Upper Cretaceous–Paleocene magnetic stratigraphy at Gubbio, Italy I. Lithostratigraphy and sedimentology

Abstract

Research Article| March 01, 1977 Upper Cretaceous–Paleocene magnetic stratigraphy at Gubbio, Italy I. Lithostratigraphy and sedimentology MICHAEL A. ARTHUR; MICHAEL A. ARTHUR 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08540 Search for other works by this author on: GSW Google Scholar ALFRED G. FISCHER ALFRED G. FISCHER 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08540 Search for other works by this author on: GSW Google Scholar Author and Article Information MICHAEL A. ARTHUR 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08540 ALFRED G. FISCHER 1Department of Geological and Geophysical Sciences, Princeton University, Princeton, New Jersey 08540 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1977) 88 (3): 367–371. https://doi.org/10.1130/0016-7606(1977)88<367:UCMSAG>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 MailTo Tools Icon Tools Get Permissions Search Site Citation MICHAEL A. ARTHUR, ALFRED G. FISCHER; Upper Cretaceous–Paleocene magnetic stratigraphy at Gubbio, Italy I. Lithostratigraphy and sedimentology. GSA Bulletin 1977;; 88 (3): 367–371. doi: https://doi.org/10.1130/0016-7606(1977)88<367:UCMSAG>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 An essentially complete section of middle Cretaceous to Paleocene, calcareous, pelagic sediments is exposed at Gubbio, in the Umbrian Apennines of Italy. This, the first of five papers, presents the lithostratigraphic and sedimentological basis for subsequent discussions of biostratigraphy and magnetic stratigraphy. Biogenic coccolith-globigerinid oozes were deposited along with a constant but low background of fine terrigenous detritus at a mean sedimentation rate (compacted) of 6.6 m/m.y. from Albian to Eocene time; individual stages deviate from this by a factor of two. Short-term variations in carbonate input yielded a sequence of limestone beds punctuated by thin shale interbeds. These shale-limestone couplets accumulated in time spans between 20,000 and 100,000 yr, and the thin shales may represent up to one-half of the total time. Modification by diagenetic solution, tectonic shear, and weathering render shale interbeds unsuitable for magnetic work. The limestone beds, first bioturbated and then compacted and cemented during diagenesis, appear likely to have recorded magnetic history at intervals on the order of 50,000 yr, sufficient to provide a good record of polarity changes. Moderate to high states of oxidation prevailed except in Aptian-Albian and a portion of Turonian to Santonian times. 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.