Marine sediments, geochemistry

Jorgensen, B. B. and Nelson, D.C, 2004. Sulfide oxidation in marine sediments Geochemistry meets microbiology. In Amend, J.P., Edwards, K.J. and Lyons, T.W. (eds). Sulfur Biogeochemistry - Past and Present. Geological Society of America, pp. 63-... 

Holser, W.T. and Kaplan, I.R. (1966) Isotope geochemistry of sedimentary sulfates. Chem. Geol., 1, 93-135. Huerta-Diaz and Morse, J.W. (1992) Pyritization of trace metals in anoxic marine sediments. Geochim. Cosmochim. Acta, 56, 2681-2702. 

The geochemistry of marine sediments is a major source of information about the past environment. Of the many measurements that provide such information, those of the U-series nuclides are unusual in that they inform us about the rate and timescales of processes. Oceanic processes such as sedimentation, productivity, and circulation, typically occur on timescales too short to be assessed using parent-daughter isotope systems such as Rb-Sr or Sm-Nd. So the only radioactive clocks that we can turn to are those provided by cosmogenic nuclides (principally or the U-series nuclides. This makes the U-series nuclides powerful allies in the quest to understand the past ocean-climate system and has led to their widespread application over the last decade. 

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... 

Ader M, Coleman ML, Doyle SP, Stroud M, Wakelin D (2001) Methods for the stable isotopic analysis of chlorine in chlorate and perchlorate compounds. Anal Chem 73(20) 4946-4950 Ben Othman D, White WM, Patchett J (1989) The geochemistry of marine sediments, island arc magma genesis, and crust-mantle recycling. Earth Planet Sci Lett 94 1-21 Beneteau KM, Aravena R, Frape SK (1999) Isotopic characterization of chlorinated solvents-laboratory and field results. Organic Geochemistry 30(8A) 739-753... 

Schematic diagram of the coupled iron and phosphate cycles during early diagenesis in marine sediments. Light gray ovals and circles represent solid phases black arrows are solid-phase fluxes. White outlined black arrows Indicate reactions white arrows are diffusion pathways. Source From Ruttenberg, K. C. (2003). Treatise on Geochemistry, Elsevier Ltd. pp. 585-643.

A conceptual model Illustrating the pathways by which sedimenting POM is transformed into molecularly uncharacterizable organic matter. Source-. From Burdige, D. J. (2006). Geochemistry of Marine Sediments. Princeton University Press. 

T1 isotope ratios might be also used as a tracer in mantle geochemistry (Nielsen et al. 2006 2007). Since most geochemical reservoirs except Fe-Mn marine sediments and low temperature seawater altered basalts are more or less invariant in T1 isotope composition, admixing af small amounts of either of these two components into the mantle should induce small T1 isotope fractionations in mantle derived rocks. And indeed, evidence for the presence of Fe-Mn sediments in the mantle underneath Hawaii was presented by Nielsen et al. (2006). 

PORRENGA (D.H.), 1967b. Clay mineralogy and geochemistry of recent marine sediments in tropical areas. Thesis. University of Amsterdam. 

Hedges, J. L, and Oades, J. M. (1997). Comparative organic geochemistries of soils and marine sediments. Org. Geochem. 27, 319-361. 

Brownwell, B.J., Farrington, J.W. (1985) Partitioning of PCBs in marine sediments. In Marine and Estuarine Geochemistry. Segleo, A.C., Hattori, A., Eds., Chapter 7, pp. 97-120. Lewis Publishers., Inc., Chelsea, Michigan. 

Natural carbonate minerals do not form from pure solutions where the only components are water, calcium, and the carbonic acid system species. Because of the general phenomenon known as coprecipitation, at least trace amounts of all components present in the solution from which a carbonate mineral forms can be incorporated into the solid. Natural carbonates contain such coprecipitates in concentrations ranging from trace (e.g., heavy metals), to minor (e.g., Sr), to major (e.g., Mg). When the concentration of the coprecipitate reaches major (>1%) concentrations, it can significantly alter the chemical properties of the carbonate mineral, such as its solubility. The most important example of this mineral property in marine sediments is the magnesian calcites, which commonly contain in excess of 12 mole % Mg. The fact that natural carbonate minerals contain coprecipitates whose concentrations reflect the composition of the solution and conditions, such as temperature, under which their formation took place, means that there is potentially a large amount of information which can be obtained from the study of carbonate mineral composition. This type of information allied with stable isotope ratio data, which are influenced by many of the same environmental factors, has become a major area of study in carbonate geochemistry. 

Volkman, J.K., Farrington, J.W., Gagosian, R.B., and Wakeham, S.G. (1983) Lipid composition of coastal marine sediments from the Peru upwelling region In Advances in Organic Geochemistry (Bjoroy, M., ed.), pp. 228-240, John Wiley, Chichester, UK. 

Hedges, J. I., and D. C. Mann. 1979. "The lignin geochemistry of marine sediments from the southern Washington coast." Geochimica Cosmochimica Acta 43 1809-1818. 

Ben Othman D., White W. M., and Patchett J. (1989) The geochemistry of marine sediments, island arc magma genesis, and crust-mantle recycling. Earth Planet. Set Utt. 94, 1-21. 

Calvert S. E. and Padersen T. F. (1993) Geochemistry of recent oxic and anoxic marine sediments imphcations for the geological record. Mar. Geol. 113, 67-88. 

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