Research Article| August 01, 2006 Revised age of Aleutian Island Arc formation implies high rate of magma production Brian R. Jicha; Brian R. Jicha 1Department of Geology and Geophysics, University of Wisconsin, Madison, Wisconsin 53706, USA Search for other works by this author on: GSW Google Scholar David W. Scholl; David W. Scholl 2Department of Geophysics, Stanford University, Stanford, California 95039, USA Search for other works by this author on: GSW Google Scholar Brad S. Singer; Brad S. Singer 3Department of Geology and Geophysics, University of Wisconsin, Madison, Wisconsin 53706, USA Search for other works by this author on: GSW Google Scholar Gene M. Yogodzinski; Gene M. Yogodzinski 4Department of Geological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA Search for other works by this author on: GSW Google Scholar Suzanne M. Kay Suzanne M. Kay 5Department of Earth & Atmospheric Sciences, Cornell University, Ithaca, New York 14853, USA Search for other works by this author on: GSW Google Scholar Geology (2006) 34 (8): 661–664. https://doi.org/10.1130/G22433.1 Article history received: 14 Nov 2005 rev-recd: 20 Mar 2006 accepted: 20 Mar 2006 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 Brian R. Jicha, David W. Scholl, Brad S. Singer, Gene M. Yogodzinski, Suzanne M. Kay; Revised age of Aleutian Island Arc formation implies high rate of magma production. Geology 2006;; 34 (8): 661–664. doi: https://doi.org/10.1130/G22433.1 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 Radioisotopic dating of subaerial and submarine volcanic and plutonic rocks from the Aleutian Island Arc provides insight into the timing of arc formation in the middle Eocene. Twenty-eight 40Ar/39Ar ages constrain the duration of arc magmatism to the last 46 m.y. Basaltic lavas from the Finger Bay volcanics, the oldest exposed rocks in the arc, gave an isochron age of 37.4 ± 0.6 Ma, which is 12–17 m.y. younger than a widely cited age of 55–50 Ma. Three main pulses of arc-wide magmatism occurred at 38–29, 16–11, and 6–0 Ma, which coincide with periods of intense magmatism in other western Pacific island arcs. Using the geochronology and volumetric estimates of crust generated and eroded over the last 46 m.y., we calculate a time-averaged magma production rate for the entire arc that exceeds previous estimates by almost an order of magnitude. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.