Integrated portable and micro-XRF analysis of alteration and mineral systems in southwestern New Brunswick: Implications for regional exploration

Southern New Brunswick's protracted and complex tectonic history has resulted in a diverse spectrum of mineral deposit types. In this study, numerous samples were collected from both outcrops and drill core to evaluate the mineralization styles and mineral potential of the region. Geochemical characterization of these samples was obtained using an Olympus Vanta™ portable X-ray fluorescence (pXRF) analyzer, followed by a rigorous QA/QC procedure to ensure analytical precision and accuracy. In addition, multi-elemental μ-XRF mapping of polished thick sections was performed to document elemental distribution and mineralization textures at the microscale. Principal Component Analysis (PCA) on centered log-ratio (CLR)–transformed data was used to investigate inter-element relationships and delineate alteration and mineralization trends across the study area. Hydrothermal alteration was further assessed through geochemical indices, including the Ishikawa Alteration Index (AI), the Chlorite–Carbonate–Pyrite Index (CCPI), and (2Ca + Na + K)/Al versus K/Al molar ratio diagrams. Results from the PCA, petrological observations, and alteration indices collectively indicate that the dominant alteration assemblages in the region are propylitic–chloritic–sericitic ± carbonatization. Multiple mineral systems were recognized, including orogenic gold, intrusion-related gold, epithermal, and iron-oxide–copper–gold –style mineralization, as well as several multi-phase systems characterized by overprinting of successive veining and sulphide precipitation events, predominantly associated with quartz‑carbonate vein networks. These results highlight the high mineral potential of southwestern New Brunswick and emphasizes the need for further detailed exploration activities to refine the timing and genetic relationships among these mineral systems and assess their economic significance.