Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications

Abstract

Research Article| July 01, 1992 Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications G. Nelson Eby G. Nelson Eby 1Department of Earth Sciences, University of Massachusetts, Lowell, Massachusetts 01854 Search for other works by this author on: GSW Google Scholar Author and Article Information G. Nelson Eby 1Department of Earth Sciences, University of Massachusetts, Lowell, Massachusetts 01854 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1992) 20 (7): 641–644. https://doi.org/10.1130/0091-7613(1992)020<0641:CSOTAT>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 Email Permissions Search Site Citation G. Nelson Eby; Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications. Geology 1992;; 20 (7): 641–644. doi: https://doi.org/10.1130/0091-7613(1992)020<0641:CSOTAT>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 The A-type granitoids can be divided into two chemical groups. The first group (A1) is characterized by element ratios similar to those observed for oceanic-island basalts. The second group (A2) is characterized by ratios that vary from those observed for continental crust to those observed for island-arc basalts. It is proposed that these two types have very different sources and tectonic settings. The A1 group represents differentiates of magmas derived from sources like those of oceanic-island basalts but emplaced in continental rifts or during intraplate magmatism. The A2 group represents magmas derived from continental crust or underplated crust that has been through a cycle of continent-continent collision or island-arc magmatism. 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.