Petrogenesis of the phase 1 gabbro-diorite of the Miocene Mt Perkins Pluton, northwest Arizona: Implications for the role of mantle-derived mafic magmas in calc-alkaline magma evolution
type: CreativeWork
description: Mafic magmas play a significant role in the evolution of calc-alkaline magma systems in convergent and extensional environments. The Miocene Mt. Perkins pluton, northwestern Arizona, was emplaced as a series of four discrete magma pulses into a country rock of Precambrian orthogneiss. Phase 1 is a gabbro-diorite containing four rock groups: olivine-clinopyroxene cumulates, hornblende-plagioclase cumulates, homblende gabbro, and quartz diorite. Stage one of phases 2 and 3 evolved by a process of fractional crystallization of an asthenospheric mantle derived mafic magma and magma mixing with an upper crustal granitic magma. Phase 1 magmas evolved by fractional crystallization (required by the presence of cumulates) of an asthenospheric mantle derived mafic magma and contamination by an asthenospheric-lithospheric mantle derived basaltic magma at depth and the orthogneiss at emplacement level. Phases 1, 2, and 3 share a common asthenospheric mantle derived magma. Mafic mantle derived melts are generated continuously throughout magma system evolution.
abstract: Mafic magmas play a significant role in the evolution of calc-alkaline magma systems in convergent and extensional environments. The Miocene Mt. Perkins pluton, northwestern Arizona, was emplaced as a series of four discrete magma pulses into a country rock of Precambrian orthogneiss. Phase 1 is a gabbro-diorite containing four rock groups: olivine-clinopyroxene cumulates, hornblende-plagioclase cumulates, homblende gabbro, and quartz diorite. Stage one of phases 2 and 3 evolved by a process of fractional crystallization of an asthenospheric mantle derived mafic magma and magma mixing with an upper crustal granitic magma. Phase 1 magmas evolved by fractional crystallization (required by the presence of cumulates) of an asthenospheric mantle derived mafic magma and contamination by an asthenospheric-lithospheric mantle derived basaltic magma at depth and the orthogneiss at emplacement level. Phases 1, 2, and 3 share a common asthenospheric mantle derived magma. Mafic mantle derived melts are generated continuously throughout magma system evolution.
author: Danielson, Lisa Renee
date published: 1998-01-01T08:00:00Z
date modified: 2026-07-24T05:24:53Z
provider: University of Nevada - Las Vegas
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Nevada, Las Vegas

PropertyValue
property ID: DOI
value: 10.25669/xwjo-46te