Syenite pegmatitic segregation veins from La Peña alkaline complex, Mendoza, Argentina

PAGANO GÉNERO D. S.; GALLISKI M. A.; MÁRQUEZ ZAVALÍA M. F.; SKODA R.; NOVÁK M.

Ksiaz

Simposio; 7th International Symposium on Granitic Pegmatites; 2015

Uniwersytet Slaski

Veins with pegmatite textures areuncommon in basic alkaline magmas crystallized at low pressures, although someoccurrences have been described (Galliski et al. 2004 and references therein).These authors indicated that development of the pegmatite textures in ijolitepegmatites at La Madera, Córdoba, Argentina, was initiated by enrichment of themelt in flux components (PO43-, CO32-, H2O) that inhibited nucleation and favored an increasingrate of crystal growth at high cooling rates. The syenite pegmatiticsegregation veins (SPSV) of La Peña alkaline complex (LPC), initially describedby Zappettini et al. (2013), represent an opportunity to explore the origin ofthese segregations in alkaline basic magmas. In this contribution we detail thepetrography and show a few preliminary results of chemical variations ofminerals obtained by EPMA, used for understanding the genesis of these specificdifferentiates.