Significance of the early Jurassic Garamilla formation in the Western Nordpatagonian Massif

By means of facial, stratigraphic, petrographic, geochemical and geochronological studies we characterize the Garamilla Formation, cropping out in the western Nordpatagonian Massif. The studies of these volcanic rocks reveal an Early Jurassic volcanic episode calc-alkaline series. Other geochemical features reveal a progressive change formed by three volcanic units that change from normal calc-alkaline to high-K 13 from an initial subduction-related volcanism to one intraplate-related volcanism. This volcanic episode is temporally and geochemically equivalent to those volcanic units located in half-grabens in several areas of the Neuquén Basin. The volcanic units were erupted in different structural designs. A portion of its depocenter was interpreted as a transtensional half-graben whereas the other exhibits a trapdoor structure. The lineament trends that bound the volcanic system were also recognised in Western Nordpatagonian Massif, and were assigned to the Gondwanide Orogenic.Fil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina;Fil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina

The Gondwana-South America Iapetus margin evolution as recorded by Lower Paleozoic units of western Precordillera, Argentina: The Bonilla Complex, Uspallata

Terrane, accreted to Gondwana South America during Ordovician times. The Bonilla Complex, which represents the southern tip of the Precordillera, is constituted of metasedimentary rocks of internal and external platform environments. Paleocurrents inferred from sedimentary structures indicate provenance from the northeast and southeast (actual coordinates). The limestones of this complex, located in the eastern part of the outcrops, suggest evolution toward a carbonate-dominated Late Neoproterozoic to Cambrian passive margin. Mafic volcanic rocks were emplaced coevally with sedimentation, whereas ultramafic rocks were later tectonically emplaced. Chemical evidence suggests that the protolith of the metasedimentary rocks was derived from an older exhumed felsic basement belonging to an upper continental crust. The most prominent population of detrital zircons (~500- 600 Ma) from the Bonilla Complex support the hypothesis that these rocks are equivalent to those of the Sierras Pampeanas and the northern Patagonia. The most proximal source of the Pampean zircons found in the Bonilla Complex is the Sierras Pampeanas, located immediately to the east (present coordinates). The Bonilla Complex was deposited in an open marine basin considerably earlier (~50 Ma) than the supposed detachment of the Cuyania Terrane from the Ouachita embayment in the Laurentia margin. It is therefore not necessary to invoke the presence of an allochthonous terrane between the Bonilla Complex and the Gondwana margin to explain the 1 Ga zircon populations. Silurian to Devonian deformation was characterized by metamorphism and imbrication within an accretionary prism, the consequence of eastward subduction in the western margin of Gondwana. Therefore, the Bonilla Complex, as well as equivalent units in western Precordillera, was originally deposited as sediments on a continental shelf at the southwestern margin of Gondwana, covering a basement that was already part of the Gondwana continent by Neoproterozoic-Cambrian times.Fil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina;Fil: Martinez, Juan Cruz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina;Fil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina

Characterization of Fiber Types in Different Muscles of the Hindlimb in Female Weanling and Adult Wistar Rats

We analyzed lesser diameter and distribution of fiber types in different skeletal muscles from female Wistar rats using a histoenzymology Myofibrillar Adenosine Tri-phosphatase (mATPase) method. Fragments from muscles were frozen and processed by mATPase in different pH. Adult and weanling rat soleus muscles presented a predominance of type I fibers and larger fiber diameters. In the plantar muscle in adult rats, the type IIB fibers demonstrated greater lesser diameter while in the weanling animals, types I and IIB fibers were larger. The plantar muscle of animals of both ages was composed predominantly of the type IID fibers. The type IID fibers were observed in similar amounts in the lateral gastrocnemius and the medial gastrocnemius muscles. Type IIB fibers showed predominance and presented higher size in comparison with other types in the EDL muscle. The present study shows that data on fiber type distribution and fiber lesser diameter obtained in adult animals cannot always be applied to weanling animals of the same species. Using the mATPase, despite the difficult handling, is an important tool to determine the different characteristics of the specific fibers in the skeletal muscle tissue

Lower Jurassic felsic diatreme volcanism recognized in central Patagonia as evidence of along-strike rift segmentation

The early Jurassic volcanism of Central Patagonia covers an extensive area of50,000 km2 where the volcanic deposits occur as isolated systems. The volcanicrecords form an elongated belt in which the composition, depositional and geneticfeatures, show several differences along with its distribution. The Cañadón ChilenoComplex (CCHC), located in the Río Negro province, provides the opportunity toevaluate and improve the knowledge about the Lower Jurassic volcanic stratigraphyand the lower Jurassic regional setting of Central Patagonia.Based on the field and laboratory data developed in the present work, 22lithofacies were recognized and grouped into eight facies associations. Thecontinental sedimentary environments include alluvial fan deposits (FA 1),ephemeral deposits (FA 2), braided fluvial deposits (FA 3), alluvial plains, or overbanks (FA 4), and lacustrine deposits (FA 9). On the other hand, the pyroclasticfacies were separated according to the pyroclastic currents involved during thedeposition; into fall-out, dilute, and density currents (FA 5, FA 6, and FA 7). Effusiveandesitic feeders and lava-flows (FA 8) were also recognized.The stratigraphic data obtained in the present work allow proposing theexistence of two felsic diatreme volcanoes in the CCHC records - described here asSouthern and Northern Zone-, developed over a local subsided area, represented byan asymmetrical basin.Seven units were recognized and described in the CCHC (Units a, b, c, d, e, f,and g: unit (a) represents an initial stage of continental sedimentation recordedthroughout the entire Complex. Unit (b) represents the upper felsic diatreme facies,in Southern Zone of the Complex, where debris flows are interbedded with massive lapilli-tuff deposits. Unit (c) consists of local andesitic lavas flows and feeder dikes,and the unit (d) consists of welded lapilli tuff deposits interpreted as the growth of thevolcanic system. The Northern Zone evolves similarly with the felsic intra-diatremedeposits of unit (e). The unit (f) consisting of an effusive stage represented byextended andesitic lava flows. Finally, a deep lacustrine system is installed (unit g)that includes shallow and deep facies, with intercalations of local pyroclasticdeposits.Also, new geochronological data (U-Pb zircon age of 188 ± 3 Ma) wasdetermined to confirm and reinforce the correlation criteria between the differentvolcanic areas in Central Patagonia, indicating that the volcanism described here issynchronous with the Northern silica-rich calderas of the Garamilla Formation as wellas the large andesitic volcanoes of the Lonco Trapial Formation located southwardto the CCHC. The regional volcanism changes described, in the present work, areconnected with the N-S rift segment limited by E-W regional transfer fault systemsdeveloped in continuity to the strike-slip structures of the La Esperanza area.Fil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Pavon Pivetta, Cecilia Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Marcos, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Barros, Mercedes Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Scivetti, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Santos, Anderson Costa dos. Universidade do Estado do Rio de Janeiro. Faculdade de Geologia; Brasil. Universidade de Aveiro; PortugalFil: Strazzere, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Geraldes, Mauro. Universidad Estatal de Rio de Janeiro; BrasilFil: de Queiroz Bernabé, Teodoro. Universidad Estatal de Rio de Janeiro; Brasi

Late Paleozoic geodynamic evolution of the western North Patagonian Massif and its tectonic context along the southwestern Gondwana margin

In this study, we propose a geodynamic model covering sedimentation, metamorphism, magmatism, and exhumation processes for the western North Patagonian Massif basement. The youngest detrital zircon population ages (ca. 369 ± 8 Ma) obtained in a schist sample constrains the sedimentation stage to the Carboniferous Period. A first prograde metamorphic stage (M1-D1) produced the main foliation (S1) under greenschist conditions (~ 500 °C; < 4.5 Kbars). This stage was possibly linked to the regional Carboniferous magmatism event (330?300 Ma). The Permian magmatism (ca. 290 Ma) likely induced partial melting and migmatization of the deepest metasedimentary suite. This event corresponds to the second prograde metamorphic stage (M2) that reached amphibolite conditions (690 °C and 6.5 Kbars). The beginning of the basement uplift corresponds to the first retrograde metamorphic stage possibly developed during Permian ? Triassic times (265?235 Ma). This event was triggered by NE-SW compression (σ1) and developed folds (D2-F2), second foliation (S2), micro-textural quartz deformation, and a retrograde evolution path for the garnet-bearing lithofacies. The final stage of the basement exhumation corresponds to the second retrograde metamorphic stage (D3) developed by NNW-SSE compression and linked to open folds (F3) in the Cushamen Formation. The characteristics of the western North Patagonian Massif geodynamic evolution and the adjacent basement regions suggest a paleotectonic subduction setting for the southwestern Gondwana margin during the late Paleozoic times.Fil: Marcos, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Pavon Pivetta, Cecilia Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Geraldes, Mauro. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: Scivetti, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Barros, Mercedes Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Varela, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Santos, Anderson Costa dos. Universidade Federal do Estado do Rio de Janeiro; Brasi

Early Permian arc-related volcanism and sedimentation at the western margin of Gondwana: Insight from the Choiyoi Group lower section

Permian sedimentary and basic to intermediate volcanic rocks assigned to the Conglomerado del Río Blanco and Portezuelo del Cenizo Formation, lower part of the Choiyoi Group, crop out between the Cordon del Plata, Cordillera Frontal and Precordillera of Mendoza Province, Argentina. The sedimentary rocks are represented by six lithofacies grouped in three facies associations. They were deposited by mantled and gravitational flows modified by high-energy fluvial currents that evolved to low-energy fluvial and lacustrine environments. They constitute the Conglomerado del Río Blanco, which cover unconformably marine Carboniferous sequences. Five volcanic and volcaniclastic facies make up the beginning of volcanic activity. The first volcanic event in the Portezuelo del Cenizo is basaltic to andesitic lava-flows emplaced in the flanks of volcanoes. Lava collapse produced thick block and ash flows. Interbedding in the intermediate volcanic rocks, there are dacites of different geochemical signature, which indicate that the development of acidic volcanism was coetaneous with the first volcanic activity. The geochemistry of these rocks induces to consider that the Choiyoi Group Lower section belongs to a magmatic arc on continental crust. The age of this section is assigned to the lower Permian (277 ± 3.0 Ma, Kungurian age)

The Cordon del Portillo Permian magmatism, Mendoza, Argentina, plutonic and volcanic sequences at the western margin of Gondwana

The Cerro Punta Blanca, Cerro Bayo and Cerro Punta Negra stocks, parts of the Cordillera Frontal Composite Batholith, cropping out in the Cordón del Portillo, records the Gondwana magmatic development of the Cordillera Frontal of Mendoza, in western Argentina. In this area, the San Rafael Orogenic phase, that represents the closure of the Late CarboniferouseEarly Permian marine basins, begins at 284 Ma, and ceased before 276 Ma. The Cerro Punta Blanca, Cerro Bayo and Cerro Punta Negra stocks represent a post-orogenic magmatism and are equivalents to the Choiyoi Group. The Gondwana magmatic activity in the Cordón del Portillo area can be divided into two stages. The Cerro Punta Blanca stock (c.a. 276 Ma) represents an early post-orogenic, subduction-related magmatism similar to the basic-intermediate section of the Choiyoi Group (c.a. 277 Ma). The late post-orogenic second event was recorded by the Cerro Bayo (262 Ma) and Cerro Punta Negra stocks which represent a transition between subduction-related and intra-plate magmatism. This event represents the intrusive counterpart of the acidic facies of the upper section of the Choiyoi Group (c.a. 273 Ma). This extensional condition continued during the Triassic when the Cacheuta basin developedFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina;Fil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Bahia Blanca. Instituto Geológico del Sur; Argentina

The Garamilla Formation: Lower Jurassic volcanic eventin western Comarca Nordpatagónica, Río Negro province, Argentina

La Formación Garamilla aflorante en el borde occidental de la Comarca Nordpatagónica se halla integrada por rocas volcánicas y piroclásticas de composiciones andesitas, dacíticas y riolíticas cuya edad se extiende entre el Triásico Superior –Jurásico Inferior. Particularmente en la zona de los Puestos Quiñenao, Fuensalida y los cañadones Mencué, Blancura y Currú Mahuida aflora una secuencia de 800 m de espesor dentro de la cual fueron reconocidos tres eventos: Un evento inicial compuesto por domos, lavas riolíticas e ignimbritas “ lava- like” . Un segundo evento volcánico está representado por diques y lavas andesíticas a dacíticas, tobas lapillíticas y tobas lapillíticas eutaxíticas de composiciones dacíticas. El tercer evento se encuentra integrado por tobas, tobas reomórficas, tobas lapillíticas, brechas volcánicas monomícticas, brechas líticas masivas, lavas y diques Esta unidad conforma una serie calco-alcalina vinculada a un proceso de subducción. Una edad U-Pb 185±2 Ma (Pliesbaquiana) fue obtenida para la litofacies de tobas lapillíticas del segundo evento volcánico. Estas características permiten correlacionarla con el volcanismo calco-alcalino Jurásico Inferior desarrollado en la provincia de Neuquén.The Garamilla Formation: lower Jurassic volcanic event in western comarca nordpatagónica, río negro province, Argentina. The Garamilla Formation cropping out at the western edge of the Nordpatagonian Region is composed by volcanic and pyroclastic rocks of andesites, dacíticas and rhyolitic compositions whose age extends from the Late Triassic to Early Jurassic. In the area of the puestos Quiñenao, Fuensalida and cañadones Mencué, Blancura and Currú Mahuida appears a sequence 800 m thick where three volcanic events were recognized. The first one consists of domes and rhyolitic lavas, as well as lava-like ignimbrites. The second is represented by dikes and andesitic to dacitic lava flows, lapilli-tuffs and eutaxitic lapilli-tuffs of dacitic composition. The third event is made up of tuffs, rheomorfic tuffs, lapilli-tuffs, volcanic breccias, lava flows and dikes. This unit forms a calc-alkaline series related to a subduction process. An U-Pb age of 185 ± 2 Ma (Pliesbachian) was obtained for the lapilli-tuffs lithofacies of the second volcanic event. These features allow correlation with the Lower Jurassic calc-alkaline volcanism developed in the Neuquén province.Fil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; Argentin

Configuración paleogeográfica del Pennsylvaniano entre los 38° y 44° de latitud Sur

El basamento Paleozoico ubicado en el sector andino y extraandino entre los 38° y 44° de latitud Sur, presenta una serie de ciclos alternantes de sedimentación, metamorfismo y magmatismo (Pankhurst et al., 2006). El último ciclo de sedimentación correspondiente al Pennsylvaniano está caracterizado por la presencia de depósitos diamictíticos (Limarino y Spalletti, 2006). La distribución de estos registros, el contenido fosilífero y las recientes edades isotópicas (Hervé et al., 2005 y 2016; Duhart et al., 2009 y Taboada et al., 2011) permiten distinguir tres cuencas Pennsylvanianas y una serie de unidades pre-Pennsylvanianas consideradas como áreas de aporte. La cuenca ubicada en el extremo occidental del Macizo Nordpatagónico corresponde a las metadiamictitas de la Formación Cushamen. En el Chubut Extraandino, las sedimentitas de las formaciones Pampa de Tepuel y Las Salinas forman parte de la cuenca de Tepuel. Por último, las metasedimentitas de los complejos metamórficos Trafun y Bahía Mansa forman parte de la cuenca del centro sur de Chile. El área de aporte detrítico más antigua de estos depósitos corresponde a unidades que abarcan desde el Paleoproterozoico al Paleozoico medio ubicadas en la región oriental de los depocentros Pennsylvanianos. Por otra parte, las metasedimentitas y rocas ígneas del Complejo Colohuincul en la Cordillera Patagónica Septentrional habrían formado un positivo entre la cuenca del Macizo Nordpatagónico y la ubicada en la región centro sur de Chile. Por último, los cuerpos ígneos Carboníferos distribuidos en dirección NO-SE habrían formado un positivo entre la cuenca del Macizo Nordpatagónico y la cuenca de Tepuel.Fil: Marcos, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaVII Simposio Argentino del Paleozoico SuperiorEsquelArgentinaUniversidad Nacional de La Plata. Facultad de Ciencias Naturales y Muse

Lithofacial analyses of the "Estratos de Comallo", North Patagonian Massif, Río Negro Province, Argentina

En la zona de la Cantera Comallo fueron definidas cinco litofacies volcánicas, pertenecientes a los denominados Estratos de Comallo, con un espesor máximo de 84 metros. Litológicamente se componen de tobas lapillíticas, brechas líticas y tobas de grano fino que fueron agrupadas en tres asociaciones de facies, siguiendo los modelos propuestos para los flujos piroclásticos. Las mismas se originaron a partir de una erupción freatomagmática.In the area of the CanteraComallo five lithofacies belonging to the so-called Estratos de Comallo were defined. The maximum thickness of 84 m. Lithologically, they are compose of lapilli-tuffs, lithic breccias and fine-grained tuffs that were grouped in three facies associations following the models proposed for the pyroclastic flows. They originated from a phreatomagmatic eruption.Fil: Barros, Mercedes Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Gregori, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Marcos, Paulo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Benedini, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Strazzere, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaXX Congreso Geológico ArgentinoSan Miguel de TucumánArgentinaAsociación Geológica Argentin