Syn-Acadian emplacement model for the South Mountain batholith, Meguma Terrane, Nova Scotia: Magnetic fabric and structural analyses

Abstract

Research Article| October 01, 1997 Syn-Acadian emplacement model for the South Mountain batholith, Meguma Terrane, Nova Scotia: Magnetic fabric and structural analyses Keith Benn; Keith Benn 1Ottawa-Carleton Geoscience Centre and Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Search for other works by this author on: GSW Google Scholar Richard J. Horne; Richard J. Horne 2Nova Scotia Department of Natural Resources, Halifax, Nova Scotia B3J 2T9, Canada Search for other works by this author on: GSW Google Scholar Daniel J. Kontak; Daniel J. Kontak 2Nova Scotia Department of Natural Resources, Halifax, Nova Scotia B3J 2T9, Canada Search for other works by this author on: GSW Google Scholar Geoffrey S. Pignotta; Geoffrey S. Pignotta 3Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Search for other works by this author on: GSW Google Scholar Neil G. Evans Neil G. Evans 3Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Search for other works by this author on: GSW Google Scholar Author and Article Information Keith Benn 1Ottawa-Carleton Geoscience Centre and Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Richard J. Horne 2Nova Scotia Department of Natural Resources, Halifax, Nova Scotia B3J 2T9, Canada Daniel J. Kontak 2Nova Scotia Department of Natural Resources, Halifax, Nova Scotia B3J 2T9, Canada Geoffrey S. Pignotta 3Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Neil G. Evans 3Department of Geology, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1997) 109 (10): 1279–1293. https://doi.org/10.1130/0016-7606(1997)109<1279:SAEMFT>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Keith Benn, Richard J. Horne, Daniel J. Kontak, Geoffrey S. Pignotta, Neil G. Evans; Syn-Acadian emplacement model for the South Mountain batholith, Meguma Terrane, Nova Scotia: Magnetic fabric and structural analyses. GSA Bulletin 1997;; 109 (10): 1279–1293. doi: https://doi.org/10.1130/0016-7606(1997)109<1279:SAEMFT>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 SocietyGSA Bulletin Search Advanced Search Abstract The anisotropy of magnetic susceptibility and the structural geology of the Late Devonian South Mountain batholith (Meguma Terrane, Nova Scotia) are used to characterize its emplacement and structural evolution. The South Mountain batholith is the largest peraluminous granitoid complex within the Appalachian orogen. It is a composite batholith made up of stage 1 granodiorites and monzogranites and stage 2 leucomonzogranites and leucogranites. The anisotropy of magnetic susceptibility was used to map the biotite petrofabric at the scale of the batholith. The biotite fabric pattern is similar to the pattern of folding and shearing of the feldspar megacryst foliation, documented at the outcrop scale. In the stage 1 plutons, the magnetic foliation is deformed into a girdle about the horizontal, northeast-southwest—trending magnetic lineation, which is parallel to regional fold axes and extension lineations in the country rocks. In the stage 2 plutons, a horizontal northeast-southwest– to east-west–trending magnetic lineation is also present, but the horizontal orientation of the magnetic foliation is widely preserved. The folding and shearing of the foliations and the horizontal northeast-southwest–trending lineation that is pervasive throughout the South Mountain batholith are interpreted to record Acadian tectonic deformation of the plutons as they crystallized. Acadian deformation continued during the latest stages of crystallization, resulting in the localization of mineral deposits and greisens along shear zones, faults, and joints. A model is presented for the syntectonic emplacement of the South Mountain batholith as a laccolithic complex. 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.