PETROLOGÍA DEL ENJAMBRE DE DIQUES MÁFICOS INTRUÍDOS EN EL GRANITO ÑUÑORCO EN LA ZONA DE LA CUESTA DE MIRANDA, SISTEMA DE FAMATINA, LA RIOJA.

TETTAMANTI, MAGDALENA; ECHEVESTE, HORACIO; AGUILERA, YOLANDA

Congreso; XIII CONGRESO DE MINERALOGÍA, PETROLOGÍA ÍGNEA Y METAMÓRFICA, Y METALOGÉNESIS (XIII MINMET ? IV PIMMA); 2019

Asociación Mineralógica Argentina y Asociación Geológica Argentina

Petrology of mafic dikes swarm intruded into the Ñuñorco Granite in the area of ?Cuesta de Miranda?, Famantina system, La Rioja. In this research we state that the mafic dikes of ?Cuesta de Miranda? are made up of a basaltic, subalkalic, calcoalkalic and metaluminous compositions. According to their textural and mineral characteristics, they are classified as microgabbros.According to the geochemical interpretation, the mafic dikes are a product of little differentiated magmas with arc magmatic characteristics and they were seated during an extensional event in the back-arc basin, in a subduction context.On the other hand, the finding of a dike intruded into the Pircas formation expands temporarily the intrusion event to the late Carboniferous or early Permian, and therefore the extensive event would have continued during the Paganzo II deposition.