Contrasting tectonic styles in the northern Grenville province: Implications for the dynamics of orogenic fronts

Abstract

Research Article| December 01, 1993 Contrasting tectonic styles in the northern Grenville province: Implications for the dynamics of orogenic fronts T. Rivers; T. Rivers 1Department of Earth Sciences, Memorial University, St. John's, Newfoundland A1B 3X5, Canada Search for other works by this author on: GSW Google Scholar J.A.M. van Gool; J.A.M. van Gool 1Department of Earth Sciences, Memorial University, St. John's, Newfoundland A1B 3X5, Canada Search for other works by this author on: GSW Google Scholar J. N. Connelly J. N. Connelly 1Department of Earth Sciences, Memorial University, St. John's, Newfoundland A1B 3X5, Canada Search for other works by this author on: GSW Google Scholar Geology (1993) 21 (12): 1127–1130. https://doi.org/10.1130/0091-7613(1993)021<1127:CTSITN>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation T. Rivers, J.A.M. van Gool, J. N. Connelly; Contrasting tectonic styles in the northern Grenville province: Implications for the dynamics of orogenic fronts. Geology 1993;; 21 (12): 1127–1130. doi: https://doi.org/10.1130/0091-7613(1993)021<1127:CTSITN>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 In western Labrador, tectonic elements of the parautochthonous belt of the northern Grenville orogen include a regional, mid-crustal, thin-skinned, metamorphic fold-thrust belt structurally overlain by a thick-skinned thrust sheet with a high-pressure metamorphic signature. In central Ontario, the parautochthonous belt is composed of a major reverse-sense shear zone, along which deep crustal rocks have been uplifted and exhumed. Tectonic models for both areas involve crustal shortening by delamination in the lower crust and tectonically driven exhumation up a crustal-scale ramp. The fold-thrust belt northwest of the ramp in Labrador is a result of the development of critical topography in the thrust wedge at the top of the ramp and the accretion of thrust slices to the base of the wedge during its propagation onto the foreland. The fold-thrust belt is absent in Ontario because syntectonic erosion of the thrust wedge prevented the development of critical topography. 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.