Are oceanic fracture zones locked and strong or weak?: New evidence for volcanic activity and weakness

Abstract

Research Article| March 01, 1986 Are oceanic fracture zones locked and strong or weak?: New evidence for volcanic activity and weakness Allen Lowrie; Allen Lowrie 1Ocean Projects Division, NAVOCEANO, NASA Space Technology Laboratory Station, Mississippi 39529 Search for other works by this author on: GSW Google Scholar Christian Smoot; Christian Smoot 2Bathymetry Division, NAVOCEANO, NASA Space Technology Laboratory Station, Mississippi 39529 Search for other works by this author on: GSW Google Scholar Rodey Batiza Rodey Batiza 3Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St. Louis, Missouri 63130 Search for other works by this author on: GSW Google Scholar Author and Article Information Allen Lowrie 1Ocean Projects Division, NAVOCEANO, NASA Space Technology Laboratory Station, Mississippi 39529 Christian Smoot 2Bathymetry Division, NAVOCEANO, NASA Space Technology Laboratory Station, Mississippi 39529 Rodey Batiza 3Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St. Louis, Missouri 63130 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1986) 14 (3): 242–245. https://doi.org/10.1130/0091-7613(1986)14<242:AOFZLA>2.0.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 Allen Lowrie, Christian Smoot, Rodey Batiza; Are oceanic fracture zones locked and strong or weak?: New evidence for volcanic activity and weakness. Geology 1986;; 14 (3): 242–245. doi: https://doi.org/10.1130/0091-7613(1986)14<242:AOFZLA>2.0.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 Traditionally, oceanic fracture zones and other lithospheric and crustal faults have been viewed as zones of weakness that are vulnerable to seismic and volcanic activity. This notion has recently been questioned on the basis of evidence showing that initial depth offsets (scarp height) across some Pacific fracture zones are preserved even after ∼100 m.y. of differential subsidence. This evidence suggests that some parts of oceanic fracture zones are locked shortly) after they drift away from ridge-transform intersections. Because the fracture zones seem to be strong welds, differential cooling stresses cause flexure in the lithosphere on both sides of the fracture. In this paper we briefly review the seemingly contradictory evidence for the thermomechanical characteristics of oceanic fracture zones (locked and strong vs. slipped and weak) and present new evidence indicating that parts of some fracture zones are volcanically active. Volcanism is an indication of relative weakness because strain and failure are required to open volcanic conduits. This and other evidence for the inherent weakness of fracture zones can be reconciled with evidence for strength if different segments of fracture zones exhibit contrasting thermomechanical behavior. More data are needed to determine whether this is so and whether there are systematic patterns of distribution for weak and strong parts of individual fracture zones. 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.