Phosphogenesis and weathering of shelf sediments from the southeastern United States: Implications for Miocene δ13C excursions and global cooling

Research Article| December 01, 1990 Phosphogenesis and weathering of shelf sediments from the southeastern United States: Implications for Miocene δ13C excursions and global cooling John S. Compton; John S. Compton 1Department of Marine Science, University of South Florida, St. Petersburg, Florida 33701 Search for other works by this author on: GSW Google Scholar Stephen W. Snyder; Stephen W. Snyder 2Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695 Search for other works by this author on: GSW Google Scholar David A. Hodell David A. Hodell 3Department of Geology, University of Florida, Gainesville, Florida 32611 Search for other works by this author on: GSW Google Scholar Author and Article Information John S. Compton 1Department of Marine Science, University of South Florida, St. Petersburg, Florida 33701 Stephen W. Snyder 2Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina 27695 David A. Hodell 3Department of Geology, University of Florida, Gainesville, Florida 32611 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1990) 18 (12): 1227–1230. https://doi.org/10.1130/0091-7613(1990)018<1227:PAWOSS>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation John S. Compton, Stephen W. Snyder, David A. Hodell; Phosphogenesis and weathering of shelf sediments from the southeastern United States: Implications for Miocene δ13C excursions and global cooling. Geology 1990;; 18 (12): 1227–1230. doi: https://doi.org/10.1130/0091-7613(1990)018<1227:PAWOSS>2.3.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 The enormous phosphorite deposits of the southeastern United States indicate intense upwelling but contain small amounts of organic carbon. We propose that deposition of organic-rich sediment on continental shelves in the southeastern United States and elsewhere during marine transgressions in the late Oligocene and early to middle Miocene resulted in global positive δ13C shifts and the formation of early diagenetic phosphorite. Multiple reworking and supergene weathering from subaerial exposure during Miocene marine regressions oxidized most of the organic carbon and resulted in the return of δ13C to its preexcursion value. The estimated phosphorite content of the southeastern United States requires sufficient organic carbon burial (>1015 kg carbon) to support a 1‰ δ13C excursion. We believe that our hypothesis may explain the relation among δ13C excursions, sea-level fluctuations, organic carbon burial, phosphogenic episodes, and possibly global cooling during the Cenozoic. 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.