Chemical composition of manganese micronodules from expedition VA-05/1 in the Pacific Ocean
Cobertura |
MEDIAN LATITUDE: 10.068507 * MEDIAN LONGITUDE: -147.764000 * SOUTH-BOUND LATITUDE: 7.950000 * WEST-BOUND LONGITUDE: -152.500000 * NORTH-BOUND LATITUDE: 11.100000 * EAST-BOUND LONGITUDE: -146.300000 * DATE/TIME START: 1973-04-01T00:00:00 * DATE/TIME END: 1973-04-01T00:00:00 |
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Data(s) |
07/10/1974
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Resumo |
A radioisotope energy-dispersive X-ray (EDX) system has been used on board the German research vessel "Valdivia" during an exploration expedition in the northern equatorial Pacific in 1973. The instrumentation used consisted of an X-ray detection system incorporating a 30 mm2 effective-area Si (Li) detector with a measured energy resolution of 195 eV for Mn K alpha X-rays, standard nuclear electronics, a 1024-channel analyser and a data read-out unit. The X-ray spectra in the manganese-nodule samples were excited by a 30-mCi 238Pu source. The six elements Mn, Fe, Co, Ni, Cu and Zn were analysed on board. Precision values for the analyses were less than 3% for Mn, Fe, Ni, Cu and Zn and about 5% for Co. A total amount of 350 analyses was carried out during a one-month cruise. Average contents of 190 analysed whole manganese-nodule samples from all the sampling sites of the covered area were 23.3% Mn, 6.7% Fe, 0.23% Co, 1.16% Ni, 0.94% Cu and 0.10% Zn. The average content of the base metals expressed as the sum of the Co, Ni, Cu and Zn contents was 2.48%. A linear relationship between Mn and Ni in all analysed samples, including whole manganese-nodule samples, zones of manganese nodules and manganese crusts, was observed. The Mn/Ni ratio calculated by regression analysis was 23.0. Zonal variations of the chemical contents of the six elements in the manganese nodules were found. A size classification of the manganese nodules has been suggested. Geochemical correlations of Cu and Ni versus Mn/Fe in the investigated samples are given. |
Formato |
application/zip, 3 datasets |
Identificador | |
Idioma(s) |
en |
Publicador |
PANGAEA |
Relação |
Grant, J Bruce; Moore, Carla J; Alameddin, George; Chen, Kuiying; Barton, Mark (1992): The NOAA and MMS Marine Minerals Geochemical Database. National Geophysical Data Center, NOAA, doi:10.7289/V52Z13FT Fig. 4. Macrophoto of one half of an unpolished manganese nodule with a small nucleus and distinct concentric zones. (Location 9, expedition VA-05/1) (URI: hdl:10013/epic.48675.d001) Fig. 5. Manganese-iron-rich crust growing on altered andesitic rock material. (Location 12, dredge DK20, station 51, expedition VA-05/1) (URI: hdl:10013/epic.48675.d002) Warnken, Robin R; Virden, William T; Moore, Carla J (1992): The NOAA and MMS Marine Minerals Bibliography. National Geophysical Data Center, NOAA, doi:10.7289/V53X84KN |
Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
Fonte |
Supplement to: Friedrich, Günther; Kunzendorf, Helmar; Plüger, WL (1974): Ship-borne geochemical investigations of deep-sea manganese-nodule deposits in the Pacific using a radioisotope energy-dispersive X-ray system. Journal of Geochemical Exploration, 3(4), 303-317, doi:10.1016/0375-6742(74)90001-6 |
Palavras-Chave | #Atomic absorption spectrometry (AAS); Ca; Calcium; Clast shape; Co; Cobalt; Copper; Cu; Deposit type; Depth; DEPTH, sediment/rock; Description; Energy dispersive analysis of x-rays, EDAX; Event; Fe; Iron; Lead; Manganese; Mn; Ni; Nickel; NOAA and MMS Marine Minerals Geochemical Database; NOAA-MMS; Pb; Sample ID; Shape; Si; Silicon; X-ray microprobe; Zinc; Zn |
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Dataset |