contributes to an increased tax revenues, export earnings, employment opportunities, infrastructure development, and transfer of technology to the host countries. However, there is a high risk of socio-economic enclaves or environmental damages caused by mining operations which include the release of heavy metals into water and soil resources, air pollution, land degradation, and depletion of vegetation. Mineral exploration is often preoccupied with integrating relevant datasets and utilising various techniques to discover subtle surface indications of mineralisation and usually results in huge disturbances of large surface area and underlying strata including aquifers. These issues with mineral exploration are pronounced in developing countries where the primary goal of many investors is to look for the occurrence of mineral of interest and its economic viability with little or no attention to the associated hydrogeological risk. Hydrogeological Risk Assessment, even though crucial to the development of sound environmental impact assessment for a proposed mineral exploration project, is often not included in mineral exploration activities. This could potentially result in a significant health risk and environmental impact which could negatively impact various communities within the mining areas. In this research, an overview of the various stages involved in evaluating and assessing the hydrogeological risk from the initial exploration stage has been provided. A framework that will enable a short-term to long-term integrated groundwater resources management system into mineral exploration projects have also been developed. This framework would provide valuable information to stakeholders to verify whether a proposed project is likely to be debilitating to hydrogeology in a locality.

Mapping of highly altered zones favorable to mineralization is crucial to finding useful mineral deposits. However, several methods have been used to locate areas subject to weathering processes, including analysis of airborne gamma-ray spectrometry data, which have demonstrated accurate and reliable results. In order to target other promising areas, and ensure the sustainability of bauxite mining, gamma-ray spectrometry was carried out and applied for the first time in the Boke region, located in the north–west of the Republic of Guinea which encompassing the world's famous bauxite district. The results obtained from the K/eU, K/eTh ratios, the F parameter and the potassium map were processed by the fuzzy logic model using ArcGIS software, the model can be used to merge the resulting informative maps into a single mineral prospectivity map, serving as a guide for mineral exploration. Three zones of high mineral prospectivity have been identified, essentially the Ordovician formations at Pita, the Silurian at Telimele and the Devonian at Faro. According to these preliminary prospecting results, the delineated areas contain localities that are probably potential, giving the green light for more advanced prospecting.

Reflectance spectroscopy is a rapid and non-destructive technique for probing the chemical composition of the earth surface. The minerals are characterised by absorption features whose wavelength is function of its crystal chemistry. In the present study, we propose a covariance weighted least square inversion approach to model the wavelength position of the absorption features. The approach takes into consideration the noise in the reflectance spectra and estimates the wavelength position with root mean square value of less than 5 nm for library spectra. The algorithm is then implemented on AVIRIS-NG datasets of Hutti-Maski schist belt to map the spatial variations in wavelength position of absorption features in wavelength range 2290–2360 nm. Sensitivity of model parameters to number of points, effect of number of data points on striping noise and limitations of the proposed algorithm are also discussed. It is observed that the algorithm based wavelength map is smooth and enables identification of gradients in absorption wavelength position. Mapping of such gradients are very important for understanding subtle changes in crystal chemistry due to hydrothermal alteration and possible mineralization. The generated wavelength map can be used in conjunction with alteration mineral assemblage to identify prospective zones for mineral exploration. [ABSTRACT FROM AUTHOR]

In recent years, remote sensing technology has played an important role in geological and mineral exploration, and the extraction of alteration minerals based on multi-source remote sensing data has greatly reduced the range of target areas and time cost in the work. The enhancement and extraction of mineral alteration information in Tibetan Jhule area was carried out based on Landsat-9, ASTER and Sentinel-2 remote sensing data. The feature components in the principal component analysis ( PCA) of multi-source remote sensing data were normalized by linear affiliation function and then superimposed by Fuzzy Gamma operator to map the mineral search target area. The γ parameters were set as 0. 7, 0. 75, 0. 8, 0. 85 and 0. 9 in the experiment, and finally γ = 0. 85 was determined to be relatively good after the experiment. A total of 8 target areas were circled, and the feasibility of the method in target area circling at high altitude was verified by the field survey. Meanwhile, the field investigation results show that the area has developed high sulfur type shallow-forming low-temperature hydrothermal alteration mineral assemblage, which has the potential of porphyry-shallow-forming low-temperature hydrothermal deposits [ABSTRACT FROM AUTHOR]

Some of the high heat production granites in the continental crust have been suggested to be linked with I‐, A‐, and partly S‐type granitoids which aided in the formation of associated polymetallic deposits. Here, we investigate the Shibaogou and Laojunshan plutons in the Luanchuan region, East Qinling Orogen, China, and integrate these with published geochemical information to compute the rate of heat production per unit rock mass (RHP value, unit μW/m3). In addition, we also present RHP contour maps of all the Late Mesozoic granitic plutons in the Luanchuan region, with a view to evaluate the link among the high heat production granites, their petrogenesis and mineralization. The RHP values of granitoids in the Luanchuan region vary from 1.7 to 14.44, with the Nannihu pluton showing the highest RHP peak value of 6.04, whereas the Huoshenmiao pluton has the lowest RHP peak value of 2.59. The RHP values have a positive correlation with the degree of magma differentiation, as suggested that the Nannihu pluton is a highly fractionated I‐type granite and the Huoshenmiao pluton is a quartz diorite. This is also consistent with U, Th and K which are incompatible elements that tend to enter the melt during magma evolution. Furthermore, the higher RHP value intrusions (e.g., Nannihu, Daping) show close genetic links with high economic deposits, whilst the plutons with lower RHP values are generally related to small ore deposits. We envisage that the high heat production granites underwent protracted cooling process, which promote the convection and circulation of hydrothermal fluids, so that ore‐forming materials (e.g., Mo, W) can sufficiently accumulate and precipitate as economic mineralization. This also indicates that these granitoids with relatively higher RHP values have a greater metallogenic potential. The RHP contour mapping results show high RHP value domains ranging from 2.68 to 4.82 in the southeast and northeast segments of the Shibaogou pluton, whereas the RHP values of other regions in this pluton vary from 2.14 to 2.68. In contrast, the high RHP value regions mostly occur within the western and eastern parts of the Laojunshan pluton, and range from 4.91 to 6.21. Other regions in the Laojunshan pluton have low RHP values in the range of 2.69–4.91. A few Mo‐W deposits are mostly hosted in the southeastern part of the Shibaogou pluton, implying that these regions with high RHP values might have higher metallogenic potential. The contour mapping of RHP maximum, minimum, average and peak values of all the Mesozoic granitic plutons in the Luanchuan region also show high value zones within and/or at peripheral regions of the Nannihu ore fields and these segments between the Nannihu and Yuku ore fields, which suggest that these zones likely have high potential for Mo‐W exploration. [ABSTRACT FROM AUTHOR]

Eastern Kerdous demonstrates a polymetallic hydrothermal activity due its association with a paleorelief area. This study focuses on generating a Mineral Potential Map based on Fuzzy Logic Modelling and HyMap-Based input layers. The Relative Absorption Band Depth, Directed Principal Component Analysis, Line Density, and Mixture Tuned Matched Filtering techniques were implemented to perform 20 thematic layers. As a result, three new prospective zones were identified. Fieldwork, petrography, and XRD analysis verified the remote sensing results. Finally, this investigation highlights the significant potential of HyMap imagery for mineral exploration in inaccessible and remote parts of the western Anti-Atlas belt. [ABSTRACT FROM AUTHOR]

In the Anti-Atlas belt, the Saghro massif stands out as the most promising area for exploring bases and precious metals. It serves as a noteworthy example of effectively utilizing various geological layers by employing fuzzy logic operators to predict new targets and identify potential mining zones in this region. This paper demonstrates the integration of geoscience datasets in a GIS system, enabling the identification of significant targets for mineral exploration. The geo-information layers utilized included Neoproterozoic acid volcanic and intrusive rocks, hydrothermal alterations, faults, zones of structural complexity, geochemical anomalies, and mineral occurrences. The results highlighted that the boundary between the Neoproterozoic basement and its Paleozoic cover presents a crucial target for discovering mineral deposits and identifying new polymetallic mineralization zones with significant mining potential. Eight favorable zones have been identified, indicating the presence of Cu–Ag–Pb polymetallic mineralization and Ag–Hg mineralization associated with the late Neoproterozoic acid volcanic rocks of the Ouarzazate group. The outcomes of this study are invaluable for mineral exploration, serving as essential guidance for mining prospectors and advanced metallogenic investigation programs in the northeastern part of the Moroccan Saghro massif. [ABSTRACT FROM AUTHOR]