Vougioukalakis, "Inverse differentiation pathway by multiple mafic magma
refilling in the last magmatic activity of Nisyros Volcano, Greece," Bulletin of Volcanology, vol.
Unfractionated HREE (and Y) patterns generally suggest that the mafic magma
was possibly produced outside the garnet stability field (i.e.
and Brewer, T.S.: 2000, Remobilisation of andesitic magma by intrusion of mafic magma
at the Soufriere Hills volcano, Montserrat, West Indies.
Experimental and observational evidence suggest that olivine, followed by clinopyroxene and plagioclase, are the earliest crystallizing phases from mafic magma
. Fractional crystallization of ferromagnesian phases such as olivine and clinopyroxene leads to systematic depletion in Fe[O.sup.*], MgO, and enrichment in elements such as Si[O.sub.2], [Na.sub.2]O and [K.sub.2]O.
A late influx of mafic magma
disrupted older mafic rocks and hybridised with granite, producing complex, heterogeneous "diorite".
Underplating of the crust by mafic magma
can lead to partial melting and production of felsic magma.
(2000) suggested that, if ponding mafic magma
operates like a rising piston, co-mingled lavas are slowly expulsed reaching the surface by a volatile-poor and non-explosive effusive eruption.
Water lowers the temperatures that are required for the partial melting in the mantle wedge, which produces mafic magma
, and in the crust, produces felsic magma.
A likely model is that a mafic magma
(possibly mantle derived) of the MPS was emplaced first and underwent substantial crystal fractionation to produce the mafic and ultramafic St.
Are these youngest granites a result of partial melting of the country rocks by the rising mafic magma
or did the waning phases of the granite magmatism overlapped with mafic magmatism?
Hybrids dominated by the crustal melts are expressed by the various facies of the Monte Capanne pluton, whereas the mafic magma
hybrids are represented by the ubiquitous presence of a wide variety of mafic microgranular enclaves.
In these "fossil", high-level magma chambers, such as the Pleasant Bay Complex (Wiebe 1993a), field relations indicate that mafic magma
was episodically injected into the crystallizing felsic magma chamber.