Rare earth elements in Japan Sea sediments and diagenetic behavior of Ce/Ce*: Results from ODP Leg 127

Journal Article · Sun Sep 01 00:00:00 EDT 1991 · Geochimica et Cosmochimica Acta; (United States)

DOI:https://doi.org/10.1016/0016-7037(91)90365-C· OSTI ID:7278343

Murray, R W ^[1]; Buchholtz Ten Brink, M; Gerlach, D C; Price Russ, G III ^[2]; Brumsack, H J ^[3]

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1. Univ. of California, Berkeley (United States)
2. Lawrence Livermore National Laboratory, CA (United States)
3. Geochemisches Inst., Gottingen (Germany)

The relative effects of paleoceanographic and paleogeographic variations, sediment lithology, and diagenetic processes on the recorded rare earth element (REE) chemistry of Japan Sea sediments are evaluated by investigating REE total abundances and relative fractionations in 59 samples from Ocean Drilling Program Leg 127. REE total abundances ({Sigma}REE) in the Japan Sea are strongly dependent upon the paleoceanographic position of a given site with respect to terrigenous and biogenic sources. Ce/Ce* profiles at all three sites increase monotonically with depth, and record progressive diagenetic LREE fractionation. The observed Ce/Ce* record does not respond to changes in oxygenation state of the overlying water, and Ce/Ce* correlates slightly better with depth than with age. The downhole increase in Ce/Ce* at Site 794 and 797 is a passive response to diagenetic transfer of LREE (except Ce) from sediment to interstitial water. At Site 795, the overall lack of correlation between Ce/Ce* and La{sub n}/Yb{sub n} suggests that other processes are occurring which mask the diagenetic behavior of all LREEs. First-order calculations of the Ce budget in Japan Sea waters and sediment indicate that {approximately}20% of the excess Ce adsorbed by settling particles is recycled within the water column, and that an additional {approximately}38% is recycled at or near the seafloor. Thus, because the remaining excess Ce is only {approximately}10% of the total Ce, there is not a large source of Ce to the deeply buried sediment, further suggesting that the downhole increase in Ce/Ce* is a passive response to diagenetic behavior of the other LREEs. The REE chemistry of Japan Sea sediment therefore predicts successive downhole addition of LREEs to deeply-buried interstitial waters.

• OSTI ID: 7278343
• Journal Information: Geochimica et Cosmochimica Acta; (United States), Vol. 55:9; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
54 ENVIRONMENTAL SCIENCES
RARE EARTHS
ECOLOGICAL CONCENTRATION
SEAWATER
CHEMICAL COMPOSITION
SEDIMENTS
DIAGENESIS
GEOCHEMISTRY
JAPAN
LITHOLOGY
OFFSHORE SITES
QUANTITY RATIO
SEAS
VARIATIONS
ASIA
CHEMISTRY
DEVELOPED COUNTRIES
ELEMENTS
HYDROGEN COMPOUNDS
METALS
OXYGEN COMPOUNDS
SURFACE WATERS
WATER
580000* - Geosciences
540350 - Environment
Aquatic- Site Resource & Use Studies- (1990-)