%0 Journal Article
%T A Toarcian retro-arc basin of Central Patagonia (Chubut), Argentina: Middle Jurassic closure,arc migration and tectonic setting
%A Su¨¢rez
%A Manuel
%A M¨¢rquez
%A Marcelo
%J Revista geol¨®gica de Chile
%D 2007
%I Scientific Electronic Library Online
%R 10.4067/S0716-02082007000100004
%X the chubut basin (new name for the £¿liassic western chubut basin£¿ of other authors), developed during the early jurassic in the western part of central extra-andean patagonia in argentina (42¡ã30£¿s and 44¡ã30£¿s), accumulated shallow marine and continental sedimentary beds, with pyroclastic input, of the osta arena formation and equivalent units. to the west it was bounded by a coeval subduction-related magmatic arc (subcordilleran plutonic belt) and a subduction complex of late triassic-early jurassic age (chonos metamorphic complex). in turn, the eastern basin floor developed over the remnants of a previous late triassic-earliest jurassic magmatic arc (batholith of central patagonia) and over neopaleozoic sedimentary rocks of an accretionary prism. to the east, the basin was limited by a toarcian volcanic system associated to the karroo plume. the western magmatic arc continued to the north, where it is represented by the icalma member of the nacientes del biob¨ªo formation, bounding this time the neuqu¨¦n basin developed to the east. the closure of the toarcian basin in the middle jurassic coincides in time with a migration to the southwest of the toarcian magmatic arc, from a position in central extra-andean patagonia and a nnw orientation, to a location in the patagonian cordillera and a north-south orientation. synchronously, rift-related anatectic silicic volcanism developed east of the basin. hence, a major change in tectonic setting took place during the middle jurassic. it is here proposed that the migration of the arc was related to the growth of a plume under north-eastern patagonia
%K retro-arc basin
%K subduction
%K plume
%K patagonia
%K argentina.
%U http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0716-02082007000100004&lng=en&nrm=iso&tlng=en