Re-Os isotope systematics of sulfides from felsic igneous rocks: Application to base metal porphyry mineralization in Chileстатья из журнала
Аннотация: Research Article| September 01, 1997 Re-Os isotope systematics of sulfides from felsic igneous rocks: Application to base metal porphyry mineralization in Chile Claire Freydier; Claire Freydier 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Search for other works by this author on: GSW Google Scholar Joaquin Ruiz; Joaquin Ruiz 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Search for other works by this author on: GSW Google Scholar John Chesley; John Chesley 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Search for other works by this author on: GSW Google Scholar Tom McCandless; Tom McCandless 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Search for other works by this author on: GSW Google Scholar Francisco Munizaga Francisco Munizaga 2Departamento de Geologia, Universidad de Chile, Santiago, Chile Search for other works by this author on: GSW Google Scholar Author and Article Information Claire Freydier 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Joaquin Ruiz 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 John Chesley 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Tom McCandless 1Department of Geosciences, University of Arizona, Tucson, Arizona 85721 Francisco Munizaga 2Departamento de Geologia, Universidad de Chile, Santiago, Chile Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1997) 25 (9): 775–778. https://doi.org/10.1130/0091-7613(1997)025<0775:ROISOS>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Claire Freydier, Joaquin Ruiz, John Chesley, Tom McCandless, Francisco Munizaga; Re-Os isotope systematics of sulfides from felsic igneous rocks: Application to base metal porphyry mineralization in Chile. Geology 1997;; 25 (9): 775–778. doi: https://doi.org/10.1130/0091-7613(1997)025<0775:ROISOS>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Dating sulfides and determining the source of ore-forming metals have been limiting factors in our understanding of processes that produce hydrothermal ore deposits. Here we analyze sulfides from base metal porphyry deposits from Chile to demonstrate the potential of the Re-Os system to determine both the age and the source of metals for hydrothermal mineralization. Cogenetic chalcopyrite, bornite, pyrite, and sphalerite from El Teniente (ca. 5 Ma) have 187Re/188Os ratios from 0.3 to 21.8 and initial 187Os/188Os ratios from 0.17 to 0.22. A paragenetically late pyrite that has an initial 187Os/188Os of 0.88 indicates that the ore deposit is not isotopically homogeneous in Os throughout the formation of the deposit. Pyrite samples from Andacollo (ca. 100 Ma) have 187Re/188Os ratios from 15 to 3600, and different isochrons yield ages between 87 and 103 Ma, consistent with different sericite K-Ar ages. Initial 187Os/188Os ratios of 0.2 to 1.1 are similar to those of El Teniente. The relatively homogeneous 187Os/188Os ratios (∼ 0.19) for cogenetic sulfides from El Teniente suggest that most of the Os in the ore was from the causal intrusive. The late-stage pyrite probably incorporated Os leached from the country rock by meteoric fluids, which mixed with magmatic fluids at the periphery of the hydrothermal system. We demonstrate that the Re-Os isotope system can be a powerful geochronological tool in hydrothermal ore deposits. The large range in Re/Os ratios of sulfides permits the age of mineralization to be well constrained, despite isotopic heterogeneities of the hydrothermal fluids. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Год издания: 1997
Издательство: Geological Society of America
Источник: Geology
Ключевые слова: Geological and Geochemical Analysis, Geochemistry and Geologic Mapping, earthquake and tectonic studies
Открытый доступ: closed
Том: 25
Выпуск: 9
Страницы: 775–775