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Diagenetic formation of bedded chert: Evidence from chemistry of the chert-shale couplet

1992; Geological Society of America; Volume: 20; Issue: 3 Linguagem: Inglês

10.1130/0091-7613(1992)020 2.3.co;2

1943-2682

Richard W. Murray, David L. Jones, Marilyn R. Buchholtz ten Brink,

Geology and Paleoclimatology Research

Research Article| March 01, 1992 Diagenetic formation of bedded chert: Evidence from chemistry of the chert-shale couplet Richard W. Murray; Richard W. Murray 1Department of Geology and Geophysics, University of California, Berkeley, California 94720 Search for other works by this author on: GSW Google Scholar David L. Jones; David L. Jones 1Department of Geology and Geophysics, University of California, Berkeley, California 94720 Search for other works by this author on: GSW Google Scholar Marilyn R. Buchholtz ten Brink Marilyn R. Buchholtz ten Brink 2Earth Sciences Department, Lawrence Livermore National Laboratory, Livermore, California 94550 Search for other works by this author on: GSW Google Scholar Author and Article Information Richard W. Murray 1Department of Geology and Geophysics, University of California, Berkeley, California 94720 David L. Jones 1Department of Geology and Geophysics, University of California, Berkeley, California 94720 Marilyn R. Buchholtz ten Brink 2Earth Sciences Department, Lawrence Livermore National Laboratory, Livermore, California 94550 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1992) 20 (3): 271–274. https://doi.org/10.1130/0091-7613(1992)020 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 MailTo Tools Icon Tools Get Permissions Search Site Citation Richard W. Murray, David L. Jones, Marilyn R. Buchholtz ten Brink; Diagenetic formation of bedded chert: Evidence from chemistry of the chert-shale couplet. Geology 1992;; 20 (3): 271–274. doi: https://doi.org/10.1130/0091-7613(1992)020 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 Theories concerning the formation of bedded chert traditionally have emphasized either depositional or diagenetic processes. Major and rare earth element data from Franciscan assemblage (Mesozoic) and Claremont Formation (Miocene) bedded chert sequences, along with physical observations such as the presence of rare and highly corroded radiolarians in shale interbeds, are most consistent with a dominantly diagenetic origin of chert-shale couplets and are incompatible with many depositional theories. Chemical distributions between Franciscan and Claremont bedded chert=shale closely match chemical fractionations recorded by Monterey Formation and Deep Sea Drilling Project-sampled cherts formed by diagenetic SiO2 dissolution, transport, and reprecipitation, suggesting that diagenetic migration of SiO2 from proto-shale to proto-chert is also largely responsible for chert-shale couplets. Identical Ce anomalies (Ce/Ce*) found in immediately adjacent chert-shale layers indicate that turbidites or other transport mechanisms are not responsible for the alternating beds. Neither the chemistry of the chert-shale couplet nor the overall stratigraphy of the sequences is consistent with couplet formation being caused by productivity fluctuations. Chemical mass balance calculations reconstructing the total bulk sediment composition suggest that modern siliceous sequences do not contain enough labile biogenic SiO2 to form entire stratigraphies of bedded chert. 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.