Person:
Galindo Francisco, María Del Carmen

First Name

María Del Carmen

Last Name

Galindo Francisco

URI

https://hdl.handle.net/20.500.14352/81297

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Geológicas

Department

Mineralogía y Petrología

Area

Petrología y Geoquímica

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Now showing 1 - 10 of 25

The evolution of a mid-crustal thermal aureole at Cerro Toro, Sierra de Famatina, NW Argentina
(Lithos (Oslo. Print), 2014) Alasino, Pablo H.; Casquet Martín, César; Larrovere, M.A.; Pankhurst, R.J.; Galindo Francisco, María Del Carmen; Dahlquist, Juan A.; Baldo, Edgardo G.; Rapela, Carlos W.
A sheeted tonalite complex at Cerro Toro in western Sierra de Famatina, Argentina, was emplaced in the middle crust during an early phase of the Ordovician Famatinian orogeny. The intrusion produced a large-scale thermal aureole that provoked significant melting of the host rocks and hybridization of the anatectic melts with the tonalitic magmas. Three zones were distinguished in a cross-section: (1) an external zone consisting of metatexitic gneisses, amphibolites and minor tonalites, (2) an intermediate zone formed by screens of highly melted gneisses and amphibolites lying between the tonalite sheets: stoped blocks of gneisses within the tonalite sheets, small bodies of metagabbro and hybrid rocks are common in this zone, (3) an internal zone formed almost exclusively of massive tonalite. Incongruent melting of biotite in gneisses of the intermediate zone produced abundant cordierite and garnet; anatectic granitoids developed in the innermost part at 750–800ºC and ca. 5kbar. High water activities within this zone eventually promoted significant melting of plagioclase + quartz in the gneisses. Pooling of anatectic magmas resulted in allochthonous bodies of variable size either concordant or discordant to the regional structural grain, and part were retained in or close to the residuum. Allochthonous granitoids did not reach isotopic equilibrium with the source protolith probably due to fast extraction of the melts. The Cerro Toro contact aureole shows that assimilation of metasedimentary rocks through partial melting can be an important mechanism during emplacement of tonalitic magmas at middle crust levels. Thus the chemistry of cordilleran magma can be modified as they rise through the crust.
Thermal maturation of a complete magmatic plumbing system at the Sierra de Velasco, Northwestern Argentina
(Geological magazine, 2021) Macchioli Grande, Marcos; Alasino, Pablo H.; Dahlquist, Juan A.; Morales Cámera, Matías M.; Galindo Francisco, María Del Carmen; Basei, Miguel A.S.
The formation of magmatic plumbing systems in the crust involves mass and heat transfer from deep to shallow levels. This process modifies the local geotherm and increases the thermal maturation of the crust, affecting the rheological state of the host rock and the composition of magma. Here, we report a petrological, geochemical, isotopic and geochronological integrated study of the Huaco (354 Ma) and Sanagasta (353 Ma, from a new U–Pb zircon age) units from the Carboniferous (Lower Mississippian) Huaco Intrusive Complex, NW Argentina. Similar values of ϵNdt and δ18O, of −3.2 ± 0.7 and +11.2‰ ± 0.3‰ (V-SMOW), respectively, for both units indicate that they shared the same source, as a result of mixing and later homogenization of a crustal component at the Late Devonian (378 to 366 Ma), with metasomatized mantle-derived melts. Slightly higher contents of TiO2, FeO, MgO, CaO and rare earth elements for the Sanagasta unit in comparison with the Huaco unit suggest an increase in the degree of partial melting, which may have been caused by a higher temperature at the lower crust. In addition, the previous structural model of the Huaco Intrusive Complex points to an increase in thermal maturation in the upper crust, which drives a change in the emplacement style from tabular subhorizontal (Huaco) to vertically elongated (Sanagasta) bodies. Therefore, the evolution of the intrusive complex may reflect a generalized thermal maturation of the complete magmatic column, at both upper and lower crustal levels.
The Faja Eruptiva of the Eastern Puna and the Sierra de Calalaste, NW Argentina: U–Pb zircon chronology of the early Famatinan orogeny
(Journal of iberian geology, 2021) Casquet Martín, César; Alasino, Pablo H.; Galindo Francisco, María Del Carmen; Dahlquist, Juan A.; Baldo, Edgardo G.; Ramacciotti, Carlos; Verdecchia, Sebastián; Larrovere, Mariano Alexis; Rapela, Carlos W.; Recio, C.
The Famatinian is a segment of the Ordovician Terra Australis accretionary orogen that stretched along the SW Margin of Gondwana from Australia to Colombia. The present knowledge of this orogenic segment still is incomplete. We present geochemistry and U–Pb SHRIMP zircon geochronology of igneous and metamorphic rocks from the Central Famatinian Domain, one of the several domains recognized by Rapela et al. (Earth Sci Rev 187: 259–285. https://doi.org/10.1016/j.earscirev.2018.10.006) that includes the northern Sierras Pampeanas and the southern Puna of North West Argentina. Six samples of igneous rocks (peraluminous granitoids, mafic and felsic rocks, volcanic/subvolcanic rocks) and six samples of associated meta-sedimentary rocks, all from the Puna were dated and chemically analysed. The results indicate that the Central Famatinian Domain is in turn a composite domain that includes a Cordilleran-type magmatic arc (ca. 470 Ma) and a yuxtaposed fault-bounded older terrain formed in an extensional setting at the very start of the Famatinian orogeny, between 480 and 485 Ma, i.e., shortly after the SW Gondwana margin switched from passive to active. This short period of extension with related sedimentation, volcanism and mainly granitoid plutonism has not been previously recognised. It occurred before the Cordilleran-type magmatic arc -that resulted from a magmatic flare-up between ca. 473 and 468 Ma-, set up coincident with a contractional phase. The evidence confirms that accretionary orogeny results from tectonic switching (pull–push orogeny) and that the extensional and contractional phases are of relatively short duration.
Early Carboniferous sub- to mid-alkaline magmatism in the Eastern Sierras Pampeanas, NW Argentina: A record of crustal growth by the incorporation of mantle-derived material in an extensional setting
(Gondwana research, 2012) Alasino, Pablo H.; Dahlquist, Juan A.; Pankhurst, R.J.; Galindo Francisco, María Del Carmen; Casquet Martín, César; Rapela, Carlos W.; Larrovere, M.A.; Fanning, C.M.
A recently discovered granitic intrusion at Cerro La Gloria in western Sierra de Famatina (NW Argentina) is representative of sub- to mid-alkaline Carboniferous magmatism in the region. The main rock type consists of microcline, quartz and plagioclase, with amphibole, magnetite, ilmenite, biotite, epidote, zircon, allanite and sphene as accessory minerals. We report a U–Pb zircon SHRIMP age for the pluton of 349±3 Ma (MSWD=1.1), i.e., Tournaisian. Whole-rock chemical composition and Nd isotope analyses are compatible with an origin by melting of older mafic material in the lower crust (εNdt between −0.58 and +0.46 and TDM values of about 1.1 Ga). The pluton is intruded by penecontemporaneous to late alkaline mafic dykes that are classified as back-arc basalts. Coeval, Early Carboniferous A-type granites occur farther east in the Sierras Pampeanas, probably generated during lithospheric stretching. Overall, the Early Carboniferous granitic rocks show a west-to-east mineralogical and isotopic zonation indicating that magma genesis involved a greater contribution of juvenile material of mantle character to the west. Based on the observed patterns of geochronology, geochemistry and field relationships we suggest that A-type magma genesis in the Eastern Sierras Pampeanas was linked to an Andean-type margin where the lithospheric mantle played a role in its generation.
Diferencias entre granates de rocas ígneas y metamórficas de edad Famatiniana (Ordovícico), en las Sierras Pampeanas (Argentina)
(Macla, 2006) Dahlquist, Juan A.; Alasino, Pablo H.; Galindo Francisco, María Del Carmen; Casquet Martín, César
Los granates metamórficos de los esquistos de la zona de la biotita de la sierra de Chepes son ricos en Mn y tienen composiciones muy parecidas a la de los granates ígneos de diferentes rocas graníticas de edad Famatiniana (Ordovícico) de la misma región. Por tanto, el contenido de Mn, por sí mismo, no es suficiente para discriminar el origen de estos minerales, que pueden presentarse como cristales ígneos o como xenocristales en el granito. Por el contrario, el tipo de zonación del Mn permite distinguir entre ambas situaciones, al menos en el caso de granitoides cristalizados por encima de 700ºC.
Evolución magmática del Granito Peñón Rosado, cerro Asperecito, flanco occidental de la Sierra de Famatina
(Revista de la Asociación Geológica Argentina, 2006) Dahlquist, Juan A.; Alasino, Pablo H.; Galindo Francisco, María Del Carmen; Rapela, Carlos W.; Saavedra, Julio; Casquet Martín, César; Baldo, Edgardo G.; González Casado, José Manuel; Fanning, C.M.
El granate es un mineral accesorio poco común en rocas ígneas y constituye un tema relevante de la petrología ígnea. Estudios combinados de petrología, química mineral, geoquímica de roca total y geoquímica isotópica en el cerro Asperecito indican que los granitoides con granate que forman el Granito Peñón Rosado (GPR) fueron producidos por la fusión parcial de rocas metasedimentarias con subsecuente diferenciación durante su emplazamiento en el Ordovícico temprano-medio. En este sentido, la facies GPR1 representa un cristalizado temprano, la facies GPR2 representa un fundido diferenciado, y la facies GPR3 un fundido residual. El Granito Peñón Rosado, fue emplazado en condiciones de alta temperatura (785ºC) y presión media (4,4 kb) en profundidades de la corteza media ( 15 km). El emplazamiento casi sincrónico en la corteza media de una abundante suite metaluminosa durante el Ordovícico inferior-medio (468 Ma en el cerro Asperecito) fue suficiente para inducir anatexis local de los metasedimentos circundantes. Los contenidos de elementos mayoritarios (CaO, Na2O) y elementos traza (Rb, Sr, Ba) en el Granito Peñón Rosado sugieren anatexis a partir de un material inmaduro acumulado en un plataforma continental. Así, el Granito Peñón Rosado es un típico granitoide tipo-S con granate y el modelo establecido aquí puede contribuir a un mejor entendimiento acerca de la cristalización del granate en rocas graníticas.
Famatinian cordierite-bearing magmatism on the proto-Andean margin of Gondwana
(Libro de resúmenes: Geosur 2007. Un congreso sobre geología y geofísica del Hemisferio Sur, Santiago de Chile, 18 al 20 de noviembre de 2007, 2007) Alasino, Pablo H.; Dahlquist, Juan A.; Rapela, Carlos W.; Galindo Francisco, María Del Carmen; Casquet Martín, César; Pankhurst, R.J.; Saavedra, Julio; Baldo, Edgardo G.; Demant, A.; Hervé, F.; Menichetti, M.; Tassone, A.
Plutón La Costa, una expresión de magmatismo tipo-s en el sector noreste de la Sierra de Velasco, Sierras Pampeanas.
(Revista de la Asociación Geológica Argentina, 2006) Alasino, Pablo H.; Dahlquist, Juan A.; Galindo Francisco, María Del Carmen; Casquet Martín, César
Estudios combinados de petrología, química mineral y geoquímcia de roca total revelan la presencia de dos unidades graníticas peraluminosas con minerales aluminosos magmáticos tales como granate y mica blanca y la presencia distintiva de turmalina. Las evidencias aquí presentadas indican que estas dos facies, Anillaco y Anjullón, junto a la unidad peraluminosa Santa Cruz estudiada en trabajos previos, constituyen una serie de rocas co-sanguíneas, emplazadas en niveles someros de la corteza y las cuales conforman una unidad ígnea mayor denominada aquí plutón La Costa, la cual aflora en el sector noreste de la sierra de Velasco. La asociación mineral, la química mineral y la geoquímica de roca total permiten definir al plutón La Costa como un clásico granitoide tipo–S, derivado de una roca fuente de composición esencialmente pelítica. Diferentes estudios demuestran que la generación de granitoides tipo-S requiere de un alto gradiente geotérmico, por lo cual el plutón La Costa indica que la corteza en esta región soportó un notable calentamiento durante la generación del magma. Sin embargo, la ausencia de datos geocronológicos impide definir el evento tectomagmático que produjo el magma primordial de este plutón. [ABSTRACTS] La Costa pluton, an expresion of S- type magmatism in the northeastern sector of the Sierra de Velasco, Sierras Pampeanas. Combined petrology, mineral chemistry and whole-rock geochemistry studies reveal the presence of two peraluminous granitic units with magmatic aluminous minerals, such as garnet and white mica, and the distinctive presence of tourmaline. The evidence presented here indicates that these two facies, Anillaco and Anjullón, together with the peraluminous Santa Cruz unit studied in previous works, constitute co-sanguineous rocks, emplacemed in shallow levels of the crust, conforming a greater igneous unit, named here as La Costa pluton, that outcrops in the northeast sector of the sierra de Velasco. The mineral assemblage, the mineral chemistry and the whole-rock geochemistry allow defining the La Costa pluton as classic S-type granitoids, derived of a source rock of dominant pelitic composition. Several studies demonstrate that a high geothermal gradient is required for the generation of S-types granitoids, thus the La Costa pluton indicates that the crust supported a remarkable heating in this region during the generation of the magma. However, the absence of geochronological data prevents identification of the tectomagmatic event that yielded the parental magma of this pluton.
Magmatically folded and faulted schlieren zones formed by magma avalanching in the Sonora Pass Intrusive Suite, Sierra Nevada, California
(Geosphere, 2019) Alasino, Pablo H.; Ardill, K.; Stanback, J.; Paterson, S. R.; Galindo Francisco, María Del Carmen; Leopold, M.
The southwestern margin of the Late Cretaceous Sonora Pass Intrusive Suite, northern Sierra Nevada, California (USA), preserves a densely populated zone of magmatic structures that record dynamic magmatic layer formation and deformation (faulting and folding) within a solidifying upper-crustal magma mush. This zone consists largely of coupled melanocratic (or schlieren) and leucocratic bands hosted within the 95.6 ± 1.5 Ma Kinney Lakes granodiorite (Leopold, 2016), with orientations approximately parallel to the intrusive margin and with inward younging directions. Schlieren consist of a high modal abundance of medium-grained ferromagnesian minerals (hornblende + biotite), zircon, sphene, apatite, opaque minerals, and minor plagioclase and interstitial quartz. Leucocratic bands are dominated by coarse-grained feldspar + quartz with minor ferromagnesian and accessory minerals. Whole-rock geochemical and Sr and Nd isotopic data indicate that the schlieren are derived from the Kinney Lakes granodiorite by effective mechanical separation of mafic minerals and accessory phases. We interpret that the schlieren zone at the margin of the Kinney Lakes granodiorite formed by large-scale collapse of crystal mush by “magma avalanching,” facilitated by gravity, local convection, and possibly by host-rock stoping at the margin. This process eroded a significant portion of the solidifying margin of the chamber and resulted in the formation of magmatically deformed layered structures, which experienced further mingling, re-intrusion, magmatic erosion, and recycling processes. We envisage that magma avalanching of magma mushes in plutons can be achieved by any unstable process (e.g., tectonic, fluid-assisted, stoping, or gravity-driven) in large, long-lived magma-mush chambers.
Magmatic evolution of the Peñón Rosado granite: Petrogenesis of garnet-bearing granitoids
(Lithos, 1995) Dahlquist, Juan A.; Galindo Francisco, María Del Carmen; Pankhurst, R.J.; Rapela, Carlos W.; Alasino, Pablo H.; Saavedra, Julio; Fanning, C.M.
Garnet is an uncommon accessory mineral in igneous rocks but is petrologically significant. The Peñón Rosado granite (469± 4Ma) at Cerro Asperecito is an S-type granite that contains an unusual amount of magmatic garnet. Combined petrology, chemistry/ mineralogy and whole-rock geochemistry indicates that the magma was produced by partial melting of the surrounding metasedimentary rocks and subsequent differentiation by fractional crystallization during emplacement, with garnet occurring throughout the crystallization sequence. Three facies are recognised: PRG1 (SiO2=65.70%) represents cumulates, PRG2 (SiO2=70.88%) represents a differentiated melt, and PRG3 (SiO2=74.59%) a residual melt. The fractionation of Mn in garnet and the proportion of garnet crystallizing are roughly controlled by the evolving composition of the different granitic facies.Geothermobaric calculations reveal an initial crystallization temperature of 764°–792 °Cand a pressure of 5.9–6.0 kb, indicating that the parental magma was emplaced atmiddle crustal depths (∼1920 km) in moderate–low magmatic temperature conditions.Major (CaO, Na2O,K2O) and trace element (Rb, Sr, Ba) contents in the Peñón Rosado granite strongly suggest anatexis was the outcome of H2O-fluxed melting of metagreywacke, with heat input from a major metaluminous suite. Our studies reveal that garnet formed by direct crystallization from peraluminous magma in equilibrium with solid phases such as biotite and white mica.We confirm previous suggestions that zoning in garnet is strongly temperature-dependent. Thus, magmatic garnets in granitic rocks crystallized above ∼ 700 °C have “spessartine inverse bell-shaped profile” or are unzoned, whereas garnet exhibiting “spessartine bell-shaped profile” must be considered of metamorphic origin (i.e., xenocrystic) or formed in very felsic magmas (SiO2=73–76%) crystallizing below ∼ 700 °C. © 2006 Elsevier B.V. All rights reserved.