Neogene deformation in northern Tunisia: Origin of the eastern Atlas by microplate—continental margin collision

Abstract

Research Article| April 01, 1980 Neogene deformation in northern Tunisia: Origin of the eastern Atlas by microplate—continental margin collision CURTIS R. COHEN; CURTIS R. COHEN 1Lamont-Doherty Geological Observatory and Department of Geological Sciences, Columbia University, Palisades, New York 10964 Search for other works by this author on: GSW Google Scholar STEVEN SCHAMEL; STEVEN SCHAMEL 2Lamont-Doherty Geological Observatory of Columbia University, Palisades, New York 10964 and Department of Geology, Lafayette College, Easton, Pennsylvania 18042 Search for other works by this author on: GSW Google Scholar PATTI BOYD-KAYGI PATTI BOYD-KAYGI 3Department of Geological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 Search for other works by this author on: GSW Google Scholar Author and Article Information CURTIS R. COHEN 1Lamont-Doherty Geological Observatory and Department of Geological Sciences, Columbia University, Palisades, New York 10964 STEVEN SCHAMEL 2Lamont-Doherty Geological Observatory of Columbia University, Palisades, New York 10964 and Department of Geology, Lafayette College, Easton, Pennsylvania 18042 PATTI BOYD-KAYGI 3Department of Geological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1980) 91 (4): 225–237. https://doi.org/10.1130/0016-7606(1980)91<225:NDINTO>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 Tools Icon Tools Get Permissions Search Site Citation CURTIS R. COHEN, STEVEN SCHAMEL, PATTI BOYD-KAYGI; Neogene deformation in northern Tunisia: Origin of the eastern Atlas by microplate—continental margin collision. GSA Bulletin 1980;; 91 (4): 225–237. doi: https://doi.org/10.1130/0016-7606(1980)91<225:NDINTO>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 Detailed structural analysis in the southern Hédil region, northern Tunisia, suggests that the area is characterized by normal faulted, southeast-vergent and upright, box- to close-style folds. Fold nappes and imbricate thrust sheets postulated previously are absent in the Hedil, although thrust sheets do occur farther north in the Mogods and Kroumerie regions.A two-stage tectonic model is proposed: (1) middle Miocene progressive deformation involving initial buckle folding and later shear faulting in the Hédil, and southeast-directed thrusting in the Mogods and Kroumerie; and (2) postdeformation extensional faulting parallel to regional fold trends, bimodal (basalt-rhyolite) volcanism, and molasse deposition. Minor, post-Messinian southeast-vergent thrust faulting followed this extensional regime and continues to the present. Maximum principal compressive stress (σ1), horizontal and striking S38°E, is inferred for the middle Miocene deformation.The middle Miocene fold and thrust structures are related to the collision of the counterclockwise-rotating Corsica-Sardinia-Petit Kabylie plate with the Tunisian continental margin. Following this collision, in the Tortonian, the development of a sphenochasm spreading system to the west of the present-day Straits of Sardinia produced the extensional regime that prevailed in northern Tunisia. As spreading continued, the Petit Kabylie rotated clockwise away from Sardinia. Movement ceased when the Petit Kabylie collided with the Algerian continental margin. 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.