Biogenic Sedimentation and Alteration of Argillaceous Sediments in Shallow Marine Environments

Research Article| September 01, 1975 Biogenic Sedimentation and Alteration of Argillaceous Sediments in Shallow Marine Environments WAYNE A. PRYOR WAYNE A. PRYOR 1H. N. Fisk Laboratory of Sedimentology, University of Cincinnati, Cincinnati, Ohio 45221 Search for other works by this author on: GSW Google Scholar Author and Article Information WAYNE A. PRYOR 1H. N. Fisk Laboratory of Sedimentology, University of Cincinnati, Cincinnati, Ohio 45221 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1975) 86 (9): 1244–1254. https://doi.org/10.1130/0016-7606(1975)862.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation WAYNE A. PRYOR; Biogenic Sedimentation and Alteration of Argillaceous Sediments in Shallow Marine Environments. GSA Bulletin 1975;; 86 (9): 1244–1254. doi: https://doi.org/10.1130/0016-7606(1975)862.0.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 The feeding activities and excretory products of the marine decapod Callianassa major Say and the marine annelid Onuphis microcephala Hartman have been studied in shallow marine environments of the southern Atlantic and eastern Gulf of Mexico coasts of the United States. These filter-feeding organisms produce depositionally significant quantities of argillaceous fecal pellets that are transported and deposited as granular clay with hydraulically equivalent quartz sand grains. At average population densities observed in shallow marine environments, these organisms are calculated to be capable of removing and pelletizing approximately 12 metric tons of suspended materials per square kilometre per year and of depositing fecal pellet mud as thick as 4.5 mm yearly. Recent deposits of Onuphis pellets up to 30 cm thick and Callianassa pellets as thick as 60 cm have been observed.The complex, species-specific, sand-sized fecal pellets are composed of 80 to 90 percent clay-mineral particles and 5 to 10 percent undigested organic particles and small amounts of quartz sand and silt grains. The digestive systems of the organisms significantly alter the clay mineralogy of the sediments extracted from suspension, and Callianassa major produces fecal pellets of different clay-mineral compositions from fecal pellets produced by Onuphis microcephala. The digestive processes wholly or partly destroy chlorite. Mixed-layer clay minerals are partly destroyed, and kaolinite and illite are in part disordered. Fecal pellets, rich in organic matter, enter the coprophagic cycle where further clay-mineral alteration takes place. Decay of the organic matter creates microreducing conditions within the pellets, thus promoting the processes of glauconitization.Whereas flocculation is the important process in the deposition of argillaceous sediments in deltaic environments, biogenic pelletization may be the most important process in depositing argillaceous sediments in shallow marine interdeltaic environments. 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.