Hydrous metasomatism and melt percolation in the lithospsheric mantle wedge underneath Comallo, Rio Negro Province, Argentina

PAPADOPOULOU, M.; NTAFLOS, TH.; BJERG, E. A.; GREGOIRE, M.

Viena

Conferencia; 11th EGU General Assembly; 2014

European Union of Geosciences

At Comallo, N. Patagonia, xenoliths are depleted sp-lherzolites, sp-harzburgites, wehrlites and clinopyroxenites. The studied samples are fine-grained with a dominant well-equilibrated equigranular texture whereas protogranular and porphyroclastic textures are rare. The rock forming minerals are olivine, ortho- and clinopyroxene and spinel. Relictic amphibole and phlogopite are present as well. The amphibole, where present, has been destabilized and shows breakdown reaction at the margin, forming second generation of ol, cpx and sp. The presence of disseminated amphibole and phlogopite, indicates that the lithospheric mantle underneath Comallo, has experienced limited modal metasomatism.