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Geochronology and geology of late Oligocene through Miocene volcanism and mineralization in the western San Juan Mountains, Colorado

Dana J. Bove·Ken Hon·Karin E. Budding·John F. Slack·Lawrence W. Snee·Ross A. Yeoman
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Abstract

This paper presents 25 new 40Ar/39Ar dates from the main calc-alkaline ash-flow sheets and related younger plutons of the western San Juan volcanic field, the ash-flow sheets of the Lake City caldera cycle, and veins and other altered rocks in the Lake City region. The goal of the study was to produce similar quality 40Ar/39Ar ages to those currently published for the eastern and central San Juan Mountains. These new data provide a much more precise chronological framework for interpreting durations of events and their relationship to mineralization than do previously published conventional K-Ar dates for the western San Juan Mountains.

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Dana J. Bove, Ken Hon, Karin E. Budding, John F. Slack, Lawrence W. Snee, Ross A. Yeoman. 2001. Geochronology and geology of late Oligocene through Miocene volcanism and mineralization in the western San Juan Mountains, Colorado. https://doi.org/10.3133/pp1642

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