113-12 Mineralogic and Petrologic Analysis of a Cu-W-Au-Ag Deposit in the Ferris Mountains, Wyoming

Session: Mineralogical Characterization of Economic Resources: From Critical Minerals to Gemstones (Posters)

Presenting Author:

Authors:

Abstract:

Global demand for copper is projected to increase in the coming decades, forcing geologists to assess the feasibility of previously mined and abandoned ore bodies as exploitable resources. The Ferris Mountains, located in south-central Wyoming, are predominantly porphyritic granite crosscut by mafic and pegmatitic dikes. These mountains host a Cu-W-Au-Ag deposit that was briefly mined in the 1930s but has since seen little exploration and remains poorly understood. This study aims to better understand the deposit based on mineralogic and petrologic evidence. In this study, we collected samples from outcrops and mine tailings in order to identify mineral assemblages, quantify modal abundances, and reconstruct the paragenetic sequence of mineralization. Thin section analysis was used to assess deformation, hydrothermal alteration, and host rock lithology. Mineralogical, textural, and geologic context will be used to constrain the deposit type by comparison with previously established ore deposit models. Characterizing the mineralization will provide insight into the deposit’s geologic history, alteration process, and potential economic viability. Given copper and tungsten’s critical economic role, the Ferris Mountains represent an understudied copper-tungsten resource.

Geological Society of America Abstracts with Program. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-8905

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