Evidence against subduction-related magmatism for the Jiaoziyan Gabbro, Northern Dabie Shan, China
Journal
Geology
Journal Volume
28
Journal Issue
10
Pages
943-946
Date Issued
2000
Author(s)
Abstract
Research Article| October 01, 2000 Evidence against subduction-related magmatism for the Jiaoziyan Gabbro, northern Dabie Shan, China Chin-Ho Tsai; Chin-Ho Tsai 1Department of Geology, National Taiwan University, Taipei 106, Taiwan Search for other works by this author on: GSW Google Scholar Ching-Hua Lo; Ching-Hua Lo 1Department of Geology, National Taiwan University, Taipei 106, Taiwan Search for other works by this author on: GSW Google Scholar Juhn G. Liou; Juhn G. Liou 2Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305, USA Search for other works by this author on: GSW Google Scholar Bor-ming Jahn Bor-ming Jahn 3Geosciences Rennes, Centre National de la Recherche Scientific, Université de Rennes 1, 35042, Rennes cedex, France Search for other works by this author on: GSW Google Scholar Author and Article Information Chin-Ho Tsai 1Department of Geology, National Taiwan University, Taipei 106, Taiwan Ching-Hua Lo 1Department of Geology, National Taiwan University, Taipei 106, Taiwan Juhn G. Liou 2Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305, USA Bor-ming Jahn 3Geosciences Rennes, Centre National de la Recherche Scientific, Université de Rennes 1, 35042, Rennes cedex, France Publisher: Geological Society of America Received: 24 Mar 2000 Revision Received: 20 Jun 2000 Accepted: 19 Jul 2000 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2000) 28 (10): 943–946. https://doi.org/10.1130/0091-7613(2000)282.0.CO;2 Article history Received: 24 Mar 2000 Revision Received: 20 Jun 2000 Accepted: 19 Jul 2000 First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Chin-Ho Tsai, Ching-Hua Lo, Juhn G. Liou, Bor-ming Jahn; Evidence against subduction-related magmatism for the Jiaoziyan Gabbro, northern Dabie Shan, China. Geology 2000;; 28 (10): 943–946. doi: https://doi.org/10.1130/0091-7613(2000)282.0.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 largest gabbroic intrusion, Jiaoziyan, in the Northern Orthogneiss of the Dabie Shan was investigated to test whether such intrusions represent arc-related or collision-related magma, as postulated in recent regional tectonic models. The Jiaoziyan intrusions comprise a gabbro-monzogabbro suite and are locally characterized by cumulus textured anhydrous silicates. Petrologic indications against arc magmatism include (1) coexisting olivine-plagioclase compositions beyond the documented range of arc gabbros, and (2) a compositional trend of Al/Ti ratios in the gabbroic clinopyroxenes that is significantly different from subduction-related gabbros worldwide. In contrast, the Jiaoziyan rocks are mineralogically similar to rift gabbros. Geochronologic and geometric arguments against collision-related magmatism (i.e., as a consequence of slab breakoff) include the following: (1) crystallization of the Jiaoziyan mafic intrusion postdated the Triassic (245–240 Ma) subduction and peak orogenic metamorphism by ∼100 m.y. and (2) the rocks of the Dabie Cretaceous magmatic suite, including Jiaoziyan, are on the footwall plate, rather than on the hanging wall, of the Triassic subduction-zone framework and do not show a linear distribution. These observations argue that the voluminous Early Cretaceous magmatism in the Northern Orthogneiss is geodynamically unrelated to the Qinling-Dabie orogeny, but was caused by extensional tectonism related to regional magmatic underplating beneath the thinned Dabie crust. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
SDGs
Type
journal article