GARNETS FROM LA-PAVA-RAMADAS RHYOLITE (NW ARGENTINA) AND FROM ITS GRANITE XENOLITHS

Authors
GAUTHIER PJ DERUELLE B VIRAMONTE J APARICIO A
Citation
Pj. Gauthier et al., GARNETS FROM LA-PAVA-RAMADAS RHYOLITE (NW ARGENTINA) AND FROM ITS GRANITE XENOLITHS, Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre, 318(12), 1994, pp. 1629-1635
Citations number
24
Categorie Soggetti
Multidisciplinary Sciences
Journal title
Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre → ACNP
ISSN journal
07644450
Volume
318
Issue
12
Year of publication
1994
Part
2
Pages
1629 - 1635
Database
ISI
SICI code
0764-4450(1994)318:12<1629:GFLR(A>2.0.ZU;2-V
Abstract
La Pava-Ramadas caldera rhyolites (8.75 Ma), NW Argentina, contain pum ice and obsidian blocks and granite xenoliths. Euhedral garnet crystal s (< 1 mm) occur in all these lavas. The granite is also garnet-bearin g. Crystal faces from garnets in pumices appear to be concave on SEM. Garnets from lavas and garnets from granite are spessartine-rich (Spe2 4 and Spe33-38 respectively). Garnets of both groups crystallized from distinct non-cogenetic peraluminous Mn-rich magmas at shallow depth ( T < 950-degrees-C, P < 3 kb).