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Authordc.contributor.authorReich Morales, Martín 
Authordc.contributor.authorParada Reyes, Miguel es_CL
Authordc.contributor.authorPalacios Monasterio, Carlos es_CL
Authordc.contributor.authorDietrich, Andreas es_CL
Authordc.contributor.authorSchultz, Frank es_CL
Authordc.contributor.authorLehmann, Bernd es_CL
Admission datedc.date.accessioned2007-06-04T21:12:36Z
Available datedc.date.available2007-06-04T21:12:36Z
Publication datedc.date.issued2003-10
Cita de ítemdc.identifier.citationMINERALIUM DEPOSITA 38 (7): 876-885 OCT 2003en
Identifierdc.identifier.issn0026-4598
Identifierdc.identifier.urihttp://repositorio.uchile.cl/handle/2250/124649
Abstractdc.description.abstractAdakite-like features are recognized in the Late Miocene (similar to10 Ma) porphyritic intrusions of the Los Pelambres giant porphyry copper deposit, central Chile (32degreesS). Located within the southern portion of the flat-slab segment (28-33degreesS) of the Chilean Andes, the Al- and Na-rich porphyries of Los Pelambres display distinctly higher Sr/Y (similar to100-300) and La-N/Yb-N (similar to25-60) ratios than contemporaneous and barren magmatic units (e.g., La Gloria pluton, Cerro Aconcagua volcanic rocks) of the same Andean magmatic belt. Strong fractionation of heavy rare earth elements (HREE), absence of Eu anomalies, high Sr/Y and Zr/Sm and low Nb/Ta ratios suggest melt extraction from a garnet-amphibolite source. The Late-Miocene adakite-like porphyritic intrusions at Los Pelambres formed closely related in time and space to the subduction of the Juan Fernaandez Ridge (JFR) hotspot chain along the Chilean margin. Current tectonic reconstructions reveal that, at the time of formation of the Los Pelambres rocks, a W-E segment of the JFR started to subduct beneath them, producing a slow-down of a previously rapid southward migration of a NE-ridge-trench collision. These particular tectonic conditions are favorable for the origin of the Los Pelambres porphyry suite by melting of subducting young hotspot rocks under flat-slab conditions. The incorporation of crustal components into the oceanic lithopheric magma source by subduction erosion is evidenced by the Sr-Nd isotope composition of the Los Pelambres rocks different from the MORB signatures of true adakites. A close relationship apparently exists between the origin of this adakite-like magmatism and the source of the mineralization in the Los Pelambres porphyry copper deposit.en
Lenguagedc.language.isoenen
Publisherdc.publisherSPRINGER-VERLAGen
Keywordsdc.subjectCALC-ALKALINE MAGMATISMen
Títulodc.titleAdakite-like signature of Late Miocene intrusions at the Los Pelambres giant porphyry copper deposit in the Andes of central Chile: metallogenic implicationsen
Document typedc.typeArtículo de revistaen


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