Chemical and isotopic compositions of authigenic carbonates from bottom sediments of Northwest Pacific marginal seas
Cobertura |
MEDIAN LATITUDE: 25.031643 * MEDIAN LONGITUDE: 122.056889 * SOUTH-BOUND LATITUDE: 8.943333 * WEST-BOUND LONGITUDE: 108.513300 * NORTH-BOUND LATITUDE: 54.576000 * EAST-BOUND LONGITUDE: 155.305500 * DATE/TIME START: 1993-01-01T00:00:00 * DATE/TIME END: 1996-09-17T00:00:00 |
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Data(s) |
03/02/1999
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Resumo |
The paper presents data on authigenic carbonate distribution in Holocene - Upper Pleistocene deposits of the Okhotsk, Japan, East China, Philippine and South China Seas. Description of carbonate samples, their chemical and isotope compositions are given. Chemical analysis of the samples indicates that almost all authigenic carbonates are composed of calcite or magnesian calcite; and only in one case, of siderite. Oxygen isotopic composition (d18O) ranges from +37.7 to +26.1 per mil (SMOW); it is, probably, connected with different temperatures of carbonate formation. A distinct geographic regularity is traced. Decrease in d18O values is observed from the cold Okhotsk Sea to the warm South China Sea. A very wide range of carbon isotopic composition (d13C from -42 to +3.8 per mil) indicates different sources of carbonic acid required for formation of these carbonates. As a basis for carbon isotopic composition we can distinguish three sources of carbonic acid in the studied sediments: microbiological methane oxidation, organic matter destruction during sediment diagenesis, and dissolved organogenic limestone. Thus, formation of authigenic carbonates in sediments from the marginal seas of the Northwest Pacific results from: 1) sediment diagenesis, 2) methane oxidation in zones of gas anomalies, 3) their precipitation from the supersaturated by carbonates sea shoal waters of tropical sea lagoons. |
Formato |
application/zip, 3 datasets |
Identificador |
https://doi.pangaea.de/10.1594/PANGAEA.775328 doi:10.1594/PANGAEA.775328 |
Idioma(s) |
en |
Publicador |
PANGAEA |
Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
Fonte |
Pacific Oceanology Institute, Far East Branch of Russian Academy of Sciences Supplement to: Astakhova, NV; Sorochinskaya, AV (1999): Authigenic carbonates in Upper Pleistocene - Holocene deposits of marginal seas, Northwest Pacific. Tikhookeanskaya Geologiya (Pacific Geology), 18(1), 41-49 |
Palavras-Chave | #Akademik A Nesmeyanov; Akademik M.A. Lavrentyev; AN_1993; AN25-936; Archive of Ocean Data; ARCOD; AS-99-119; AS-99-3155; AS-99-89102; AS-99-8935; AS-99-8937; AS-99-E35; AS-99-T-03B; AS-99-T-21; Ast-82156; Ast-8785; Ast-E29; Atomic absorption spectrometry (AAS); BC; Box corer; Ca; Calcium; Calcium oxide; CaO; Carbon dioxide; CO2; Copper; Cu; d13C carb; d18O carb; delta 13C, carbonate; delta 18O, carbonate; Depth; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Depth bot; Depth top; Dredge; DRG; Epoch; Event; Fe; FeO; GC; Gravity corer; Gravity corer (Kiel type); host sediments; Insol res; Insoluble residue; Iron; Iron oxide, FeO; LV27/GREGORY; LV27-1-2; LV27-1-3; LV27-1A; LV27-2-3; Magnesium; Magnesium oxide; Manganese; Manganese oxide; Mass spectrometry; Mg; MgO; Microprobe; Mn; MnO; MUC; MULT; MultiCorer; Multiple investigations; Nesmeyanov-93_9312; Obzh-89228; Okhotsk Sea; P31-3161; Sea of Okhotsk; SL; South China Sea; Zinc; Zn |
Tipo |
Dataset |