The long-term topographic response of a continent adjacent to a hyperextended margin: A case study from Scandinavia

Research Article| January 01, 2013 The long-term topographic response of a continent adjacent to a hyperextended margin: A case study from Scandinavia T.F. Redfield; T.F. Redfield † 1Geological Survey of Norway, Leiv Eriksons vei 39, N-7491 Trondheim, Norway †E-mail: tim.redfield@ngu.no Search for other works by this author on: GSW Google Scholar P.T. Osmundsen P.T. Osmundsen 1Geological Survey of Norway, Leiv Eriksons vei 39, N-7491 Trondheim, Norway2Department of Arctic Geology, University Centre in Svalbard, N-9171, Longyearbyen, Norway Search for other works by this author on: GSW Google Scholar Author and Article Information T.F. Redfield † 1Geological Survey of Norway, Leiv Eriksons vei 39, N-7491 Trondheim, Norway P.T. Osmundsen 1Geological Survey of Norway, Leiv Eriksons vei 39, N-7491 Trondheim, Norway2Department of Arctic Geology, University Centre in Svalbard, N-9171, Longyearbyen, Norway †E-mail: tim.redfield@ngu.no Publisher: Geological Society of America Received: 10 Mar 2012 Revision Received: 22 Jul 2012 Accepted: 09 Aug 2012 First Online: 08 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 2013 Geological Society of America GSA Bulletin (2013) 125 (1-2): 184–200. https://doi.org/10.1130/B30691.1 Article history Received: 10 Mar 2012 Revision Received: 22 Jul 2012 Accepted: 09 Aug 2012 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 T.F. Redfield, P.T. Osmundsen; The long-term topographic response of a continent adjacent to a hyperextended margin: A case study from Scandinavia. GSA Bulletin 2013;; 125 (1-2): 184–200. doi: https://doi.org/10.1130/B30691.1 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 We present data that link Scandinavia's passive-margin domains under a unified system invoking isostatically driven, postextension phase vertical adjustments to severe crustal thinning. Topographic and geological data indicate that the relative location of the first landward occurrence of total crustal embrittlement or deformation coupling—the Taper Break—controlled and continues to control Scandinavia's post-thinning geomorphic evolution. Formed during Late Jurassic or Early Cretaceous thinning, yet marked today by seismicity, the Taper Break closely approximates the boundary between (1) less-stretched lithosphere that increases in rigidity both toward land and through postrift time, and (2) the highly attenuated, pervasively faulted, permanently weakened lithosphere of the distal margin. Following the stretching, thinning, and exhumation phases proposed by other workers, an accommodation phase is warranted. Commencing during "sag" basin time and continuing today, it is probably driven by thermal cooling and mass transfer from the escarpment to the basins offshore. The accommodation phase does not entirely coincide with the traditional postrift phase as the former may contain the latter. During accommodation, the original synrift escarpments can be eroded to very low base levels. Sharply tapered margin segments can undergo subsequent rejuvenation by out-of-sequence normal faulting and footwall uplift, probably in response to tensile bending stresses engendered by lithospheric-scale flexure. Accommodation-phase uplift at passive margins is the inexorable and penultimate phase of hyperextension, and may perhaps be followed by the onset of subduction localized by the weakened lithosphere of the distal margin and the ocean-continent transition. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.