Results 141 to 150 of about 1,157 (196)

Composition of Pacific Ocean ferromanganese nodules

Marine Geology, 1977
Abstract Bulk composition of ferromanganese nodules from the pelagic environment of the Pacific Ocean is apparently related to nodule-growth rate, sediment-accumulation rate, and biologic productivity in the overlying seawater. Nodules with a high Mn Fe ratio and high Ni and Cu concentrations tend to occur in areas where primary productivity ...
David Z. Piper, Michael E. Williamson
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Magnetic order in freshwater ferromanganese nodules

Physica B+C, 1977
Abstract A set of eight ferromanganese concretations whose crystallinity deteriorates with increasing manganese content all order magnetically well above 4.2 K. The series presents a continous evolution from antiferromagnetic order in the iron-rich members, composed essentially of cristalline goethite, to speromagnetic order in the manganese-rich ...
J.M.D. Coey, D.W. Schindler
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Mössbauer study of Carpathian ferromanganese nodules

Hyperfine Interactions, 1986
Ferromanganese nodules from Flysh deposits of West Carpathian Mountains were studied by Mossbauer spectroscopy method. The presence of small-grain goethite and hematite was established and grain sizes roughly estimated.
J. Kraczka, A. Z. Hrynkiewicz, T. Wieser
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Buried ferromanganese nodules of the Magellan Seamounts

Lithology and Mineral Resources, 2016
Buried ferromanganese nodules and their stratiform accumulations (nodule horizons), which are widespread in sedimentary sequences of the Magellan Seamounts, have been studied in core obtained by shallow drilling on its guyots in the course of expeditions of the R/V Gelendzhik in 2001–2010.
M. E. Mel’nikov, V. V. Avdonin, S. P. Pletnev, T. E. Sedysheva   +3 more
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3He/4He ratios of marine ferromanganese nodules

Nature, 1985
Helium isotope ratios in the Earth's materials provide useful information about their mechanism of formation. Although more than 1,000 measurements have been reported, most are for land areas, and little is known about helium ratios on the ocean floor.
Yuji Sano, Kazuhiro Toyoda, Hiroshi Wakita   +2 more
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Large phillipsite crystal as ferromanganese nodule nucleus

Geo-Marine Letters, 1995
We report here the occurrence of, to date, the largest (21 × 10 × 8 mm) phillipsite crystal forming the nucleus of a diagenetically formed ferromanganese nodule from the Central Indian Ocean Basin (CIOB). Assuming an average rate of ferromanganese nodule accretion as ~ 2 mm/Ma and that of phillipsite growth as ~ 0.65 mm/Ka, the nucleus material appears
Ghosh, A.K., Mukhopadhyay, R.
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Magnetism and magnetic reversals in ferromanganese nodules

Earth and Planetary Science Letters, 1973
We have studied the strength, stability and direction of natural remanent magnetization of 25 deep-sea, JOIDES, shallow marine and fresh-water ferromanganese nodules. The nodules contain a reasonably stable and isotropic NRM of about the same magnitude as deep-sea sediments.
E.A. Crecelius, Roy Carpenter, R.T. Merrill   +2 more
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Sorption of Iron(II) on Ferromanganese Nodules

Russian Journal of Applied Chemistry, 2005
The dynamic capacity, specific surface area, grindability, and wearability of filter materials based on pyrolusite were determined. The dynamic capacity of ferromanganese nodules was compared with the capacity of imported filter materials.
D. E. Chirkst, O. V. Cheremisina, M. V. Ivanov, A. A. Chistyakov   +3 more
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Minor Element Composition of Ferromanganese Nodules

Science, 1967
Mineralogical and chemical analyses performed on 67 ferromanganese nodules from widely varying locations and depths within the marine environment indicate that the minor element composition is controlled by the mineralogy, and that the formation of the mineral phases is depth dependent.
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Cosmic dust in modern ferromanganese nodules

Solar System Research, 2017
This work is about the identification of modern cosmic dust that had survived heating during its high-velocity passage through the Earth’s atmosphere from 3He isotope concentrations in marine (Gulf of Finland) ferromanganese nodules (FMNs). The measured bulk composition of helium includes components of various origins, enabling the determination of the
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