Geology, geochronology, geochemistry, and Pb-isotopic compositions of Proterozoic rocks, Poachie region, west-central Arizona — A study of the east boundary of the Proterozoic Mojave crustal province

Bruce Bryant; J. L. Wooden; L. David Nealey

doi:10.3133/pp1639

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Geology, geochronology, geochemistry, and Pb-isotopic compositions of Proterozoic rocks, Poachie region, west-central Arizona — A study of the east boundary of the Proterozoic Mojave crustal province

Bruce Bryant·J. L. Wooden·L. David Nealey

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Abstract

The Poachie region at the south edge of the Colorado Plateau transition zone in western Arizona is underlain by early and middle Proterozoic plutonic rocks locally separated by screens of amphibolite-facies early Proterozoic metamorphic rocks and is in the eastern part of the Mojave crustal province, as shown by 35 Pb-isotope analyses of rocks and feldspars. Previously published mapping, 10 U-Pb zircon ages, 55 rock analyses, and other studies in the larger region of the transition zone lead to interpretation of the history and origin of the Proterozoic crust.

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Source-reported bounding extent: 34.255° to 34.576° latitude; -113.638° to -112.969° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Bruce Bryant, J. L. Wooden, L. David Nealey. 2001. Geology, geochronology, geochemistry, and Pb-isotopic compositions of Proterozoic rocks, Poachie region, west-central Arizona — A study of the east boundary of the Proterozoic Mojave crustal province. https://doi.org/10.3133/pp1639

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