INSTITUTO DE GEOCRONOLOGIA Y GEOLOGIA ISOTOPICA
Unidad Ejecutora - UE
congresos y reuniones científicas
. Geochemistry of the Yaminué metaigneous complex
LÓPEZ DE LUCHI, M. G.; RAPALINI, A.E.; MARTÍNEZ DOPICO, C.; RAPELA, C.W.; PANKHURST, B
Congreso; 19 Congreso Geológico Argentino; 2014
Asociación Geológica Argentina
The Yaminué MetaIgneous Complex (YIC) (Rapalini et al. 2013 and references therein which extends south of Ramos Mexía station (40º 30? 05??S-67º 15? 42??W) down to the Yaminué village (40º 57? 03?S?-67º 10? 27??W), is a 780 km2 sheeted orthogneissic complex. Foliated equigranular or porphyritic biotite- and scarce biotite-amphibole granitoids are interlayered with locally coarse grained foliated equigranular or porphyric biotite-muscovite leucogranite. Undeformed N to NNE trending leucogranitic dykes are present in the south. The host of the YIC is represented in the south by marble plus scarce amphibolites.For many years this unit was considered of Precambrian age based on low quality radimetric dating for rocks located in the central part (see López de Luchi et al. 2010 for details). Basei et al. (2002) calculated U-Pb conventional zircon ages of 305±31, 281± 29, 276±11 Ma and 244±14 Ma, for rocks located in the central and southern parts. New accurate SHRIMP dating allowed to recognize Ordovician ages for the southern sector (Rapalini et al. 2013), Permian-Late Permian for the granodiorite and tonalite of the central sector (Chernicoff et al. 2013, Pankhurst et al. 2014) and Early Triassic ages for the granodiorite of the northern sector (Tohver et al. in prep).