Metasomatic infiltration

Modeling of the whole-rock and mineral trace-element compositions in xenoliths that have experienced metasomatic infiltration of melts led Ionov et al. (2002a) to conclude that the REE and HFSE element compositions of peridotites adjacent to veins bear the chemical fingerprints of the metasomatic agent closest to its source (e.g., a melt vein). Further away, signatures are increasingly dominated by fractionation processes related to melt percolation. 

Guy, B. (1984). Contribution to the theory of infiltration metasomatic zoning the formation of sharp fronts a geometrical model. Bull. Mineral., 107, 93-105. 

As it provides easy access to a variety of metasomatized mantle rocks, the Lherz massif has been recently the focus of detailed geochemical studies—as well as the source of debates—concerning melt infiltration and melt-rock interaction processes in wall rocks of... 

In addition, a detailed study of a metasomatized wall rock adjacent to an amphi-bole-pyroxenite dike has revealed that the contamination in " Nd/ " " Nd and Sr/ Sr is spatially limited to a distance of <25 cm from the dike (Bodinier et al., 2003). This distance is interpreted as the chromatographic front of neodymium and strontium since the infiltration of small volume melts probably occurred on a greater distance in the host peridotite, as attested by the enrichment of the highly incompatible elements observed at 25-80 cm from the dike (e.g., lanthanum and cerium, see Section... 

Zanetti A., Vannucci R., Bottazzi P., Oberti R., and Ottolini L. (1996) Infiltration metasomatism at Lherz as monitored by systematic ion-microprobe investigations close to a horn-blendite vein. In Melt Processes and Exhumation Garnet, Spinel and Plagioclase Facies Mantle (eds. M. A. Menzies, J. L. Bodinier, F. Frey, F. Gervilla, and P. Kelemen). Elsevier, Amsterdam, Netherlands, vol. 134, pp. 113—133. 

Major element mass transfer can be coupled to isotopic shifts that allow the fluid source to be traced. Tracy et al. (1983) found extreme metasomatism, including the loss of nearly all potassium and sodium, for metacarbonate rock adjacent to a quartz vein in the Wepawaug Schist. The infiltrating fluid had lower Xqo than fluid... 

Fletcher R. C. and Hofmann A. W. (1973) Simple models of diffusion and combined diffusion-infiltration metasomatism. 

Guy, B. (1993). Mathematical revision of Korzhinskii s theory of infiltration metasomatic zoning. European Journal of Mineralogy, 5, 317 339. 

Hofmann, A. (1972). Chromatographic theory of infiltration metasomatism and its application to feldspars. American Journal of Science, 111, 69-90. 

Direct evidence for metasomatism is derived from petrochemical studies of mantle nodules. Lloyd and Bailey reported on ultramafic nodules from the West Eifel and Southwest Uganda volcanic provinces, and described a series of primary (i.e. unaffected by low-pressure environment) features that include pockets or veins of hydrated minerals (amphibole, mica) or, sometimes, vesicular glass. Based on the textures and on the chemical sequence of the metasomatized nodules they concluded that the mantle portion represented by the nodules was subjected to extensive infiltration of elements, such as K, Na, Fe, Rb, etc. Metasomatic enrichment of mantle rocks was also reported by Boettcher era/.," Erlank era/., Sutherland and Hollis " and many others (see Table 3 in Menzies and Murthy and Menzies ). 

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