Preuplift joints in granites: Evidence for subcritical and postcritical fracture growth

Abstract

Research Article| February 01, 2003 Preuplift joints in granites: Evidence for subcritical and postcritical fracture growth Dov Bahat; Dov Bahat 1Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel Search for other works by this author on: GSW Google Scholar Peter Bankwitz; Peter Bankwitz 2Gutenberg Strasse 60, 14467 Potsdam, Germany Search for other works by this author on: GSW Google Scholar Elfriede Bankwitz Elfriede Bankwitz 2Gutenberg Strasse 60, 14467 Potsdam, Germany Search for other works by this author on: GSW Google Scholar Author and Article Information Dov Bahat 1Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, Beer Sheva 84105, Israel Peter Bankwitz 2Gutenberg Strasse 60, 14467 Potsdam, Germany Elfriede Bankwitz 2Gutenberg Strasse 60, 14467 Potsdam, Germany Publisher: Geological Society of America Received: 20 Feb 2001 Revision Received: 01 Apr 2002 Accepted: 02 Apr 2002 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2003) 115 (2): 148–165. https://doi.org/10.1130/0016-7606(2003)115<0148:PJIGEF>2.0.CO;2 Article history Received: 20 Feb 2001 Revision Received: 01 Apr 2002 Accepted: 02 Apr 2002 First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Dov Bahat, Peter Bankwitz, Elfriede Bankwitz; Preuplift joints in granites: Evidence for subcritical and postcritical fracture growth. GSA Bulletin 2003;; 115 (2): 148–165. doi: https://doi.org/10.1130/0016-7606(2003)115<0148:PJIGEF>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 SocietyGSA Bulletin Search Advanced Search Abstract This study relates to jointing in granite that took place in the crust before uplift, thus offering an insight into paleo–fracture processes. Our investigation reveals a unique set of joints within granite of the South Bohemian Pluton exposed in the Borsov Quarry, southeast of Prague in the Czech Republic. These joints occur in close proximity and exhibit a great variety of fracture-surface morphologies. The joints in the Borsov granite may be divided into four groups based on fractographic features: (1) partial mirror planes without fringes, (2) mirror planes rimmed by en echelon fringes, (3) complex en echelon fringes, and (4) hackled fringes. On the basis of theoretical, experimental, and fractographic data obtained in outcrops, we have constructed a curve for the change in crack velocity V as a function of the stress-intensity factor KI, and we have plotted the various joints in the Borsov granite on this curve. The spread of the joints along the curve indicates that the joints terminated under widely different physical conditions, possibly responding to repeated extensional events and different fracture mechanisms. Hence, a new quantitative method of joint classification is introduced.Such a great variety of fractographic features is unknown from joint sets that occur in a single quarry in sedimentary rock, because their formation always relates to a particular fracture mechanism. We argue that the joints in the Borsov granite formed before uplift in a fluid-enriched environment, while the granite responded to diverse, local effective-stress conditions. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.