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dc.contributor.authorHarris, Jonathan O.
dc.creatorHarris, Jonathan O.en
dc.date.accessioned2015-06-18T11:11:04Zen
dc.date.available2015-06-18T11:11:04Zen
dc.date.issued1984en
dc.identifier.urihttp://hdl.handle.net/10150/557993en
dc.description.abstractThe Cornelia Pluton was previously found to have been faulted in two (Gilluly, 1946). The downthrown apex is host to a copper ore-body, and the upthrown block represents a vertical cross-section of the igneous system. Field work confirmed the character of the relationship between three texturally-distinct quartz monzonites described by Wadsworth (1968). Plagioclase crystals were chosen from all the phases, including previously undescribed hydrothermal rocks, and analyzed with a microprobe. Graphs of anorthite content versus radial distance revealed systematic patterns of compositional variation, analysis of which yielded a consistent, time-dependent model for the emplacement and crystallization of the system. The granodiorite resulted from an earlier intrusive event. The quartz monzonites crystallized initially downward from the system's roof, and, subsequently, upward from the floor. Saturation of the remaining pocket(s) of magma led to the development of an inner fine-grained phase, and possibly, the evolution of hydrothermal fluids. The genetic connection between these fluids and eventual mineralization of the cupola is suggested.
dc.language.isoen_USen
dc.publisherThe University of Arizona.en
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en
dc.subjectGeology -- Arizona -- Ajo Region.en
dc.subjectGeology -- Arizona -- Pima County.en
dc.subjectIntrusions (Geology) -- Arizona -- Ajo Region.en
dc.subjectIntrusions (Geology) -- Arizona -- Pima County.en
dc.subjectPlagioclase.en
dc.titleThe emplacement and crystallization of the cornelia pluton, Ajo, Arizona: an analysis based on the compositional zoning of plagioclase and field relationsen
dc.typetexten
dc.typeThesis-Reproduction (electronic)en
dc.identifier.oclc12264509en
dc.identifier.oclc12264463en
thesis.degree.grantorUniversity of Arizonaen
thesis.degree.levelmastersen
thesis.degree.disciplineGeosciencesen
thesis.degree.disciplineGraduate Collegeen
thesis.degree.nameM.S.en
dc.description.noteThis item was digitized from a paper original and/or a microfilm copy. If you need higher-resolution images for any content in this item, please contact us at repository@u.library.arizona.edu.en
dc.identifier.bibrecord.b15155778en
dc.identifier.bibrecord.b15155754en
dc.identifier.callnumberE9791 1984 160en
refterms.dateFOA2018-06-14T16:40:42Z
html.description.abstractThe Cornelia Pluton was previously found to have been faulted in two (Gilluly, 1946). The downthrown apex is host to a copper ore-body, and the upthrown block represents a vertical cross-section of the igneous system. Field work confirmed the character of the relationship between three texturally-distinct quartz monzonites described by Wadsworth (1968). Plagioclase crystals were chosen from all the phases, including previously undescribed hydrothermal rocks, and analyzed with a microprobe. Graphs of anorthite content versus radial distance revealed systematic patterns of compositional variation, analysis of which yielded a consistent, time-dependent model for the emplacement and crystallization of the system. The granodiorite resulted from an earlier intrusive event. The quartz monzonites crystallized initially downward from the system's roof, and, subsequently, upward from the floor. Saturation of the remaining pocket(s) of magma led to the development of an inner fine-grained phase, and possibly, the evolution of hydrothermal fluids. The genetic connection between these fluids and eventual mineralization of the cupola is suggested.


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