Ella Curtis, BSc

E. Curtis¹, O.A¹, D.G^1 
1Department of Earth Science, University of Toronto, Toronto, ON, Canada 

Young-Davidsons (YD) mine at Matachewan offers an interesting opportunity to explore how we utilize technology around alteration haloes and better our understanding of orogenic gold deposits. Situated in Northern Ontario YD is located in the southwest of the Abitibi greenstone belt, part of the Superior province. More specifically, the site is located on the western limb of the Larder Lake Cadillac deformation zone (LLCdz) and hosts a series of deformation and vein formation events. On-site gold mineralization is primarily hosted in a large syenite intrusion with an extensive hydrothermal alteration halo. The primary target for gold production is quartz veins with a strong hematite alteration. This study focuses on the use of shortwave infrared (SWIR) analyses to identify major alteration minerals and thus enhance the understanding of the deposit, particularly the distinctive features of the alteration halo. SWIR identifies the composition of a sample by recording the wavelengths reflected off the samples. Due to its structure, each mineral will return a different combination of wavelength and intensity that can be compared to a stored mineral library. The use of SWIR improves the efficiency and accuracy of identifying alteration haloes made during in-core logging. We also present a comparison of SWIR and results from whole-rock geochemical analysis to create a comprehensive model of alteration halos around the YD orogenic gold deposits. Through the use of this technology this study will enhance understanding of site geology as well as build on techniques to identify alteration halos of orogenic gold deposits.