Dynamic geochemistry

Ribe NM (1988) Dynamical geochemistry of the Hawaiian plume. Earth Planet Sci Lett 88 37-46 Ribe NM G996) The dynamics of plume-ridge interaction 2. Off-ridge plumes. J Geophys Res 101 16195-16204... 

During the initial stages of electric potential application, the soil pH changes spatially and temporally, which leads to dynamic geochemistry, leading to mass transfer from one form (phase) to the other (soUd/precipitated, sorbed, dissolved, and free phases) and changes in chemical speciation.The most important geochemical reactions that must be considered include... 

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... 

The variety of life forms to be found near hydrothermal vents does not, of course, mean that life itself originated there these geological systems are much too unstable for that. The dynamics of tectonic plates cause the vents to disappear after some decades, or at most after a few hundred years. According to Nils Holm from the Department of Geology and Geochemistry at the University of Stockholm, the discovery of the hydrothermal vents led to intense, and in some cases controversial, discussions of the question as to whether hydrothermal systems were the birthplaces of life around four billion years ago. Many geologists believe that hydrothermal activity on the primeval Earth was probably stronger than it is today, as the thick... 

Ben Othman D, Luck JM, Toumoud MG (1997) Geochemistry and water dynamics application to short time-scale flood phenomena in a small Mediterranean catchment. I- Alkalis, alkali-earths and Sr isotopes. Chem Geol 140 9-28... 

Tardy Y, Bustillo V, Boeglin JL (2004) Geochemistry applied to the watershed survey hydrograph separation, erosion and soil dynamics. A case study the basin of the Niger River, Africa. Appl Geochem 19 469-518... 

In this chapter, we consider how to construct quantitative models of the dynamics of microbial communities, building on our discussion of microbial kinetics in Chapter 18. In our modeling, we take care to account for how the ambient geochemistry controls microbial growth, and the effect of the growth on geochemical conditions. 

The potential for the employment of plasma emission spectrometry is enormous and it is finding use in almost every field where trace element analysis is carried out. Some seventy elements, including most metals and some non-metals, such as phosphorus and carbon, may be determined individually or in parallel. As many as thirty or more elements may be determined on the same sample. Table 8.4 is illustrative of elements which may be analysed and compares detection limits for plasma emission with those for ICP-MS and atomic absorption. Rocks, soils, waters and biological tissue are typical of samples to which the method may be applied. In geochemistry, and in quality control of potable waters and pollution studies in general, the multi-element capability and wide (105) dynamic range of the method are of great value. Plasma emission spectrometry is well established as a routine method of analysis in these areas. 

Wakeham, S.G., and E.A. Canuel. 1988. Organic geochemistry of particulate matter in the eastern tropical North Pacific Ocean Implications for particle dynamics. Journal of Marine Research 46 183-213. 

O Day PA (1999) Molecular environmental geochemistry. Rev Geophy 37 249-274 Paul FA, Clark FE (1989) Soil microbiology and biochemistry. Academic Press, New York Pignatello JJ (1989) Sorption dynamics of organic compounds in soils and sediments. In Sawhney BL and Brown K (eds) Reactions and movement of organic chemicals in soils. Soil Science Society of America, Madison, Wl, pp 45-80... 

Kubicki, J.D. and Lasaga, A.C., Molecular dynamics and diffusion in silicate melts, in Diffusion, Atomic Ordering, and Mass Transport Selected Problems in Geochemistry, Ganguly, J., Ed., Springer-Verlag, New York, 1991, P- L... 

An important development stemming from heterogeneous accretion models is that they introduced the concept that the Earth was built from more than one component and that these may have been accreted in separate stages. This provided an apparent answer to the problem of how to build a planet with a reduced metallic core and an oxidized sihcate mantle. However, heterogeneous accretion is hard to reconcile with modem models for the protracted dynamics of terrestrial planet accretion compared with the shortness of nebular timescales. Therefore, they have been abandoned by most scientists and are barely mentioned in modem geochemistry literature any more. 

The major aim of mantle geochemistry has been, from the beginning, to elucidate the structure and evolution of the Earth s interior, and it was clear that this can only be done in concert with observations and ideas derived from conventional field geology and from geophysics. The discussion here will concentrate on the chemical structure of the recent mantle, because the early mantle evolution and dynamics and history of convective mixing are treated in Chapters 2.12 and 2.13. 

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