Rare earth, major, and trace element composition of Monterey and DSDP chert and associated host sediment; assessing the influence of chemical fractionation during diagenesis

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doi: 10.1016/0016-7037(92)90351-I
Author(s): Murray, Richard W.; Buchholtz ten Brink, Marilyn R.; Gerlach, David C.; Russ, G. Price, III; Jones, David L.
Author Affiliation(s): Primary:
Univ. Calif. at Berkeley, Dep. Geol. and Geophys., Berkeley, CA, United States
Lawrence Livermore Natl. Lab., United States
Volume Title: Geochimica et Cosmochimica Acta
Source: Geochimica et Cosmochimica Acta, 56(7), p.2657-2671. Publisher: Pergamon, Oxford, International. ISSN: 0016-7037 CODEN: GCACAK
Note: In English. 68 refs.; 3 tables
Summary: Major and trace element analyses are presented of diagenetic cherts and associated host sediments from the Monterey formation and five DSDP sites, with the object of assessing geochemical changes and relative fractionations between diagenetic chert and the host sediments.The results confirm the greater absolute concentration of SiO2 in chert with enhanced Si/Al ratios compared with the host sediments. These differences suggest precursor sediment heterogeneity and/or diagenetic fractionation of SiO2, but biogenic dissolution and transport of SiO2 and subsequent precipitation of SiO2 in chert is suggested to be the main process. During diagenetic formation of cherts the addition of SiO2 is accompanied in some cases by the removal of carbonate and phosphate. Sr and Ba in DSDP cherts are depleted with respect to Al due to diagenetic biogenic activity; Mn also is affected. The Ce anomaly recorded in Monterey and DSDP chert is not affected by diagenesis; slight Eu/Eu* decrease in DSDP chert may reflect the small loss in feldspar, chert being essentially monomineralic. Slight fractionation of REE during diagenesis indicates that the REE composition of a sedimentary rock may not represent that of the primary sediment.
Year of Publication: 1992
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 02 Geochemistry; 06 Petrology, Sedimentary; California; Cenozoic; Chemical composition; Chemical fractionation; Chemically precipitated rocks; Chert; Controls; Deep Sea Drilling Project; Diagenesis; Geochemistry; IPOD; Leg 62; Leg 69; Major elements; Metals; Miocene; Monterey Formation; Neogene; Oceanography; Pacific Ocean; Rare earths; Sedimentary petrology; Sedimentary rocks; Sediments; Tertiary; Trace elements; United States
Coordinates: N200000 N400000 E1792000 E1735000
N011000 N020000 W0834000 W0835000
Record ID: 1992056307
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from Mineralogical Abstracts, United Kingdom, Twickenham, United Kingdom