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Optical and geochemical studies of granulometric fractions from recent marine sediments
1010
C. Chemical Oceanography
evolution ends at 300°C, above which temperature the organic matter undergoes general cracking. BRGM, Dept. GMX, bat. A2, BP 6009, 45060 Orleans Cedex, France. 85:7025 Duchaufour, H., L.J. Monrozier and R. Pelet, 1984. Optical and geochemical studies of 8ranulometric fractions from recent marine sediments. Org. Geochem., 6:305-315.
Biological aggregates were formed only in sediments from upweUing regions. Aggregation by organic colloidal structures was observed preferentially in marine autochthonous material. Amounts of humic compounds in the granulometric fractions ranged ~15% to >50% depending on the nature and abundance of ctay-humic complexes and oxygenation level. Elemental composition of humic acids in the fractions may vary or not, depending on the sedimentary processes involved; but it is noteworthy that humic compounds from particles (0.1 /~m exhibit a low degree of condensation. Centre de Pedol. biol., BP 5, 54501 Vandoeuvre Les Nancy Cedex, France. 85:7026 Goossens, H., R.S. Mirmaar and H. Verplanke, 1984. Carbon mineralization in the water of Lake Grevelingen (The Netherlands), as measured with the oxygen consumption method. Neth. J. Sea Res., 18(3-4):480-491.
The oxygen consumption rates (OCR) of water samples from an artificially enclosed estuary (Lake Grevelingen) were measured to assess the community C consumption without the inherent problems of tracer methodology. Carbon respiration was estimated at 305 g C m -2 a -1. Statistical analysis revealed a high correlation between OCR and the total solar irradiance for the five days prior to sampling that was not primarily a temperature effect. The discrepancy between C production and mineralization estimates is discussed. Delft Univ. of Tech., de Vries van Heystplantsoen 2, 2628 RZ Delft, Netherlands. (gsb) 85:7027 Hussler, G., J. Connan and P. Albrecht, 1984. Novel families
of
tetra-
and
ilexa~dt¢
arolaatt¢
hopanoids predominant in cerimmte rocks and crude oils. Org. Geochem., 6:39-49. Dept. de Chim, Univ. Louis Pasteur, 1 rue Blaise Pascal, 67008 Strasbourg, France. 85:7028 Jacobs, Lucinda, Steven Emerson and Jens Skei, 1985. Partitioning and transport of metals across
OLR (1985) 32 (12)
the OffH2S interface in a permanently anoxic ~: Framvaren Fjord, Norway. Geochim. cosmochim. Acta, 49(6): 1433-1444. Metal sulfide precipitation influences the magnitude of metal enrichment in the sediments. The transition metals, Mn, Fe, and Co, show active involvement in redox cycling, characterized by dissolved maxima just below the O2/H2S interface. Ni concentrations appear unaffected by processes influencing the profiles of the other metals. Cu, Zn, and Cd display a dramatic solubility decrease across the interface, are not involved in redox cycling, and are enriched in the sediments relative to a lithogenic component by factors of 11, 105, and 420, respectively. Ion activity products provide evidence that chemical equilibrium with a pure metal sulfide solid phase is not the dominant process controlling dissolved metal concentrations in the sulfide-containing waters. Univ. of Bern, Inst. for Inorganic, Analyt., and Phys. Chem., CH-3000 Bern 9, Freiestrasse 3, Switzerland. 85:7029 Kelderman, P., 1984. Sediment-water exchange in Lake Grevelingen under different envLronmental conditions. Neth. J. Sea Res., 18(3-4):286-311.
Under aerobic laboratory conditions, the influences of sediment type, water temperature, and (for phosphate only) overlying water phosphate concentration and water turbulence on the sediment-water exchange of silicate and phosphate were assessed for a saline lake. A strong temperature dependence was observed, with fluxes (mg compound m 2 d ~) of 5-+3.2 at 5°C to 85_+ 18 at 20°C for Si and 0.5-+0.7 at 5°C to I 1-+3.4 at 20°C for PO4-P. A phosphate concentration model is also presented. Intl. Inst. for Hydraulic and Environ. Engrg., P.O. Box 3015, 2601 DA Delft, Netherlands. (gsb) 85:7030 Klok, J., M. Baas, H.C. Cox, J.W. de Leeuw, W.I.C. Rijpstra and P.A. Sehenck, 1984. Qualitative and quantitative characterization of the total organic matter in a recent marine sediment (Part II), Org. Geochem, 6:265-278. Total organic matter of a recent marine diatomaceous ooze is studied by analysis of its water and acid extracts and residues. Extraction data reveal major contributions of carbohydrates (22%), 'volatiles' (12%) and proteins (11%) and a smaller contribution of lipids (4%) and volatile fatty acids (1%). The residual organic carbon (50%) mainly shows aliphatic characteristics. Among the compounds identified in the extracts, some with algal and bacterial origins are distinguishable. Delft Univ. of Tech., Dept. of Chem. and Chem. Engrg., De
C. Chemical Oceanography
evolution ends at 300°C, above which temperature the organic matter undergoes general cracking. BRGM, Dept. GMX, bat. A2, BP 6009, 45060 Orleans Cedex, France. 85:7025 Duchaufour, H., L.J. Monrozier and R. Pelet, 1984. Optical and geochemical studies of 8ranulometric fractions from recent marine sediments. Org. Geochem., 6:305-315.
Biological aggregates were formed only in sediments from upweUing regions. Aggregation by organic colloidal structures was observed preferentially in marine autochthonous material. Amounts of humic compounds in the granulometric fractions ranged ~15% to >50% depending on the nature and abundance of ctay-humic complexes and oxygenation level. Elemental composition of humic acids in the fractions may vary or not, depending on the sedimentary processes involved; but it is noteworthy that humic compounds from particles (0.1 /~m exhibit a low degree of condensation. Centre de Pedol. biol., BP 5, 54501 Vandoeuvre Les Nancy Cedex, France. 85:7026 Goossens, H., R.S. Mirmaar and H. Verplanke, 1984. Carbon mineralization in the water of Lake Grevelingen (The Netherlands), as measured with the oxygen consumption method. Neth. J. Sea Res., 18(3-4):480-491.
The oxygen consumption rates (OCR) of water samples from an artificially enclosed estuary (Lake Grevelingen) were measured to assess the community C consumption without the inherent problems of tracer methodology. Carbon respiration was estimated at 305 g C m -2 a -1. Statistical analysis revealed a high correlation between OCR and the total solar irradiance for the five days prior to sampling that was not primarily a temperature effect. The discrepancy between C production and mineralization estimates is discussed. Delft Univ. of Tech., de Vries van Heystplantsoen 2, 2628 RZ Delft, Netherlands. (gsb) 85:7027 Hussler, G., J. Connan and P. Albrecht, 1984. Novel families
of
tetra-
and
ilexa~dt¢
arolaatt¢
hopanoids predominant in cerimmte rocks and crude oils. Org. Geochem., 6:39-49. Dept. de Chim, Univ. Louis Pasteur, 1 rue Blaise Pascal, 67008 Strasbourg, France. 85:7028 Jacobs, Lucinda, Steven Emerson and Jens Skei, 1985. Partitioning and transport of metals across
OLR (1985) 32 (12)
the OffH2S interface in a permanently anoxic ~: Framvaren Fjord, Norway. Geochim. cosmochim. Acta, 49(6): 1433-1444. Metal sulfide precipitation influences the magnitude of metal enrichment in the sediments. The transition metals, Mn, Fe, and Co, show active involvement in redox cycling, characterized by dissolved maxima just below the O2/H2S interface. Ni concentrations appear unaffected by processes influencing the profiles of the other metals. Cu, Zn, and Cd display a dramatic solubility decrease across the interface, are not involved in redox cycling, and are enriched in the sediments relative to a lithogenic component by factors of 11, 105, and 420, respectively. Ion activity products provide evidence that chemical equilibrium with a pure metal sulfide solid phase is not the dominant process controlling dissolved metal concentrations in the sulfide-containing waters. Univ. of Bern, Inst. for Inorganic, Analyt., and Phys. Chem., CH-3000 Bern 9, Freiestrasse 3, Switzerland. 85:7029 Kelderman, P., 1984. Sediment-water exchange in Lake Grevelingen under different envLronmental conditions. Neth. J. Sea Res., 18(3-4):286-311.
Under aerobic laboratory conditions, the influences of sediment type, water temperature, and (for phosphate only) overlying water phosphate concentration and water turbulence on the sediment-water exchange of silicate and phosphate were assessed for a saline lake. A strong temperature dependence was observed, with fluxes (mg compound m 2 d ~) of 5-+3.2 at 5°C to 85_+ 18 at 20°C for Si and 0.5-+0.7 at 5°C to I 1-+3.4 at 20°C for PO4-P. A phosphate concentration model is also presented. Intl. Inst. for Hydraulic and Environ. Engrg., P.O. Box 3015, 2601 DA Delft, Netherlands. (gsb) 85:7030 Klok, J., M. Baas, H.C. Cox, J.W. de Leeuw, W.I.C. Rijpstra and P.A. Sehenck, 1984. Qualitative and quantitative characterization of the total organic matter in a recent marine sediment (Part II), Org. Geochem, 6:265-278. Total organic matter of a recent marine diatomaceous ooze is studied by analysis of its water and acid extracts and residues. Extraction data reveal major contributions of carbohydrates (22%), 'volatiles' (12%) and proteins (11%) and a smaller contribution of lipids (4%) and volatile fatty acids (1%). The residual organic carbon (50%) mainly shows aliphatic characteristics. Among the compounds identified in the extracts, some with algal and bacterial origins are distinguishable. Delft Univ. of Tech., Dept. of Chem. and Chem. Engrg., De