Garnet lherzolite and garnet-spinel mylonite in the Ronda peridotite: Vestiges of Oligocene backarc mantle lithospheric extension in the western Mediterranean
2011; Geological Society of America; Volume: 39; Issue: 10 Linguagem: Inglês
10.1130/g31760.1
ISSN1943-2682
AutoresCarlos J. Garrido, Frédéric Gueydan, Guillermo Booth‐Rea, Jacques Précigout, Károly Hidas, José Alberto Padrón‐Navarta, Claudio Marchesi,
Tópico(s)Geological and Geochemical Analysis
ResumoResearch Article| October 01, 2011 Garnet lherzolite and garnet-spinel mylonite in the Ronda peridotite: Vestiges of Oligocene backarc mantle lithospheric extension in the western Mediterranean Carlos J. Garrido; Carlos J. Garrido * 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain *E-mail: carlos.garrido@csic.es. Search for other works by this author on: GSW Google Scholar Frédéric Gueydan; Frédéric Gueydan 2Géosciences Rennes, Université Rennes 1, Campus de Beaulieu, 35042 Rennes, France Search for other works by this author on: GSW Google Scholar Guillermo Booth-Rea; Guillermo Booth-Rea 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain3Departamento Geodinámica Interna, Universidad de Granada, Facultad de Ciencias, 18002 Granada, Spain Search for other works by this author on: GSW Google Scholar Jacques Precigout; Jacques Precigout 4Geologisches Institute, ETH-Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Karoly Hidas; Karoly Hidas 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain Search for other works by this author on: GSW Google Scholar José A. Padrón-Navarta; José A. Padrón-Navarta 5Departamento Mineralogía y Petrología, Facultad de Ciencias, Universidad de Granada, 18002 Granada, Spain Search for other works by this author on: GSW Google Scholar Claudio Marchesi Claudio Marchesi 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain Search for other works by this author on: GSW Google Scholar Author and Article Information Carlos J. Garrido * 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain Frédéric Gueydan 2Géosciences Rennes, Université Rennes 1, Campus de Beaulieu, 35042 Rennes, France Guillermo Booth-Rea 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain3Departamento Geodinámica Interna, Universidad de Granada, Facultad de Ciencias, 18002 Granada, Spain Jacques Precigout 4Geologisches Institute, ETH-Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Karoly Hidas 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain José A. Padrón-Navarta 5Departamento Mineralogía y Petrología, Facultad de Ciencias, Universidad de Granada, 18002 Granada, Spain Claudio Marchesi 1Instituto Andaluz de Ciencias de la Tierra (IACT), CSIC and UGR, Avenida de las Palmeras 4, 18100 Armilla, Granada, Spain *E-mail: carlos.garrido@csic.es. Publisher: Geological Society of America Received: 16 Sep 2010 Revision Received: 26 Apr 2011 Accepted: 30 Apr 2011 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (10): 927–930. https://doi.org/10.1130/G31760.1 Article history Received: 16 Sep 2010 Revision Received: 26 Apr 2011 Accepted: 30 Apr 2011 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Carlos J. Garrido, Frédéric Gueydan, Guillermo Booth-Rea, Jacques Precigout, Karoly Hidas, José A. Padrón-Navarta, Claudio Marchesi; Garnet lherzolite and garnet-spinel mylonite in the Ronda peridotite: Vestiges of Oligocene backarc mantle lithospheric extension in the western Mediterranean. Geology 2011;; 39 (10): 927–930. doi: https://doi.org/10.1130/G31760.1 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 Uplift and exhumation of vast exposures of diamond facies, subcontinental mantle peridotite in the Western Mediterranean arc are attributed to tectonic scenarios including pure extension, transpression or subduction followed by delamination-driven or rollback-driven stretching. In the Ronda peridotite (southern Spain) the strong overprint of low-pressure assemblages has precluded accurate determination of the pressure and temperature conditions for the onset of exhumation that formed the spinel tectonite and garnet-spinel mylonite domain in this massif. Here we report unequivocal petrographic evidence for the existence of prekinematic, coarse-grained garnet lherzolite assemblages from the garnet-spinel mylonite domain of the Ronda peridotite. Application of well-calibrated geothermobarometers yields prekinematic minimum equilibration conditions of 2.4–2.7 GPa and 1020–1100 °C, demonstrating that the Ronda peridotite equilibrated at ∼85 km depth before shearing. We also show the existence of synkinematic garnet and spinel assemblages that overprinted garnet lherzolite assemblages at 800–900 °C and 1.95–2.00 GPa. The decompressional cooling path and high pressure recorded by garnet-spinel mylonites rule out their formation by near-isobaric cooling above a subduction-collision wedge or during or after the emplacement of the peridotite massif into the crust. Ronda garnet-spinel mylonites represent the vestiges of subcontinental mantle ductile shear zones formed at early stages of lithosphere extension during backarc extension in the western Mediterranean. Southward to westward retreat of the African slab during the Oligocene-Early Miocene accounts for intense backarc lithosphere extension and development of the Ronda extensional shear zone, coeval with extreme thinning of the Alborán domain overlying crust. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
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