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[Display omitted] • Seabee Gold Operation that hosts Santoy and Fisher yield a similar ore genesis. • Fisher and Santoy deposits host multi-stage system of orogenic gold mineralization. • Early gold mineralization overprinted by main-stage orogenic mineralization. • Mineral chemistry of alteration mineral assemblages similar for Fisher and Santoy. The Seabee Gold Operation, located in northern Saskatchewan, Canada, hosts the Santoy and Seabee gold deposits, as well as the Fisher property; the latter is an important exploration target. This gold mineralization is hosted in rocks of the Pine Lake greenstone belt that is within the Glennie domain of the larger Paleoproterozoic Trans-Hudson orogen. Mineralization is focused within shear zones, including the Santoy shear system that extends south onto the Fisher property. The role of ore-adjacent intrusions, systematics of gold mineralization, and relationship between the mineralization of the properties are largely undefined. In this study, hydrothermally-altered samples from locations along the Santoy shear system, namely the Santoy 7, Santoy Gap, and the Fisher property, were analyzed to identify and compare the mineralogical and geochemical characteristics related to sulfide-gold mineralization and associated alteration. The altered host rocks primarily comprise upper greenschist to lower amphibolite-grade sheared metabasalt to chlorite-hornblende-biotite ± garnet schist, and intrusive rocks dominated by granodiorite and tonalite. These lithologies are cut by similar quartz vein generations and are associated with similar alteration assemblages and mineralization, including (i) syn -late-D 3 "distal" (∼0.4 to 3 m wide) sericite-biotite-chlorite-clinozoisite ± albite, titanite to vein-adjacent coarse-grained diopside-K-feldspar-albite-actinolite ± apatite, titanite calc-silicate alteration, associated with main-stage Py 2a, 2b -Cpy 2 -Po 1 -Au (syn -late-D 3) mineralization; (ii) remobilized, fracture-filling Py 3 -Po 2- Cpy 3 -Au-BiTel (late-D 3) mineralization within the calc-silicate assemblage; and (iii) early colloform Py 1a (pre- syn -D 3) and intrusion-hosted, inclusion-rich Py 1b (pre-D 3). Microprobe analyses reveal similar mineralogical trends between Fisher and Santoy alteration minerals typical of orogenic gold systems. Empirical geothermobarometric calculations of gold-associated vein-adjacent and vein-hosted chlorite and biotite exhibit orogenic-style formation conditions (∼320–330 °C, 3 kbar, ∼9 km depth). As such, these analyses suggest that the Fisher property and Santoy Mine Complex underwent inter-connected, multi-stage hydrothermal processes. These stages comprise (i) a potential early introduction of gold into the system closer to the timing of plutonism (Py 1b magmatic-hydrothermal; pre-D 1) or during the onset of gold mineralization (Py 1a ; orogenic; late-D 2 to early- syn -D 3) during the evolution of the Reindeer zone; (ii) orogenic main-stage mineralization (syn -late-D 3) concurrent with late- to post- collisional deformation throughout the Reindeer zone; and (iii) remobilization during continuous deformation (late-D 3) where elevated cyclical fluid fluxes and higher fracture density at Santoy produced higher-grade mineralization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fractal and multifractal analyses were used to study four orogenic gold provinces. • Case study conducted on a key deposit at the local and micro scales. • Fractal dimension maps showed good correlation with known mineral occurrences. • Orogenic gold deposits showed multifractal behavior. • Multifractal indices help obtain information on gold deposits in multiple scales. Understanding the controls on the spatial distribution of mineral deposits is crucial for prospecting new occurrences. Various geological processes operate together at microscopic to macroscopic scales, generating mineral systems responsible for significant accumulations of economic minerals. This characteristic of functioning at various scales, accompanied by repetition of features over space during mineralization, indicates that these processes are self-similar, meaning they exhibit fractal geometry. Previous research has demonstrated that the combined action of processes involved in mineralization in such critical, nonlinear systems, produces objects with multifractal characteristics. Therefore, the spatial distribution of mineral deposits should be studied using appropriate methods for better understanding of their controls. In this context, this study investigated the multiscale geometric characteristics of worldclass orogenic gold systems in Archean greenstone belts using fractal and multifractal analyses. First, at the macroscopic-scale, regional-scale features were considered in the major greenstone belt provinces with orogenic gold deposits worldwide, namely: Abitibi (Canada), Norseman–Wiluna (Australia), Rio das Velhas (Brazil), and Central Lapland (Finland). Next, at an intermediate scale, local-scale features were examined in detail within the context of the Córrego do Sítio Lineament. Finally, at the microscopic scale, the focus was on the Córrego do Sítio orogenic gold deposit—a key deposit in the Rio das Velhas greenstone belt. Fractal dimensions of the spatial distributions of mineral deposits, magnetic lineaments, and their intersections were investigated at the macroscopic to local scales, as well as the spatial distribution of ore minerals at the microscopic scale, using the box-counting method. Maps of fractal dimensions of magnetic lineaments were generated and compared with the spatial distribution and tonnage of orogenic gold deposits at the regional scale. The same features were analyzed using the method of multifractal moments. The results at the three scales were analyzed and synthesized to identify meaningful patterns for understanding these orogenic gold systems. With regard to fractality, the orogenic gold deposits in all the investigated provinces exhibited unique spatial distributions at different scales, namely: less than 2–4 km, from 2 to 4 km to 10–30 km, and more than 10–30 km. The analysis of magnetic lineaments yielded a correlation between gradients of fractal dimensions and gold tonnages in the orogenic gold deposits. The multifractal analyses indicate multifractal geometries extending from the microscopic to the macroscopic scale. The calculated multifractal indices of Δα (singularity variation), τ"(1) (multifractality index), and Δf(α) (multifractal spectrum variation) showed direct relationships with endowment of orogenic gold in the studied provinces, as well as with differences in mineralization styles in thin sections. The findings demonstrate the effectiveness of the analyses used for improved characterization of the studied mineral systems; they also allow comparing similar systems at different scales and locations and they can be used to study other mineral systems with similar geological controls. [ABSTRACT FROM AUTHOR]