INVESTIGADORES
BJERG Ernesto Alfredo
congresos y reuniones científicas
Título:
Mantle xenoliths from Patagonia:petrography, geochemistry and geothermobarometry.
Autor/es:
BJERG, E A; NTAFLOS, TH; KURAT, G; LABUDIA, C; FERRACUTTI, G
Lugar:
Calafate
Reunión:
Congreso; XV Congreso Geológico Argentino; 2002
Resumen:
The hills of La Huerta and Valle Fertil, wich belong to the Western
Pampean Ranges in the Province of San Juan, NW Argentina, mainly consist of
metagabboic to metadioritic rocks that intruded the Proterozoic basement in the
Early Middle Ordovician (Famat
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In South
America, Patagonia offers an outstanding opportunity to gather information about
the present situation in the upper mantle at this latitude. This can be
achieved through the study of the young basaltic volcanism and the upper mantle
xenoliths that they brought to the surface. In the few past years Stern et al. (1986,1990); Labudia et al. (1984); Varela
et al. (1997); Barbieri (1998); Kilian et al. (1998); Ntaflos et al. (1998,1999,
2000,2001); Barbieri et al. (1999); Laurora et al. (2001); Bjerg et al. (1991 , 1994,1999,2000) and Gorring
and Kay (2001) have contributed with new data to a better knowledge of the
nature of the lithospheric mantle beneath Patagonia. Mantle xenoliths occurring
in alkali basaltic lavas (with OIB signature) and cinder cones are present in
three Patagonian morphostructural units, which from North to South are Comarca
Nordpatagonica, Chubut Extraandino and Patagonia Austral Extraandina. A
representative suite of mantle xenoliths were collected in the region between
latitudes 40° to 52° S and longitudes 6r to 71 ° W. The most representative
outcrops occur in the areas of Rio Negro, Chubut and Santa Cruz provinces.
