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The granulite-complexes of the Sierras de Córdoba, inside context of Sierras Pampeanas, expose the deeply-uplifted internal metamorphic zone of an early Cambrian orogen. One of the largest granulite-complexes in the north-central of Sierra de Comechingones consists mainly of a set of stromatic and diatexitic migmatites all derived from metasedimentary progenitors. Migmatites vary over a spectrum of morphologies ranging from patch, net, and stromatic metatexites to schollen-schlieren and nebulite diatexites with widespread interspersed anatectic granites. The granulite-complex subordinately includes amphibolites, marbles, serpentinized ultramafic rocks, and mafic plutonic rocks. Petrographic analysis, textural and structural interpretation, thermobarometric estimates, and inherited and metamorphic zircon dating reveal the metamorphic history of migmatites in the north-central part of the Sierra de Comechingones. Metastable preservation of kyanite reflects that migmatites were buried (0.69–0.78 GPa) and heated (~650 °C) along a prograde trajectory before the onset of extensive anatexis. Then migmatites were further heated to granulite-facies peak temperatures (≥800 °C) at similar pressures (0.77 ± 0.06 GPa) through the sillimanite stability field. Widespread partial melting of the metasedimentary sequence occurred during peak metamorphism. The entire granulite-complex cooled to temperatures below 550 °C and ascended to middle crustal depths (0.3–0.5 GPa). The prograde heating trajectory and decompression during uplift overcoming cooling and tectonic exhumation are compatible with a predominantly compressive deformation. Coeval widespread partial melting with contractional non-coaxial deformation triggered self-reorganization of anatectic melts giving rise syn-deformational migmatites. In all the analyzed migmatites, U–Pb zircon geochronology yields inherited ages corresponding to those of orogenic systems that characterize the West Gondwana supercontinent. Inherited ages show a polymodal distribution pattern with contributions from Neoproterozoic (551–734 Ma; i.e., Brasiliano - Pan-African) and Mesoproterozoic detrital zircons (850–1182 Ma; i.e., Grenvillian), and minor proportions of Paleoproterozoic zircon grains (1751–1839 Ma). Ages interpreted as metamorphism and anatexis suggest the development of a single metamorphic event and restricted anatexis to a relatively short period of about 15 Ma (ca. 540-525 Ma). Metamorphic ages associated with the metamorphic peak trajectory are related to the Cambrian Pampean Orogeny. • P-T- t path shows a clockwise evolution along a single metamorphic event. • U–Pb zircon geochronology constraints granulite-facies metamorphism to ~540-525 Ma. • Metamorphic evolution was coeval with a compressive non-coaxial deformation. • Metatexites and diatexites are Early Cambrian syn-deformational lithological products. [ABSTRACT FROM AUTHOR]

The Valle Fértil-La Huerta batholith is a differentially tilted, compositionally stacked, calc-alkaline plutonic sequence in the central Famatinian arc of Argentina. It consists of two major lithologic units: these are (1) an intermediate unit largely dominated by amphibole- and biotite-bearing tonalites but encompassing from gabbro to leucogranite; and (2) an overlying silicic unit that shows the same petrological diversity as the intermediate unit, but granodiorite and monzogranite are its prevailing lithologies. The silicic unit is separated into four subunits using lithological changes at regional mapping scale. All the boundaries are gradational among lithologic units and subunits. The internal fabric along the entire batholith is either magmatic or submagmatic and it was developed during the arc formation. The original magmatic foliation is north–south striking and steeply-dipping. The magmatic foliation crosses over and transposes the gradational contacts among lithologic units. Petrological architecture, structural geology, geobarometric estimates and geochronology show that the entire batholith is a comagmatic system exposing more than 13 km of a middle arc crust. Crystallization-fractionation models computed using whole rock and mineral chemistry account for the mineralogy of plutonic rocks and coincide with the results of experimental petrology. Mass-balanced modeling predicts that the unexposed cumulate roots of the Famatinian arc should have been about 1.3 times larger than the intermediate and silicic plutonic batholith. However, the mass of calculated cumulate would diminish significantly if a portion of the host metasedimentary material were consumed in constructing the batholith. The batholith grew progressing upward from the lowest levels and acquired a stratified compositional organization. The driving mechanism was continuous influxes of mantle-derived mafic magmas that made up the lower crust, caused crustal-level melting and magma mixing, and formed intermediate – silicic rocks at increasingly shallower depths. • The plutonic middle crust of the Famatinian arc was at least 13 km thick. • The plutonic crust grew progressing upward and acquiring a stratified organization. • Pre-arc metasedimentary sequences play a role in fertilizing the magmatic system. • Modeling yields a 1.3:1 ratio of cumulates over derivatives to make the magmatic column. • A few tens of kilometers of cogenetic cumulates are lost in the Famatinian arc. [ABSTRACT FROM AUTHOR]