Oceans chemistry

The failure to identify the necessary authigenic silicate phases in sufficient quantities in marine sediments has led oceanographers to consider different approaches. The current models for seawater composition emphasize the dominant role played by the balance between the various inputs and outputs from the ocean. Mass balance calculations have become more important than solubility relationships in explaining oceanic chemistry. The difference between the equilibrium and mass balance points of view is not just a matter of mathematical and chemical formalism. In the equilibrium case, one would expect a very constant composition of the ocean and its sediments over geological time. In the other case, historical variations in the rates of input and removal should be reflected by changes in ocean composition and may be preserved in the sedimentary record. Models that emphasize the role of kinetic and material balance considerations are called kinetic models of seawater. This reasoning was pulled together by Broecker (1971) in a paper called "A kinetic model for the chemical composition of sea water."... 

Broecker, W. S. (1982). Ocean chemistry during glacial time. Geochim. Cosmochim. Acta 46,1689-1706. 

Clegg SL, Whitfield M (1993) Application of a generalized scavenging model to time series " Th and particle data during the JGQFS North Atlantic bloom experiment. Deep-Sea Res 40(8) 1529-1545 Cocluan JK (1992) The oceanic chemistry of the uranium and thorium series nuclides. In Uranium-series disequilibrium Applications to earth, marine, and enviromnental sciences. Ivanovich M, Harmon RS (eds) Qxford University Press, Qxford p 334-395... 

Cochran JK (1984) The fates of U and Th decay series nuclides in the estuarine environment. In The Estuary as a Filter. Kennedy VS (ed) Academic Press, London, p 179-220 Cochran JK (1992) The oceanic chemistry of the uranium - and thorium - series nuclides. In Uranium-series Disequilibrium Applications to Earth, Marine and Environmental Sciences. Ivanovich M, Harmon RS (eds) Clarendon Press, Oxford, p 334-395 Cochran JK, Masque P (2003) Short-lived U/Th-series radionuclides in the ocean tracers for scavenging rates, export fluxes and particle dynamics. Rev Mineral Geochem 52 461-492 Cochran JK, Carey AE, Sholkovitz ER, Surprenant LD (1986) The geochemistry of uranium and thorium in coastal marine-sediments and sediment pore waters. Geochim Cosmochim Acta 50 663-680 Corbett DR, Chanton J, Burnett W, Dillon K, Rutkowski C. (1999) Patterns of groundwater discharge into Florida Bay. Linrnol Oceanogr 44 1045-1055... 

Anbar, A.D. and Knoll, A.M. (2002). Proterozoic ocean chemistry and evolution a bioinorganic bridge. Science, 297, 1137-1142... 

Table 1.6. Precision of the procedure for Cu, Ni, Cd, Zn, Fe and Pb as applied in ocean chemistry clean room [38]...

Wong CS, Kremling K, Riley JP et al. (1985) Ocean Chemistry Division Institute of Ocean Sciences, PO Box 6000, Sidney, BC, V8L 4B2, Canada. Ocean Chemistry Division contract to SEAKEM Oceanography Ltd., Sidney, BC, Canada. Marine Chemistry Department, Institut fur Meereskunde und der Universitat, Kiel, Dunsternbrooker Weg 20, 2300 Kiel, FR Germany. Department of Oceanography, University of Liverpool, PO Box 147, Liverpool, L69 3BX, UK... 

The applications that I have considered so far have been limited to simple descriptions of aspects of ocean chemistry, but the powerful com-... 

Broecker, W. S., 1980, Glacial to Interglacial Changes in Ocean Chemistry, to be published in the CIMAS symposium volume. 

The recent Future of Ocean Chemistry in the U.S. (FOCUS) report (NSF, 2000) identified eight key themes for future chemical oceanographic research (Box 1.2). Clearly, oceanographic analyses over the coming decades will involve a wide variety of dissolved and particulate constituents from coastal ocean, open ocean, and seafloor settings, and thus a variety of reference materials will be required to represent these key sample matrices. 

Forecasting and characterization of anthropogenic changes in ocean chemistry. 

Druffel, E. R.M. 1995. Geochemistry of corals Proxies of past ocean chemistry, ocean circulation and climate. National Academy of Sciences Colloquium on Carbon Dioxide and Climate Change. 

National Science Foundation. 2000. Future of Ocean Chemistry in the U.S. (FOCUS). Arlington, Virginia National Science Foundation. 

Canfield DE (1998) Anew model for Proterozoic ocean chemistry. Nature 396 450-453 Canfield DE, Lyons TW, Raiswell R (1996) A model for iron deposition to euxinic Black Sea sediments. Am JSci 296 818-834... 

Schauble EA, Rossman GR, Taylor HP (2001) Theoretical estimates of equilibrium Fe-isotope fractionations from vibrational spectroscopy. Geochim Cosmochim Acta 65 2487-2597 Shen Y, Canfield DE, Knoll AH (2002) Middle Proterozoic ocean chemistry Evidence from the McArthur Basin, northern Australia. Am J Sci 302 81-109... 

The global distribution of continental shelves, including their widths, has fluctuated over geologic time in response to (1) tectonism that changes the shape and elevation of the crustal plates, (2) isostatic readjustments in the elevation of land masses, and (3) climate shifts that alter the volume of the ocean. Changes in the extent and width of the shelves have affected the magnitude of various sedimentary sinks over time, with significant impacts on ocean chemistry. This topic is discussed further in Chapter 21. 

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