Instituto de Fisiografía y Geología “Dr. A. Castellanos” (IFG)
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Ítem Acceso Abierto A new species of the ammonite genus Neochetoceras Spath (Oppeliidae) from the Hybonotum Zone (Lower Tithonian) of Southern Germany, with comments on the phylogeny of the genus(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 2015-09) Scherzinger, Armin; Parent, Horacio; Schweigert, GünterÍtem Acceso Abierto A new species of the ammonite genus Physodoceras Hyatt (Aspidoceratidae) from the Hybonotum Zone (Lower Tithonian) of Southern Germany, with comments on the phylogeny of the genus(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 2018-12-20) Scherzinger, Armin; Parent, Horacio; Schweigert, GünterÍtem Acceso Abierto A plastic rheology phenomenological 201 . model that explains the Andes evolution in northern Argentina(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 27/12/2012) Introcaso, Antonio; Giménez, Mario; Martínez, María Patricia; Ruiz, FranciscoA plastic rheology, partially phenomenological model is presented to explain the isostatically compensated Andean relief formation. This model considers a combination of lithospheric heating with long period relaxation and successive crustal shortenings on a north section of Argentina located at 24°S latitude. The present size of the Andean root –related to the Andes construction– was obtained by inverting regionalized Bouguer anomalies, also consistent with geoid undulations. The relief of 1520 km is balanced both with a thermal root of 70.63 km located at the lithospheric mantle and 2 with an evolutionary crustal root originated by shortenings. A pretended contradiction must be noted: lateral compressive shortenings and side moving tending to squash and to widen the high relief. For better understanding the problem, a linear model is first presented. Then, a nonlinear model of plastic rheology is considered with a stability coefficient depending on width and elevation. We have assumed that isostatic balance keeps on the whole orogenic construction. We also impose an empirical stability relationship. If this relationship does not hold, there will be an extra relief and therefore an extra root that will plastically flow until reaching stability.Ítem Acceso Abierto Aerofotointerpretación de un sector del Delta Entrerriano(Instituto de Fisiografía y Geología, 1976) Pasotti, Pierina; Canoba, Carlos A.; Catalani, Wally R.Ítem Acceso Abierto Alternative gravimetric methodology for isostatic analyses. An example for Bolivian Andes(Instituto de Fisiografía y Geología, 2008-12) Crovetto, Carolina Beatríz; Introcaso, AntonioIn this work we present a new, alternative methodology for performing isostatic studies by means of geoid undulations, excluding the use of measured gravity anomalies. An example on Bolivian Andes is presented as case study. Considering a digital elevation model as input data, a theoretical perfectly isostatically balanced Airy crustal model was constructed for Bolivia. The free-air and the Bouguer anomalies, and the geoid undulations produced by this theoretical model, were directly evaluated by means of three-dimensional integration. The “real” geoid undulations were computed from the EGM96 global geopotential model, and were filtered from long wavelengths by means of a sparse Fourier transform method. The residual “real” geoid undulations were compared with the theoretical geoid undulations for Bolivian Andes, showing a global tendency towards isostatic balance, agreeing with previous results obtained using traditional gravimetry. The free-air and the Bouguer anomalies from the EGM96 residual geoid undulations were also evaluated and then compared with the anomalies produced by the theoretical model. The Bouguer anomalies support definitely the results obtained using the geoid undulations while the free-air anomalies, although less consistently, showed the same global tendency.Ítem Acceso Abierto Ammonites cretácicos de la formación río Mayer (Patagonia Austral) Hatchericeras patagonense Stanton (Barremiano) y Sanmartinoceras patagonicum Bonarelli (Albiano)(Instituto de Fisiografía y Geología, 1991) Parent, HoracioÍtem Acceso Abierto Ammonites of the Middle Tithonian Internispinosum Zone from Barda Negra, southern Neuquén-Mendoza Basin, Argentina(Instituto de Fisiografía y Geología, 2007) Parent, Horacio; Scherzinger, Armin; Schweigert, Günter; Capello, Oscar D.An ammonite fauna from an isolated outcrop of the Upper Jurassic Vaca Muerta Formation is described from Barda Negra in the southern part of the Neuquén-Mendoza Basin. It comprises several macroconch specimens of the species Aspidoceras cf. euomphalum Steuer, 1897 besides macroconchs and microconchs of Windhauseniceras internispinosum (Krantz, 1926), the index species of the Andean Middle Tithonian Internispinosum Zone. Morphological and taxonomic relationships of the studied aspidoceratids with previously described species and the sexual dimorphism in W. internispinosum are discussed.Ítem Acceso Abierto Análisis hipsométrico, frecuencia altimétrica y pendientes medias a partir de modelos digitales del terreno(Instituto de Fisiografía y Geología, 2007) Racca, Juan Manuel GonzaloHypsometric analysis, altimetric frequency and mean slopes obtained from digital terrain models. The techniques and software tools which allow the realization of the hypsometric analysis and to obtain the altimetric frequency and mean slopes curve of areas of the earth surface, particularly of hydrographic basins, operating on digital terrain models, are presented. The example of the total anthropized basin of the Arroyo del Medio (Santa Fe and Buenos Aires provinces), is included.Ítem Acceso Abierto Análisis planimétrico de cuencas hidrográficas utilizando la Lemniscata Asociada(Instituto de Fisiografía y Geología, 1980) Racca, Juan Manuel GonzaloÍtem Acceso Abierto Andean Lower Tithonian (Picunleufuense Zone) ammonites and aptychus from Estancia Maria Juana, Southern Neuquén Basin, Argentina(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 2013-12-27) Parent, Horacio; Garrido, Alberto C.; Schweigert, Günter; Scherzinger, ArminÍtem Acceso Abierto Anomalous upper mantle beneath the Central Andes : isostasy and Andean uplift(Instituto de Fisiografía y Geología, 2001) Introcaso, AntonioFour theoretical models isostatically compensated were prepared and compared between themselves in order to analyze either the isostatic equilibrium or the probable mechanisms for justifying the Central Andean uplift. They are: Model 1, or Airy Model: in this classical model the isostatic compensation would take place at the maximum Moho depth's level: 61.7 km. Model 2: this model justifies the Andean elevation by means of a combination of lithospherical thermal root and crustal root. In this case, the last one is diminished 5.3 km respect to crustal root's thickness of Model 1. Isostatic compensation takes place here at the bottom of thermal lithosphere: 140 km deep. Model 3: this model explains the elevation by means of a combination of the subsidence that the subducted Nazca Plate could produce, and the crustal root effect, that is 6 km thicker than the first model's root. The isostatic compensation could take place at a depth of 300 km. Model 4: this model involves Models 1, 2 and 3 mechanisms; the isostatic compensation takes place at a depth of 300 km. Crustal shortenings S are sensitive to the upper mantle's heterogeneity, varying from 17% to +18%, h as it is shown by the following values: S = 278 km (Model 1), S = 230 km (Model 2), S = 338 km (Model 3) and h h h S = 288 km (Model 4). h We also demonstrate that the model selected for evaluating the Andean isostatic equilibrium in this zone of the anomalous upper mantle is not critical. The analysis of the two EW gravity sections at 22°S and 24.5°S latitudes favors Model 2 as the most likely, since the crustal thickness found from it is clearly consistent with seismic data available at 24.5°S. Nevertheless, we can admit other gravimetric models.Ítem Acceso Abierto Anotaciones sobre la línea filogenética de los clamiterios(Instituto de Fisiografía y Geología, 1937) Castellanos, AlfredoÍtem Acceso Abierto Autoendomorphisme et la nature électromanétique : de la gravitation et les théories de Laplace, de Thomas C. Chamberlin et D. R. Salisbury, sur l'origine des planètes(Instituto de Fisiografía y Geología, 1939) Sagui, Cornelio L.Ítem Acceso Abierto Bibliografía de Pierina Pasotti(Instituto de Fisiografía y Geología, 2000) Parent, Horacio; Peralta, EduardoÍtem Acceso Abierto Breve nota sobre la morfología de un sector de la llanura chaqueñas (Argentina)(Instituto de Fisiografía y Geología, 1967) Pasotti, Pierina; Castellanos, AlfredoÍtem Acceso Abierto Callovian nautiloids from the Neuquén Basin, Argentina(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 2015-09) Parent, Horacio; Garrido, Alberto C.Ítem Acceso Abierto Caracterización climática del área de la Cuenca del Arroyo del Medio(Instituto de Fisiografía y Geología. Facultad de Ciencias Exactas, Ingeniería y Agrimensura. Universidad Nacional de Rosario, 2010-02) Sacchi, OscarLa presente contribución ofrece una caracterización climática del área en la que se emplaza la Cuenca del Arroyo del Medio. Los principales parámetros que definen el clima regional (temperaturas medias estacionales, régimen de heladas, precipitaciones medias estacionales) fueron obtenidos del estudio de información disponible del período 1961-1990 provenientes de registros de 5 estaciones que rodean el área estudiada. Los resultados del balance hidrológico practicado muestran que los excesos de agua se producen en los meses de Junio a Octubre, y las deficiencias se producen en los meses Enero y Febrero. Los resultados se presentan en mapas regionales que permitieron la detección de dos gradientes principales: (1) tendencia Oeste- Este del régimen de precipitaciones, y (2) un gradiente térmico Sur-Norte.Ítem Acceso Abierto Cómo se inició y desarrolló mi dedicación a la fotointerpretación(Instituto de Fisiografía y Geología, 2000) Pasotti, PierinaÍtem Acceso Abierto Construcción de un radiómetro diferencial para espectrocopía en el infrarrojo(Instituto de Fisiografía y Geología, 1943) Levialdi, AndrésÍtem Acceso Abierto Contribución al conocimiento de la laguna Melincué(Instituto de Fisiografía y Geología, 1984) Pasotti, Pierina; Albert, Oscar A.; Canoba, Carlos A.