Absolute fault and crustal strength from wedge tapers

Research Article| December 01, 2007 Absolute fault and crustal strength from wedge tapers John Suppe John Suppe 1Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA Search for other works by this author on: GSW Google Scholar Author and Article Information John Suppe 1Department of Geosciences, Princeton University, Princeton, New Jersey 08544, USA Publisher: Geological Society of America Received: 21 May 2007 Revision Received: 31 Jul 2007 Accepted: 02 Aug 2007 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 The Geological Society of America, Inc. Geology (2007) 35 (12): 1127–1130. https://doi.org/10.1130/G24053A.1 Article history Received: 21 May 2007 Revision Received: 31 Jul 2007 Accepted: 02 Aug 2007 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation John Suppe; Absolute fault and crustal strength from wedge tapers. Geology 2007;; 35 (12): 1127–1130. doi: https://doi.org/10.1130/G24053A.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 SocietyGeology Search Advanced Search Abstract The strengths of mountain belts and major faults have been notoriously difficult to constrain and there is ongoing debate over the controlling mechanisms and stress magnitudes. Here we show that the strengths of active thrust-belt wedges and their basal detachments can be directly determined from the covariation of surface slope α with detachment dip β, without strong assumptions about the specific strength-controlling mechanisms. Even a single taper measurement (α, β) can strongly constrain the set of possible wedge and detachment strengths. This theory is tested with dry sand wedges and then applied to the Niger delta thrust belt, the active Taiwan mountain belt, and the thrust that slipped in the M = 7.6 Chi-Chi earthquake. Their basal detachments are shown to be exceedingly weak, with effective coefficients of friction (0.04–0.1) that are an order of magnitude less than most laboratory friction coefficients (0.6–0.85). In contrast, these wedges are moderately strong internally, within the range of pressure-dependent strengths in deep boreholes. These results confirm the existence of exceedingly weak faults and strong crust, which raises important causal questions. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.