Constraints on the genesis of Au veins in interior Alaska: Evidence from geochronology and vein textures

Douglas C. Kreiner; William Thompson; Jonathan Saul Caine; Ashleigh Ball; Christopher S. Holm-Denoma; Paul O’Sullivan; Holly J. Stein

USGS · 70248459

Constraints on the genesis of Au veins in interior Alaska: Evidence from geochronology and vein textures

Douglas C. Kreiner·William Thompson·Jonathan Saul Caine·Ashleigh Ball·Christopher S. Holm-Denoma·Paul O’Sullivan·Holly J. Stein

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Abstract

The origin of Au-bearing, low sulfide quartz veins in the Pogo and Tibbs Creek regions of interior Alaska remain enigmatic. Intrusion-related Au and mesozonal orogenic vein models have both been proposed (Thompson and Newberry, 2000; Rhys et al., 2003; Goldfarb et al., 2022; Dilworth et al., 2007). To date, studies of igneous geochronology and metamorphic timing have shown that gold veins formed between intervals of magmatism and post-date regional metamorphic fabrics. Relatively little description of detailed mineralogy, vein textures, and absolute timing of mineralization exist – resulting in new questions about the deposit origin. This study attempts to relate these parameters through investigation of new U-Pb crystallization and Re-Os mineralization ages combined with detailed descriptions of vein textures to constrain the origin of the veins.

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Source-reported bounding extent: 61.56694937120494° to 65.5506094851404° latitude; -149.72901973722165° to -139.05576620713518° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Douglas C. Kreiner, William Thompson, Jonathan Saul Caine, Ashleigh Ball, Christopher S. Holm-Denoma, Paul O’Sullivan, Holly J. Stein. 2023. Constraints on the genesis of Au veins in interior Alaska: Evidence from geochronology and vein textures. https://pubs.usgs.gov/publication/70248459

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