Cool-water carbonates in a paleoequatorial shallow-water environment: The paradox of the Auernig cyclic sediments (Upper Pennsylvanian, Carnic Alps, Austria-Italy) and its implications

Abstract

Research Article| July 01, 2002 Cool-water carbonates in a paleoequatorial shallow-water environment: The paradox of the Auernig cyclic sediments (Upper Pennsylvanian, Carnic Alps, Austria-Italy) and its implications Elias Samankassou Elias Samankassou 1Département de Géosciences, Géologie et Paléontologie, Université de Fribourg, Pérolles, CH-1700 Fribourg, Switzerland Search for other works by this author on: GSW Google Scholar Author and Article Information Elias Samankassou 1Département de Géosciences, Géologie et Paléontologie, Université de Fribourg, Pérolles, CH-1700 Fribourg, Switzerland Publisher: Geological Society of America Received: 06 Feb 2002 Revision Received: 29 Mar 2002 Accepted: 02 Apr 2002 First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2002) 30 (7): 655–658. https://doi.org/10.1130/0091-7613(2002)030<0655:CWCIAP>2.0.CO;2 Article history Received: 06 Feb 2002 Revision Received: 29 Mar 2002 Accepted: 02 Apr 2002 First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Elias Samankassou; Cool-water carbonates in a paleoequatorial shallow-water environment: The paradox of the Auernig cyclic sediments (Upper Pennsylvanian, Carnic Alps, Austria-Italy) and its implications. Geology 2002;; 30 (7): 655–658. doi: https://doi.org/10.1130/0091-7613(2002)030<0655:CWCIAP>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 Distinct parts of limestones within the upper Paleozoic Auernig Group of the Carnic Alps, Austria and Italy, are characteristic of cool-water carbonates. The Carnic Alps were between 5°N and 10°S paleolatitude during the late Carboniferous, a position confirmed by dasyclad algae and fossil plants. The floral association, occurrence of coal seams, and absence of evaporites indicate a humid tropical environment. The entire section lacks abiotic components of typical warm-water limestones: no ooids and no aggregates occur within the Auernig Group. Parts of the limestones show, surprisingly, a cool-water association of high-diversity bryozoans, brachiopods, crinoids, red algae, sponge spicules, and entomozoan ostracodes. The genesis of these limestones, atypical for a paleoequatorial setting, cannot be explained by changes in salinity, bathymetry, or terrigenous input. The water temperature, possibly linked with upwelling, nutrient supply, and paleoceanographic currents, is the most convincing cause of this unusual association. Paleoceanographic changes are interpreted as linked to contemporaneous glaciation-deglaciation cycles in Gondwana. This paper shows that cool-water carbonates in shallow-water environments are not necessarily nontropical, as generally interpreted. Future studies should consider water temperature, oceanic circulation, and availability of nutrients, supplementary to bathymetry, salinity, and latitude-related climate in interpretation of carbonate components. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.