Element mobility fluid controlled

Element mobility Element mobility describes the chemical changes which take place in rock after its formation, usually through interaction with a fluid. Most commonly, element mobility will take place during weathering, diagenesis and metamorphism or through interaction with a hydrothermal fluid. In metamorphic rocks, element mobility may also take place as a result of solid-state diffusion and melt generation. Here, however, we are chiefly concerned with fluid-controlled element mobility on... 

Sr, Eu) with the less mobile HFS elerhehts (Y, Hf, Zr, Ti, Nb, Ta). On the one hand the LIL element concentrations may be a function of the behaviour of a fluid phase, whilst the HFS element concentrations are controlled by the chemistry of the source and the crystal/melr processes which have taken place during the evolution of the rock. Partition coefficients for the HFS elements in the major rock-forming minerals in a range of melt compositions are summarized in Tables 4.1 to 4.3. 

To connect the two markedly different scenarios observed in the static and the well-mixed environments, it is natural to analyze the role of increasing mobility (Reichenbach et al., 2007). Karolyi et al. (2005) studied the above competition model combined with dispersion by a chaotic map that represents advection of fluid elements in the alternating sine-flow. By continuously changing the frequency of the chaotic dispersion as a control parameter, it is possible to follow the transitions between the two limiting situations. When the chaotic mixing is much faster than the local population dynamics, the killer and resistant cells gradually disappear from the population and only the sensitive cells survive. This is because the killer cells... 

The ingress and expulsion of water during metamorphism, chiefly as a consequence of hydration and dehydration reacdons, may give rise to changes in the chemical composidon of the parent rock as a consequence of pardcular elements becoming mobile in the fluid. These processes are controlled by the composidon of the fluid phase, its temperature and the rado of metamorphic fluid to the host rock. 

More mobile LIL element concentrations may be controlled by aqueous fluids but these elements are concentrated in the continental crust and can also be used as an indicator of crustal contamination of magmas. 

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