Intrusion-related mineralization in the central sector of the Sierra Madre Oriental, Mexico

Persistent Link:
http://hdl.handle.net/10150/280679
Title:
Intrusion-related mineralization in the central sector of the Sierra Madre Oriental, Mexico
Author:
Castro-Reino, Sergio Francisco
Issue Date:
2004
Publisher:
The University of Arizona.
Rights:
Copyright © 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.
Abstract:
The Concepcion del Oro, Providencia, Noche Buena and Santa Rosa igneous centers are located in the central sector of the Sierra Madre Oriental, to the southwest from the city of Saltillo, in the state of Zacatecas, Mexico. Their associated mineral deposits constitute a coherent igneous and metallogenic area. It is characterized by a sequence of magmatic bodies intruding a predominantly carbonate sedimentary sequence of Mesozoic age. Field reconnaissance, whole rock major, trace and isotope geochemistry, and mineral chemistry define three magmatic pulses. The first pulse is characterized by a intermediate to mafic, relatively oxidized magma with low contents in halogens that becomes more contaminated with crustal material, enriched in fluorine relative to chlorine, and reduced as it evolves. The second pulse is at first more oxidized than the previous, but, like its later phases, it shows also significant crustal contamination and relatively high halogen contents. It becomes significantly more reduced, its overall halogen contents decreases and becomes strongly dominated by fluorine towards the late stages. A late magmatic pulse consisting of mafic dikes with major and trace element characteristics suggestive of a crustal, rather than mantle source, does not appear to be related to significant alteration and mineralization in the area. Trace element and radiogenic isotope geochemical data suggest similar sources for the different intrusive phases in the area with a significant component from either a mafic crust and/or the mantle. Amphibole geobarometry suggests final emplacement of the different intrusives at less than or around 1 kbar pressure, in agreement with the regionalGeology. Values obtained from relict inclusions, show a cluster of values between 3 and 4 kbars that suggest possible mid-crustal residence for the magmas in the area. Halogen contents and oxidation state of the different intrusives appear to describe similar evolutionary trends. Available field evidence, geochemical data and documented metal suites associated with the intrusives, indicate that mineralization is dominated by copper in the early phases, and lead-zinc-silver in the later. While the lead-zinc-silver mineralization has many parallels to other mineralized systems in the Sierra Madre Oriental, the significant copper mineralization is uncommon for the region.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Geology.; Mineralogy.; Geochemistry.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Geosciences
Degree Grantor:
University of Arizona
Advisor:
Barton, Mark D.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleIntrusion-related mineralization in the central sector of the Sierra Madre Oriental, Mexicoen_US
dc.creatorCastro-Reino, Sergio Franciscoen_US
dc.contributor.authorCastro-Reino, Sergio Franciscoen_US
dc.date.issued2004en_US
dc.publisherThe University of Arizona.en_US
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_US
dc.description.abstractThe Concepcion del Oro, Providencia, Noche Buena and Santa Rosa igneous centers are located in the central sector of the Sierra Madre Oriental, to the southwest from the city of Saltillo, in the state of Zacatecas, Mexico. Their associated mineral deposits constitute a coherent igneous and metallogenic area. It is characterized by a sequence of magmatic bodies intruding a predominantly carbonate sedimentary sequence of Mesozoic age. Field reconnaissance, whole rock major, trace and isotope geochemistry, and mineral chemistry define three magmatic pulses. The first pulse is characterized by a intermediate to mafic, relatively oxidized magma with low contents in halogens that becomes more contaminated with crustal material, enriched in fluorine relative to chlorine, and reduced as it evolves. The second pulse is at first more oxidized than the previous, but, like its later phases, it shows also significant crustal contamination and relatively high halogen contents. It becomes significantly more reduced, its overall halogen contents decreases and becomes strongly dominated by fluorine towards the late stages. A late magmatic pulse consisting of mafic dikes with major and trace element characteristics suggestive of a crustal, rather than mantle source, does not appear to be related to significant alteration and mineralization in the area. Trace element and radiogenic isotope geochemical data suggest similar sources for the different intrusive phases in the area with a significant component from either a mafic crust and/or the mantle. Amphibole geobarometry suggests final emplacement of the different intrusives at less than or around 1 kbar pressure, in agreement with the regionalGeology. Values obtained from relict inclusions, show a cluster of values between 3 and 4 kbars that suggest possible mid-crustal residence for the magmas in the area. Halogen contents and oxidation state of the different intrusives appear to describe similar evolutionary trends. Available field evidence, geochemical data and documented metal suites associated with the intrusives, indicate that mineralization is dominated by copper in the early phases, and lead-zinc-silver in the later. While the lead-zinc-silver mineralization has many parallels to other mineralized systems in the Sierra Madre Oriental, the significant copper mineralization is uncommon for the region.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectGeology.en_US
dc.subjectMineralogy.en_US
dc.subjectGeochemistry.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineGeosciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorBarton, Mark D.en_US
dc.identifier.proquest3158075en_US
dc.identifier.bibrecord.b47906856en_US
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