Fault-zone evolution in layered basalt sequences: A case study from the Faroe Islands, NE Atlantic margin

Abstract

Research Article| July 01, 2012 Fault-zone evolution in layered basalt sequences: A case study from the Faroe Islands, NE Atlantic margin R.J. Walker; R.J. Walker † 1School of Earth and Ocean Sciences, Cardiff University, Main Building, Cardiff CF10 3AT, UK2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK †E-mail: walkerrj@cardiff.ac.uk Search for other works by this author on: GSW Google Scholar R.E. Holdsworth; R.E. Holdsworth 2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK Search for other works by this author on: GSW Google Scholar J. Imber; J. Imber 2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK Search for other works by this author on: GSW Google Scholar D. Ellis D. Ellis 3Statoil (U.K.) Limited, One Kingdom Street, London W2 6BD, UK Search for other works by this author on: GSW Google Scholar Author and Article Information R.J. Walker † 1School of Earth and Ocean Sciences, Cardiff University, Main Building, Cardiff CF10 3AT, UK2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK R.E. Holdsworth 2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK J. Imber 2Department of Earth Sciences, Durham University, Science Labs, Durham DH1 3LE, UK D. Ellis 3Statoil (U.K.) Limited, One Kingdom Street, London W2 6BD, UK †E-mail: walkerrj@cardiff.ac.uk Publisher: Geological Society of America Received: 05 Mar 2011 Revision Received: 01 Nov 2011 Accepted: 08 Nov 2011 First Online: 08 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2012 Geological Society of America GSA Bulletin (2012) 124 (7-8): 1382–1393. https://doi.org/10.1130/B30512.1 Article history Received: 05 Mar 2011 Revision Received: 01 Nov 2011 Accepted: 08 Nov 2011 First Online: 08 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 R.J. Walker, R.E. Holdsworth, J. Imber, D. Ellis; Fault-zone evolution in layered basalt sequences: A case study from the Faroe Islands, NE Atlantic margin. GSA Bulletin 2012;; 124 (7-8): 1382–1393. doi: https://doi.org/10.1130/B30512.1 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 SocietyGSA Bulletin Search Advanced Search Abstract Few studies have focused on the geological characterization of exhumed subsurface faults and fractures within continental flood basalt provinces. We present field and microstructural observations of basalt-hosted fractures and faults from the Faroe Islands, NE Atlantic margin. For a given displacement, the thickness of these highly mineralized faults varies by over three orders of magnitude. Fault-zone thickness and displacement data from the Faroe Islands span nearly four orders of magnitude in displacement, but there is no strong positive correlation between fault-zone thickness and displacement. Fault-rock characterization reveals important breccia distinctions, including collapse/infill, crush/wear/abrasion, and implosion breccias, each with a respective increase in sealing potential. Collapse/infill breccias indicate sustained fluid-migration pathways, as they require open, subterranean cavities that are formed faster than mineral precipitation can seal them. Crush/wear/abrasion and implosion breccias record crack-seal behavior during successive slip events. Despite having distinctly different fault-rock assemblages, fault-zone thickness and displacement data from basalt-hosted faults are indistinguishable from comparable data obtained from sediment-hosted faults. This observation suggests that the first-order controls on fault development are the same in layered basalts and sediments, namely, fault surface bifurcation and linkage, asperity removal, and the accommodation of geometrically necessary strains in the wall rocks. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.