The northern margin of the Qaidam Basin is an orogenic gold metallogenic belt associated with the Tethyan orogenesis. However, the precise timing of gold mineralization and the compositions of the ore-forming fluids in this region remain enigmatic. Geological observations, mineral assemblages, texture, trace elements, and in situ S isotope analyses of pyrite, and in situ U-Pb dating of rutile in the Qinglonggou gold deposit were carried out to solve the puzzles. The orebodies of the Qinglonggou gold deposit controlled by NW (NNW)-trending faults are dominantly distributed along the contact zone between the Mesoproterozoic Wandonggou Group dolomitic marble and quartz diorite porphyrite. Hydrothermal alteration types include quartz, sericite, chlorite, epidote, and carbonate. Gold mineralization can be classified into three stages: (I) quartz-pyrite (Py1), (II) quartz-pyrite (Py2)-polymetallic sulfides, and (III) quartz-carbonate stages. The Py1 comprises a porous core with galena inclusions and a smooth, regular rim. The rim of Py1 is enriched in Au, As, Cu, Pb, Zn, and Sb, whereas the core is enriched in Au and As. The Py2 is characterized by a microporous core with elevated Au, As, Cu, Pb, Zn, and Sb, in contrast to a smooth, irregular rim with depleted concentrations of these elements. The delta S-34 values of Py2 are 4.2 similar to 5.5 parts per thousand, lower than those of Py1 with values of 5.2 similar to 9.6 parts per thousand. The pyrite from gold orebodies has delta S-34 values of 4.2 similar to 9.6 parts per thousand, which are significantly lower than those from the host rocks (10.0 similar to 14.3 parts per thousand). These variations in pyrite texture and geochemistry can be attributed to the interactions of ore fluids with various lithologies. In situ U-Pb dating of rutile coexisting with Py1 constrains mineralization at 452.0 +/- 4.6 Ma. This study highlights that the Qinglonggou gold deposit belongs to orogenic gold deposits associated with the Proto-Tethyan orogenesis. These findings have practical significance for guiding gold exploration in the northern margin of the Qaidam Basin.

The structural evolution and deformation conditions of ore-controlling shear zones in the large-scale Jinshan orogenic gold deposit were studied through structural mapping, petrographic analysis and electron backscatter diffraction (EBSD) observation. Four distinct deformation events are identified, including pre-mineralisation ductile deformation (D-1 and D-2), syn-mineralisation brittle-ductile shearing (D-3) and post-mineralisation brittle faulting (D-4). Gold-bearing quartz veins are confined to D-3-stage NE-SW-trending shear zones characterised by thrust plus sinistral slip movement under NW-SE-oriented compression. The mineral assemblage includes pyrite, arsenopyrite, chalcopyrite, galena, and native gold associated with quartz-sericite alteration. The quartz can be divided into two groups: pre-mineralisation coarse (>100 & micro;m) grains and gold-related fine (<50 & micro;m) grains. The coarse-grained quartz displays dominant prism and rhomb slip with intermediate- to high-temperature deformation fabrics (400 degrees C-600 degrees C) and has undergone sub-grain rotation recrystallisation after its formation. In contrast, the gold-related quartz distributed along the margins of coarse-grained quartz displays bulging recrystallisation with dominant basal slip, indicating intermediate- to low-temperature conditions (300 degrees C-400 degrees C). The intermediate- to low-temperature gold mineralisation event overprinted earlier intermediate- to high-temperature fabrics. This study highlights that the reactivation of the pre-mineralisation shear zones provided fluid pathways for subsequent auriferous fluid flow and gold deposition.

The mineralization characteristics, geodynamic setting and dynamic driving mechanisms of porphyry-epithermal polymetallic deposits developed along margins of cratonic continental basins remain poorly understood. In this study, the Qibaoshan Cu-Pb-Zn ore district, the Hubu Mo-Pb-Zn and Yangjiayu Cu-Pb-Zn deposits, located along the southern margin of the Jiaolai Basin, were selected as cases for a systematic investigation on their mineralization processes and geodynamic setting by using comparative analyses of hydrothermal alteration, mineral assemblages and geochronological data. The Qibaoshan Cu-Pb-Zn ore district is controlled by regional crypto-explosive breccia pipes and faults, and is characterized by chalcopyrite, galena and sphalerite metal assemblages, accompanied by quartz-sericite and carbonate alteration, resembling intermediate-sulfidation epithermal systems. The Hubu Mo-Pb-Zn deposit is structurally controlled by regional faults and dominated by molybdenite, quartz, sericite and K-feldspar mineral assemblages, representing porphyry-type Mo mineralization. The Yangjiayu Cu-Pb-Zn deposit is characterized by chalcopyrite, galena and sphalerite, with quartz-sericite and carbonate alteration, indicative of a fault-controlled epithermal hydrothermal deposit. Zircon U-Pb isotopic dating yields ages of 117.0 +/- 0.8Ma for the Hubu granitic porphyry and 119. 1 +/- 2. 1 Ma for the Yangjiayu granodiorite porphyry, which are comparable to the 120Ma sub-volcanic complexes in the Qibaoshan ore district. These results suggest that the magmatic events in Qibaoshan, Hubu and Yangjiayu were coeval and related to a common tectono-magmatic process. Integrating our data with previous tectonic studies, we infer that the polymetallic mineralization along the southern margin of the Jiaolai Basin formed in an extensional setting associated with slab rollback or stress-field reorganization of the subducting Paleo-Pacific Plate. Volcanic edifices and faults at the basin margins can serve as regional prospecting indicators, whereas differences in metal assemblages across mineralization zones and specificity of magma and mineralization require further investigation.

Classifying the genetic types of gold deposits is essential for effective exploration. This study focuses on developing a classifier that can categorize the diverse types of gold deposits using the trace element contents of pyrite, the most common sulfide mineral in most of these deposits. Based on 13,624 pyrite trace element records from 9 types of gold deposits worldwide, random forest (RF), support vector machine (SVM) and k-nearest neighbor (KNN) classifiers were constructed and evaluated. Comparative analysis identified the RF classifier as the best performing model, exhibiting superior predictive accuracy and robustness. Model interpretation and geochemical validation employed SHAP (feature importance analysis), Spearman correlation (element associations), and UMAP (dimensionality reduction and visualization). Results show distinct classification of deposit types, confirming pyrite trace elements as reliable genetic indicators. Feature importance analysis highlighted As, Te, and Ag as key discriminators. Pyrite from Carlin and orogenic deposits is rich in As and Au, whereas epithermal and VMS types have moderate-to-low Te, As, and Se. Porphyry-related pyrite is low in Sb, As, and Au. In contrast, SEDEX pyrite is enriched in Te, Se, and Bi, and skarn pyrite shows high Zn but low As and Se. These systematic variations suggest that the trace elements signature of pyrite is primarily controlled by fluid-rock interaction processes during mineralization, which are strongly influenced by the composition of the host rocks.

Disorientation is a common and impactful failure mode in everyday navigation. This paper addresses this issue by modeling Navigation-Lost (NL) scenes as structured interactions between human and environmental factors. We propose the Navigation-Lost Knowledge Graph (NLKG), a conceptual framework that incorporates 24 entity types and 27 relation types, covering subjective perception, travel modes, and objective environmental context (e.g., weather, terrain, road layout). To efficiently populate the NLKG at scale, we develop a triple extraction model— NavLTR —which includes modules for handling nested semantics, hierarchical relations, and urban functional categories. To mitigate data scarcity and anchor evaluation, we create the Navigation-Lost Information Extraction Database (NIED), a comprehensive domain corpus. On extensive benchmarks, NavLTR achieves state-of-the-art performance, with an F1 score of 92.82%, significantly outperforming existing baselines. We demonstrate the practical utility of NLKG in two downstream applications: (i) a prototype question-answering system that surfaces contextual cues to assist navigators and (ii) multi-perspective graph analytics for risk prediction and factor attribution, providing actionable insights for urban wayfinding and spatial design. Collectively, these contributions—the schema, corpus, and schema-aware extractor—lay the foundation for a reproducible framework for NL scene understanding and offer a practical path for transforming unstructured narratives into context-aware geospatial reasoning, benefiting both end users and urban planners.

Getting lost in complex urban environments is common, yet the environmental determinants of the risk of getting lost (RGL) remain poorly quantified. This study develops a multi-scale, data-driven framework that links local visual-perceptual attributes (e.g., sky visibility, scene openness, pedestrian density) with global spatial-structural metrics (e.g., road curvature, road type, land-use pattern) derived from multi-source geospatial data and image semantic segmentation. Using 3303 easy-to-get-lost (E2G) locations and 3303 matched easy-to-navigate (E2N) locations across six urban context types, we employ random forest regression to identify key environmental correlates of RGL. Results reveal strong context dependence alongside consistent cross-cutting mechanisms. In tourist areas, RGL is primarily driven by road curvature and mitigated by higher sky visibility. In transportation hubs, road type, curvature, and building density elevate RGL, whereas clearer guidance signage and more concentrated land use have protective effects. In cultural and business districts, pedestrian density is the dominant driver, with additional amplification from complex road geometry and fine-grained functional mixing. In residential areas, higher sky visibility and scene openness systematically reduce RGL, while greater building density and road curvature increase it. Across contexts, open, legible vistas are generally associated with lower RGL, whereas crowding and path complexity increase disorientation. The proposed framework achieves a peak predictive accuracy of 0.759 in transportation hubs. Although non-causal, these relationships provide an actionable evidence base for embedding wayfinding legibility into transport and urban design, emphasizing visual openness, simplified layouts, demand management, and standardized guidance to support more navigable and sustainable cities.

The integration of machine learning (ML) techniques into mineral prospectivity mapping (MPM) has significantly improved the efficiency of exploration targeting. However, conventional data-driven approaches often insufficiently incorporate geological processes, limiting model interpretability and geological consistency. To address this gap, this study utilized a knowledge–data dual-driven framework for MPM targeting orogenic gold deposits in Guangxi, Southwest China. Geological knowledge of orogenic gold mineral system is explicitly embedded at two levels: (1) feature engineering, with particular emphasis on structural characteristics, especially lineament density, as controlling factor; and (2) training data are formed by positive-unlabeled (PU) samples guided by knowledge. The strategy restricts the selection of negative samples by using structural, stratigraphic and geochemical criteria to reduce sampling bias and enhance geological representativeness. Four representative ML algorithms—random forest, support vector machine, deep neural network, and deep forest (DF)—were systematically evaluated. The results indicated that the DF model achieved the best prediction accuracy, robustness and generalization. Feature importance analysis and SHapley additive explanations revealed that the control sequence is consistent, with structural parameters dominating, followed by geochemical anomalies and stratigraphic units. Independent verification of the strategy in the Youjiang Basin and Qin–Hang Belt—two domains hosting orogenic gold deposits with contrasting geological characteristics—showed that the structural architecture is broadly transferrable, whereas lithological traps and geochemical signatures limit model generalization. Based on the prediction results of the knowledge–data dual-driven DF model, this study identified several new prospective targets in the Youjiang Basin and Qin–Hang Belt, providing clear direction for the next stage of gold exploration. This paper demonstrates that integrating mineral systems knowledge—particularly structural controls and sampling constrains—improves both model interpretability and geological credibility of ML-based MPM, and provides a practical workflow for MPM in structurally complex regions.

The northern margin of the Qaidam Basin is a key Proto-Tethyan collision zone and a prospective orogenic gold metallogenic belt, however, the evolution and source of its ore-forming fluids has long been controversial. The Shengligou gold deposit, a representative deposit in the western segment of the northern margin of the Qaidam Basin, was investigated in this paper through large-scale mapping, petrographic observations, and in situ trace element and sulfur isotope analyses of multi-generation pyrite to constrain this controversy. Three pyrite generations (Py-1, Py-2, Py-3) are identified, including gold-bearing Py-2 (quartz-polymetallic sulfide stage) and Py, (quartz-carbonate stage). While Py-1, aligned with ductile shear foliation and displaying cataclastic texture, is enriched in Co-Ni (averaging 201.9 9 * 10 (- 6) Co, 174.3 3 * 10 (- 6) * Ni ) Furthermore, the Py, exhibits oscillatory zoning, with AuAs--Pb rich cores and Cu-Zn-Sb rich rims, recording dynamic fluid influx that triggered episodic gold deposition; the Py, forms fine-grained disseminations with high Ag (mean 251.5 x 10). The delta(34) values of pyrite at Shengligou range from 1.8% to +3.7% (averaging at 0.29%), suggesting a derivation of ore-forming materials from an enriched mantle source. Systematic Co/Ni decreases (Py1 -> Py3: 1.25 -> 1. 14) and low S/Fe ratios (<1.2) confirm a hydrothermal origin. Se/Te fluctuations track a "low-high-low"f0(2) for path. Gold, transported as Au(HS), at 172 degrees C and incorporated as Au into pyrite, precipitated during multi-fluid events, dominated by mantle-derived fluids in the main stage (Py-2). This study proposes a new exploration model based on the triad of an enriched mantle source, NW-trending ductile-brittle shear zones, and a metamorphosed volcanic sequence, offering a novel framework for gold exploration in the North Qaidam Tethyan orogen.

The fluid sources and genetic mechanisms of the giant Zhaishang gold deposit in the West Qinling Orogen remain debated. This study integrates geological observations with textural, trace element, and in-situ S-Pb isotopic analyses of pyrite to address this issue. Four distinct generations of pyrite (PyI-PyIV) are recognized. The PyI occurs parallel to cleavage and displays porous textures associated with sericite and quartz alteration. The PyI delta 34S values range from +21.0 %o to +25.9 %o in Devonian strata, and from +1.9 %o to +2.9 %o in Permian strata, both of which are interpreted to be of diagenetic origin. The PyII is texturally characterized by porous cores and overgrowth rims, and is associated with calcite-ankerite alteration in Devonian strata (PyII-D) and quartz alteration in Permian strata (PyII-P). The primary gold enrichment is localized in the core of PyII-D and the rim of PyII-P. In the high-grade ores, the PyIII is associated with polymetallic sulfide mineralization and ankerite-siderite alteration, and exhibits distinct core-mantle-rim texture. The PyIII exhibits repeated Au-rich zones in both cores and rims. The PyII-D has delta 34S values of +9.8 %o to +14.0 %o (average = +12.0 %o), and PyII-P ranges from-6.5 %o to-4.2 %o (average = -5.3 %o). The S isotopic signatures of PyII, which are similar to those of global sediment-hosted orogenic gold deposits, together with the Pb isotopic data, collectively support a metamorphic fluid origin. In contrast, the narrow variation of delta 34S values (-2.8 %o to +0.4 %o), Pb isotopic signatures and high Co/Ni ratios, are indicative of magmatic fluids for high-grade gold mineralization. The PyIV is associated with native gold and LMCE minerals (low-melting point chalcophile elements) in calcite veinlets. Combined with the LMCE-rich characteristics of PyIII, the dissolution-reprecipitation of pyrite driven by magmatic-hydrothermal fluids, which remobilized both LMCE elements and Au, is considered the primary mechanism for high-grade mineralization. We conclude that multistage mineralization involving metamorphic and subsequent magmatic fluid superimposition led to the formation of the Zhaishang deposit, a model that may also apply to other gold systems in the West Qinling Orogen.

This study investigates the pre- to syn-mineralization rupture styles of ore-controlling faults in Jiaodong gold province to address the controls of structural geometry on gold localization. Using 2D finite element models in ANSYS Workbench, we numerically simulated the fracture formation and evolution of the Sanshandao and Jiaojia Fault Zones, which host over 3000 tons of gold. They were categorized into two segments based on dip angle: 15°–20° and 30°–50°. During pre-mineralization compression setting, the low-angle (15°–20°) segments exhibited higher differential stress of 81.4–132 MPa and shear rupture rate of 0.6–1.8 compared with the moderate-angle (30°–50°) segments. The stress vector diagram indicated that both the maximum (σ1) and minimum (σ3) principal stresses were compressive (σ1, σ3 > 0), forming exclusively compressional-shear fractures. During gold mineralization under extension condition, fluid pressure reduced the effective σ1 and σ3. In the low-angle fault segments, differential directional reactivation generated new tensional-shear fractures, which intersected pre-existing compressional-shear fractures at acute angles to form an extensive fracture network. In contrast, the moderate-angle segments exhibited preferential reactivation of pre-existing fractures, with compressional-shear fractures expanding along previous fault planes. Consequently, the low-angle segments developed optimal fluid permeability networks and ore-hosting spaces favorable for gold mineralization, whereas the moderate-angle segments show poor permeability perpendicular to the fault and primarily served as fluid migration channels rather than favorable gold deposition sites. This study provides a quantitative evaluation for the formation and evolution of fractures and their controls on favorable localization of gold orebodies in Jiaodong.

Gold,a strategic and critical mineral resource,poses substantial challenges in deep exploration.This study systematically reviews and analyzes the geochemical behavior of gold mineralization,the mechanisms of gold mineralization,and the technical systems for deep exploration.Gold concentrations in crust-mantle layers remain at low levels(10-9).Through diverse fluid mineralization processes,gold achieves enrichment over a thousand-fold to form industrial-scale ore bodies.The geological characteristics,genetic models,and spatiotemporal distribution of various mineralization types-including orogenic,Jiaodong-type,porphyry-skarn,epithermal,intrusion-related gold deposits(IRGD),Carlin-type,iron oxide copper-gold(IOCG),and volcanogenic massive sulfide(VMS)deposits-indicate extensive gold mineralization processes involving the transportation and enrichment of gold by mantle-derived fluids,magmatic hydrothermal fluids,meteoric water,and other media.A tectono-dynamic model for gold mineralization is established to show diverse deposits demonstrate genetic relationships with convergent plate margin dynamics,implying their temporal distribution has correlation with supercontinent cycles.Gold mineralization in China occurs primarily in four tectonic settings:accretionary orogenesis,cratonic destruction,continental collision,and intracontinental reactivation.Research on orogenic gold deposits has advanced beyond traditional models emphasizing purely crustal metamorphic fluids in compressional settings.Current understanding recognizes that these deposits frequently form in transextensional tectonic regimes with significant contributions from mantle-derived fluids.Gold-rich porphyry deposit is considered to be formed in the middle crust thickness.Ore-forming fluid release has evolved from a model of shallow,near-ore magma exsolution to one involving exsolution from deeper magma chambers.Concurrently,the conceptual framework for magmatic evolution has shifted from the traditional"magma chamber"paradigm toward the modern"crystal mush"model.Mineralization exhibits hierarchical structural control spanning lithospheric-scale deep faults and mantle upwelling zones down to ore-field-scale features such as fault bends,fold hinges,and intrusive contacts.These multi-scale structures collectively provide essential conduits and depositional sites for fluid focusing and gold precipitation.Based on the analysis of the mineralization system,the exploration of magma and hydrothermal channels at different scales and depths,as well as the occurrence space of ore bodies,through multi-scale and multi-depth geophysical methods is a crucial approach in gold exploration.Geophysical methods,including magnetotellurics and dense nodal array,delineate deep geological structures,while wide-field electromagnetic method,spectral induced polarization,and surface-borehole transient electromagnetic method identify ore-related anomalies.Deep-penetrating geochemistry(nanoparticle tracing)is employed to detect the vertical migration patterns of elements within concealed ore bodies.Mineral spectroscopy incorporating short-wave and thermal infrared analysis enables precise targeting of hydrothermal centers and mineralized zones.Designing tailored exploration methods based on the metallogenic factors of different gold deposits,and utilize three-dimensional modeling and artificial intelligence further support multi-source data integration and intelligent prospect analysis.The establishment of genetic models,the combination of diverse prospecting techniques,and a tripartite"knowledge-data-simulation"driven prediction approach represents a critical direction for future exploration of concealed gold deposits.

Orogenic gold deposits are predominantly controlled by shear zones with ore shoots occurring in step-over zones, however, the structural controls on fluid emplacement and related multi-field coupling processes in the step-over zones remain poorly understood. Taking the Jinshan gold deposit in the Jiangnan Orogen as an example, this study employs COMSOL Multiphysics simulation software to construct a two-dimensional mineralization model based on geological frameworks and mineralization parameters. The thermo-hydro-mechanical-chemical-transport (THMCT) coupling process in both extensional and compressional step-over zones was systematically compared. Numerical modeling revealed that the ore shoots are distributed in step-over zones, consistent with the geological observations. Both extensional and compressional step-over zones exhibit similar trends in the variations of flow velocity and fluid pressure. The auriferous fluids have higher flow velocity and pressure in the narrow upstream segments, relative to the step-over zones where the widen shear zone causes a significant drop in fluid velocity and pressure. In addition to the fluid boiling caused by pressure reduction, the abrupt drop in fluid velocity in the step-over zones may be a key to trigger efficient gold precipitation due to prolonged fluid-rock interaction. Despite the similar ore-forming mechanism in the extensional and compressional step-over zones noted above, there are higher gold concentrations in the compressional step-over zone since the compaction-induced low permeability triggered the fluid retention and prolonged fluid-rock interaction. This study demonstrates the applicability of numerical simulation for investigating fluid flow processes within shear zones and the formation of ore shoots in step-over structures, with important implications for structural controls on gold mineralization.

The magmatic processes responsible for Cenozoic porphyry deposits in Tibetan post-collisional settings remain debatable. By employing integrated whole-rock (major-trace element, SrNd isotope, and PGE) and mineral geochemical analyses of lamprophyres, mafic enclaves of distinct origins, and host porphyries from the Machangqing deposit in southeastern Tibet, this study revealed a two-stage magma mixing process underpinning the porphyry mineralization. Gabbroic enclaves within lamprophyres exhibit elevated metals and volatiles, along with mineral assemblages transitional between lamprophyre and juvenile lower-crustal products (e.g., felsic intrusions and xenoliths), denoting a hybrid mafic magma (HMM) generated during Stage I (mixing between similar to 64 % lamprophyric magma and 36 % juvenile lower crust at 39-48 km depth). Stage II mixing between HMM and porphyry magma, documented by MMEs at 28-35 km depth, triggered marked enrichment of volatiles and metals in porphyries, as evidenced by elevated Cl (0.08 to 0.25 wt%) and SO3 (0.27 to 0.49 wt%) in apatite, along with Cu contents (8.52 to 100 ppm) comparable to the HMM. Notably, the decrease in total PGE contents from lowly-mixed to highly-mixed MMEs (1.67-0.57 ppb), coupled with chalcopyrite entrapment in the latter, strongly suggests a sulfide saturation process. Controlled by sulfide saturation levels in these MMEs, ionic Cu diffusion (slight saturation) and sulfide segregation (intense saturation) are revealed to underpin metal transfer from HMM to the porphyry system via Stage II mixing. This multistage magma mixing process enables the transfer of metals and volatiles from juvenile lower crust and mantle sources, laying the foundation for efficient porphyry mineralization.

Structural and paleogeographic controls on sediment-hosted Au deposits are investigated using the giant Zhaishang Au deposit in the west Qinling orogen as an example. Two distinct types of mineralization are identified. The first is fault-controlled mineralization within Devonian Fe-rich calcareous siltstone, deposited in a platform-edge environment. The second is stratabound-replacement mineralization within Permian carbonaceous mudstone. This mudstone, which contains up to 1.46% organic carbon, was deposited in a low-energy, deep-sea environment. Geophysical sections demonstrate that the two types of Au mineralization are bounded by a WNW-ESE-trending fault called F5, which extends to a depth of at least 1 km with secondary mineralized structures converging into it. New structural mapping reveals that deposit-scale, NW-SE-trending locked-up folds and thrust faults developed under north-northeast-south-southwest compression at ca. 279 to 275 Ma according to the sericite Ar-Ar dating. In situ U-Pb dating of Au-related apatite from mineralized veinlets indicates that the WNW-to E-trending reverse faulting, stratabound replacement, and Au mineralization took place at ca. 220 Ma. The fault-controlled Au in the Devonian beds comprises polymetallic sulfides associated with decarbonation with both native gold and invisible Au within pyrite. In contrast, the stratabound-replacement Au orebodies in the Permian beds comprise pyrite and arsenopyrite hosting invisible Au associated with quartz alteration. The contrasting mineralization styles can be attributed to variations in host rocks and their mechanical competency determined by distinct paleogeographic settings and different pathways for fluid-rock interaction.

Composition and source of ore-forming fluids in Jiaodong gold deposits remain controversial. To address this issue, the mineral parageneses, in situ trace element and sulfur-iron isotope of pyrite in shallow Nanlvxinmu and deep Zhaoxian gold deposits hosted by the Jiaojia Fault were analyzed. Four hydrothermal stages were identified in both two deposits: quartz-pyrite stage (I), quartz-pyrite-native gold stage (II), quartz-pyrite-chalcopyrite-pyrrhotite-galena-sphalerite stage (III), and quartz-calcite-pyrite stage (IV). Fine-coarse and euhedral-subhedral pyrites (Py2) from the gold-bearing stage II display elevated Au (median: 0.10 ppm) and Ag (median: 0.31 ppm) concentrations in contrast to low Au (median: 0.05 ppm) in other stages. The Au-related Py2 from the Nanlvxinmu deposit has delta 34S range of 11.0-12.8 %o and delta 56Fe range of 0.30-0.71 %o, and the delta 34S and delta 56Fe values of Py2 in the Zhaoxian deposit are 11.2-12.5 %o and 0.31-0.85 %o, respectively. The deduced sulfur and iron isotope compositions of initial ore-forming fluids indicate that the ore-forming fluids were derived from the overlying sediments on the subducted slab. The trace elements and S-Fe isotopes of pyrite suggest that fluid immiscibility is the primary mechanism of gold precipitation. The similar compositions and source of ore-forming fluids at shallow and deep areas of the Jiaojia Fault indicate that the deeper area of the fault zone still has gold mineralization potential.

Urban building clustering is essential for deciphering spatial structures and functional patterns. Yet, existing methods mainly rely on local or pairwise geometric similarity measures, which fail to capture the latent nonlinear topological structure of building layouts and insufficiently handle structural inconsistencies across multi-view data, leading to compromised robustness. To address these issues, this study proposes a novel multi-view clustering model that, for the first time, integrates topological manifold modeling and cross-view diversity detection in a unified framework. This model first constructs three complementary feature views (centroid distance, outline distance, and non-spatial attributes) and models latent topological manifolds within each view. A novel diversity detection mechanism is then proposed to identify and suppress inconsistent structural information both within individual views and across different views, producing a pure graph for each view, which is then fused into a consensus graph with a clear clustering structure. Finally, an alternating iterative optimization algorithm is proposed to jointly learn topological correlation, multi-view consistency, and consensus structure within a unified framework. Extensive experiments on 15 urban communities in Wuhan and Chengdu, China, show that our model consistently outperforms 12 state-of-the-art baselines, achieving up to 32% improvement in Adjusted Rand Index (ARI) and over 20% gains in Accuracy and F-score. In particular, linear patterns achieve an average accuracy of over 90%.

Stream sediment geochemistry data has emerged as a valuable tool for identifying potential mineral deposits. However, there is a severe imbalance in the distribution of known (positive) and unknown (negative) mineralization samples in these data. To address this challenge, this study proposes a potential-enhanced positiveunlabeled bagging (PEPUB) algorithm, which takes into account the potential contribution of target mineral deposits in unsampled areas. Furthermore, the PSO algorithm is employed to optimize the model's hyperparameters and enhance its performance. To validate the proposed method, we conducted tests in the Guangxi Zhuang Autonomous Region, situated on the southwestern edge of the South China Block. The results indicate that the PEPUB-based method demonstrates superior performance in predicting potential gold deposits, with an F1 score of 0.928 and a precision rate of 90.6 %. Additionally, the obtained mineralization anomaly maps show a high level of agreement between the predicted mineralization points and the known mineralization points. This model not only facilitates the identification of potential target mineral deposits and improves exploration efficiency but also offers valuable insights into the application of semi-supervised learning in mineral exploration.

Structural controls and ore fluid compositions in the Mingshan gold deposit in the Youjiang Basin remain poorly understood. Structural geometry, mineral assemblage, sulfur isotopes, and trace elements in this deposit were studied to resolve using field structural geological surveys, time-of-flight secondary ion mass spectrometry (ToFSIMS), and in situ sulfur isotope analysis. Structural investigation indicates that the gold ore bodies hosted in the Middle Triassic turbidites are controlled by NW- to NWW-trending low-angle imbricate thrust faults formed under N-S-oriented compression, and are subsequently cut by NE-trending strike-slip faults. Three stages of gold mineralization were identified, including quartz-pyrite (stage I), pyrite-arsenopyrite-quartz (stage II), and polymetallic sulfide-calcite (stage III). The pyrite comprises framboidal pyrite (Py1) and zonal hydrothermal pyrite, including the gold-arsenic-poor porous core (Py2), the arsenic-rich bright mantle (Py3), and the gold-rich rim (Py4). In situ sulfur isotope analysis reveals delta 34S values ranging from +3.1 to +15.1 %o for Py1, -8.5 to -2.4 %o for Py2, -8.0 to -0.8 %o for Py3, and -3.1 to 0.8 %o for Py4. The hydrothermal pyrite sulfur isotope composition and an increase in delta 34S values from core to rim show that ore-forming materials originate from deep source regions but are contaminated by wall rock via fluid-rock interactions. The imbricate thrust-controlled gold ore systems not only enhance our knowledge of structural deformation characteristics and metallogenic mechanisms but also provide important clues for regional prospecting and exploration.

The multi-scale controls on the spatial distribution of orebodies and gold grades at the Chaihulanzi gold deposit remain enigmatic. The orogenic gold mineralization is hosted by graphite-bearing schists, gneisses, and diorites. Our study employed Surpac 3D modeling technology to define the spatial morphology of orebodies and applied the number-size fractal model to analyze the gold grade distribution, quantitatively characterizing the influence of ore-controlling fault systems. Our 3D model is based on geological profiles, outcrop observations and drill hole data. It reveals that the NW-SE-trending and nearly E-W-trending ore-controlling faults are compatible with a Riedel shear system. The NW-SE-trending transpressional faults controlled continuous, tabular orebodies that extend into deep en-echelon veins, whereas the nearly E-W-trending transtensional faults formed discontinuous, lens-shaped orebodies. Fractal analysis indicates that gold grades in most cross-cuts display a bifractal pattern. The orebodies controlled by transpressional faults with more intense mineralization have higher fractal dimensions (D2: 0.59-5.75; median 1.84) and thresholds (median 3.1 g/t) compared to those controlled by transtensional faults (D2: 0.75-5.25; median 1.4; threshold median 1.03 g/t). This can be explained by the dense and interconnected ore-controlling microfractures in transpressional faults associated with variable gold grade distribution, relative to sparse and dispersed microfractures in transtensional faults associated with uniform gold grade distribution. The gold grades of orebodies are decreasing in wall rocks from graphite-bearing schist to gneiss to diorite porphyry, which, together with a decreasing intensity of quartz-sericite alteration, can be attributed to the influence of fluid-rock reactions. Our study contributes to the better understanding of deposit-scale and micro-scale controls on mineralization and gold grades at the Chaihulanzi deposit with significant implications for optimizing deep and regional exploration strategies.