Element mobility

Element mobility Any suite of rocks which has been subjected to hydrothermal alteration or metamorphism is likely to suffer element mobility. It is essential, therefore, in any trace element study to demonstrate first that element concentrations are undisturbed and original before inferences can be made about the petrogenesis of the rock group. 

A special case of trace element mobilization is in the dehydration of subducted. ocean floor, a process thought to be pertinent to the generation of caIc-alkaU f magmas. Pearce (1983) has suggested that the elements Sr, K, Rb, Ba, Th, Ce, P -and Sm may. be mobile in such circumstances.,. . 

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Alderton, D.H.M., Pearce, J.A. and Potts, J. (1980) Rare earth element mobility during granite alteration evidence from southwest England. Earth Planet. Sci. Lett., 49, 149-165. 

Menzies, M., Seyfried, W. and Blanchard, D. (1979) Experimental evidence of rare earth element mobility in green-stones. Nature (London), 282, 398-399. 

Whitford, D.J., Korsch, M.J., Orritt, PM. and Craven, S.J. (1988) Rare-earth element mobility around the volcanogenic polymetallic massive sulfide deposit at Que River, Tasmania, Australia. Chem. Geol, 8, 105-112,... 

Smellie JAT, Stuckless JS (1985) Element mobility studies of two drill-cores from the Gotemar granite (Krakemala test site), southeast Sweden. Chem Geol 51 55-78 Smellie JAT, Karlsson F, Alexander WR (1997) Natural analogue studies present status and performance assessment implications. J Contam Hydrol 26 3-17... 

Kurz A, Derry LA, Chadwick OA, Alfano MJ (2000) Refractory element mobility in volcanic soils. Geology 28 683-686... 

Geologic Considerations Element mobility begins with the rock, mineral, and processed mineral materials. Source rocks and host rocks can have a... 

The geology not only provides the chemical source for trace-element mobility but it also provides the physical framework for water-flow paths. The structural properties of the rocks, the porosity, permeable fractures, provide for water-mineral reaction and element mobility. The geomorphology contributes to water-table levels, aquifer permeability, surface-water travel times, and time periods for erosion and sediment transport. Examples of... 

This contribution summarizes state-of-the-science with respect to USGS research on the hydrogeochemistry of trace-element mobilization and attenuation from mineralized areas during transport in surface and ground waters. The primary aspects are ... 

Kronberg, B. I., W. S. Fyfe, O. H. Leonardos Jr., and A. M. Santos (1979), "The Chemistry of Some Brazilian Soils Element Mobility during Intense Weathering", Chem. Geol. 24,11-229. 

Both the Na and K intensities in the K-feldspar profile of Figure 4 are stable with depth indicating a previously documented lack of alkali mobility in the surface layers of feldspars at low temperature (7). In contrast, K increases and Na decreases with depth beneath the obsidian surface demonstrating substantial elemental mobility. The K loss near the surface corresponds to a concentration increase measured in aqueous solution. Sodium profiles in obsidian should exhibit even greater near-surface losses relative to K based on profiles measured by HF leaching (3) and sputter-induced optical emission studies (6). 

Fayek, M. Kyser, T.K. 1997. Characterization of multiple fluid-flow events and rare-earth-element mobility associated with formation of unconformity-type uranium deposits in the Athabasca Basin, Saskatchewan. Canadian Mineralogist, 35, 627-658. 

Gerritse RG, Vriesema R, Dalenberg J, et al. 1982. Effect of sewage sludge on trace element mobility in soils. Journal of Environmental Quality 7 359-364. 

Saether (1980), Saether Runnells (1980), and Stollenwerk Runnells (1981) studied the leaching of various retorting residues from US Green River oil shales. Alkaline pH values were established even before 25% of the first pore-volume had passed through the waste, and were maintained at high levels for the first 15 pore-volumes. The main potentially toxic elements mobilized under such alkaline conditions were found to be As, B, F, Mo, and Se. In contrast, base metals such as Cu, Ni, Pb, and Zn will be immobilized under such alkaline conditions (Baes Mesmer 1976 Bell 1976). 

La Force, M.J., Fendorf, S.E., Li, G.C. et al. (1998) A laboratory evaluation of trace element mobility from flooding and nutrient loading of Coeur d Alene River sediments. Journal of Environmental Quality, 27(2), 318-28. 

In addition to the mobilization of these four elements, mobilization of aluminium and radionuclides originating from the nuclear fission process is also of concern under this classification. 

For industrially contaminated land, however, the contents extracted by the extractants in wide use are, in general, poorly correlated with plant uptake, growth or health but are predictors only of element mobility or potential mobility and hence can, at least potentially, be related to plant uptake in some environmental... 

Krasnodybska-Ostryga, B., M. Kaczorowska, and J. Golimowski. 2006. Use of ultrasound-assisted extraction for the evaluation of element mobility in bottom sediment collected at mining and smelting Pb-Zn ores area in Poland. Microchim. Acta 05-907 1-5. 

Mass Balance Considerations. The values of ER for the Fischer assay spent shale are contained in Table V. If it is assumed that the relative standard deviation in the analyses is 10%, then the relative probable error in ER would be 14% if the analytical errors were indeterminant and 20% if the errors were determinant (38). The mass ratio of OS-l/FS is 1.24 as derived from the assay data in Table I. It is not possible to conclude that any trace elements are mobilized from the solid material during the assay retorting. The ER results obtained for arsenic, selenium, and molybdenum indicate the importance of analytical precision in detecting any trace element mobilization during oil shale retorting. The values of RI contained in Table V show a similar dependence on analytical precision. The probable errors in these values are also between 14 and 20% if the relative standard deviation in the analytical results is assumed to be 10%. These results indicate that, within experimental error, none of the trace elements have been lost during Fischer assay. More definitive conclusions on whether elements are mobilized or lost can only be reached with more precise analytical... 

Pan Y. and Fleet M. E. (1996) Rare earth element mobility during prograde granulite facies metamorphism significance of fluorine. Petrol 123, 251-262. 

Table 1 Elemental mobility (kmolm ) and total % change in the Panola regolith. Negative values indicate element increases.

WHOLE-ROCK ELEMENTAL DATA AND LARGER-SCALE ELEMENTAL MOBILITY... 

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