Dynamic growth of garnet in granitic magmas

Research Article| February 01, 2012 Dynamic growth of garnet in granitic magmas Jade Star Lackey; Jade Star Lackey * 1Geology Department, Pomona College, Claremont, California 91711, USA *E-Mail: Jadestar.Lackey@pomona.edu. Search for other works by this author on: GSW Google Scholar Gabriel A. Romero; Gabriel A. Romero 1Geology Department, Pomona College, Claremont, California 91711, USA Search for other works by this author on: GSW Google Scholar Anne-Sophie Bouvier; Anne-Sophie Bouvier † 2WiscSIMS, Department of Geoscience, University of Wisconsin, Madison, Wisconsin 53706, USA †Current Address: Institut De Minéralogie Et Géochimie, Unil-Dorigny, 1015 Lausanne, Switzerland. Search for other works by this author on: GSW Google Scholar John W. Valley John W. Valley 2WiscSIMS, Department of Geoscience, University of Wisconsin, Madison, Wisconsin 53706, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Jade Star Lackey * 1Geology Department, Pomona College, Claremont, California 91711, USA Gabriel A. Romero 1Geology Department, Pomona College, Claremont, California 91711, USA Anne-Sophie Bouvier † 2WiscSIMS, Department of Geoscience, University of Wisconsin, Madison, Wisconsin 53706, USA John W. Valley 2WiscSIMS, Department of Geoscience, University of Wisconsin, Madison, Wisconsin 53706, USA *E-Mail: Jadestar.Lackey@pomona.edu. †Current Address: Institut De Minéralogie Et Géochimie, Unil-Dorigny, 1015 Lausanne, Switzerland. Publisher: Geological Society of America Received: 12 Apr 2011 Revision Received: 19 Sep 2011 Accepted: 22 Sep 2011 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2012 Geological Society of America Geology (2012) 40 (2): 171–174. https://doi.org/10.1130/G32349.1 Article history Received: 12 Apr 2011 Revision Received: 19 Sep 2011 Accepted: 22 Sep 2011 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Jade Star Lackey, Gabriel A. Romero, Anne-Sophie Bouvier, John W. Valley; Dynamic growth of garnet in granitic magmas. Geology 2012;; 40 (2): 171–174. doi: https://doi.org/10.1130/G32349.1 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 In order to improve understanding of how accessory garnet crystallizes in igneous rocks, and evaluate it as a mineral recorder of magma history, we analyzed δ18O of garnets from the Hallowell and Togus plutons in south-central Maine (United States) by laser fluorination, and in situ by ion microprobe. Two types of garnet are recognized, magmatic and locally derived peritectic. Traverses of some single crystals show both gradual and abrupt changes of δ18O(garnet), commonly >1‰, while other garnet grains are isotopically homogeneous. Rimward increase of δ18O in many crystals indicates that garnet grew while high δ18O metamorphic wall rocks were assimilated. Peritectic grains have a complementary record of the transfer of high δ18O melts to the plutons. In some rocks, δ18O varies among neighboring grains, evidence that crystals grew episodically or were juxtaposed from different sources during magma mixing. Garnet faithfully records changing magmatic δ18O, and is a valuable tool to decipher magma petrogenesis. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.