No abstract

This is an Accepted Manuscript for the Microscopy and Microanalysis 2020 Proceedings. This version may be subject to change during the production process.

The Monument Bay project is an Archean Greenstone-hosted gold deposit located ~570 km NW of Winnipeg, MB. The project is located within the Stull Lake Greenstone Belt, situated in the NW part of the Superior Province. Significant gold grades revealed in previous studies suggest that there is strong potential for the exploitation of gold reserves at the deposit [1]. The project area comprises three main rock groups (metavolcanic, felsic intrusive, and metasedimentary rocks) and six different prospecting target zones: Twin Lakes, Twin Lakes West, AZ, South Limb Shear, Mideast, and the Fence. Each target encompasses at least three different styles of hydrothermal alteration including carbonate, sericite, and chlorite alteration. The objective of this project is to delineate the mineralogical and geochemical footprint of the deposit by identifying and characterizing these alteration styles and their relationship to gold mineralization. It is important to understand the relationships between the targets to effectively vector towards future discoveries in underexplored regions of the property. Additionally, in developing a comprehensive understanding of the broad alteration footprint, the subsequent detection of gold mineralized zones can be applied on a district-wide scale. Chemical and mineralogical characteristics of the alteration footprint may help determine the proximity to high-grade Au mineralized zones. A combination of optical petrography, synchrotron radiation X-ray fluorescence (SR-XRF), and synchrotron radiation X-ray diffraction (SR-XRD) is being used to characterize in detail the chemical and mineralogical alteration footprint of the Monument Bay deposit.

The growth history of pyrite can preserve changes in auriferous fluid chemistry in its distribution of trace elements across a wide range of temperature conditions. Moreover, sulfide geochemistry can be used as an effective proxy for fluid history as information recorded by different fluid events can be inferred through observation of different generations of pyrite growth [2]. In addition, quantitative Au/Ag ratios can provide complementary information about the composition of gold grains. Understanding associations of other trace elements with gold in sulfides and the composition of gold grains can aid in differentiating mineralizing events with implications for improving exploration and geometallurgy at the Monument Bay deposit.

This is an Accepted Manuscript for the Microscopy and Microanalysis 2020 Proceedings. This version may be subject to change during the production process.