Marine Isotope Stage 3 (MIS 3) is characterized by high climatic variability resulting from numer... more Marine Isotope Stage 3 (MIS 3) is characterized by high climatic variability resulting from numerous centennial to millennial scale events. The environmental and climatic reconstruction of this interval is restricted by the sparsity of high-resolution (centennial-scale) terrestrial records in most of South America. This contribution is an attempt to reconstruct the general environmental and climatic conditions of southern South America during MIS 3 by means of continental records located in central Argentina; this is an extensive and heterogeneous region made up of diverse geomorphological settings under different climatic conditions. Therefore, the main features of several aeolian and fluvial records situated in different geomorphological settings across the region are overviewed. The results indicate the predominance of regional aggradation during MIS 3 with differences in the accumulation rates and dominance of either aeolian or fluvial deposits depending on the geomorphological setting. The aggradation process was interrupted by stability intervals evidenced by paleosols in the San Rafael plain, the San Luis paleo-dunefield, the eastern Sierras Pampeanas piedmont and the eastern Pampean plain. The paleosols might represent lapses of decreasing aeolian input and perhaps more humid conditions. In addition, paleobiological indicators from alluvial sequences suggest higher temperatures and water availability between 35 and 31 ka in the Andean piedmont, while dry subhumid or strongly seasonal conditions with alternating subhumid-humid phases were inferred in the eastern Pampean plain during MIS 3. These intervals tend to cluster during the second part of MIS 3, and might reflect the environmental responses to some of the climatic oscillations that occurred during MIS 3. Detailed analysis and a more adjusted chronology are needed to correlate the aeolian and fluvial episodes along with the stability intervals at regional and continental scales.
The sanrafaelina plain is covered by aeolian and fluvial deposits, the former comprise, in some c... more The sanrafaelina plain is covered by aeolian and fluvial deposits, the former comprise, in some cases, large dune fields while the latter are associated to permanent and ephemeral rivers that drain this plain. The drainage network is made up of two main rivers (Diamante y Atuel) together with smaller, semipermanent or temporary, streams. Two of these streams, Agua del Chancho and La Hedionda creeks, are located in a transitional zone between a fluvially-dominated plain to the south (Diamante river plain) and an aeolian-dominated area to the north (Médanos de los Naranjos dune field). In this region three geomorphic units were recognized: a regional aggradational plain (sanrafaelina plain) and within the creek valleys a fill terrace and the present floodplain of the streams. These units are mainly composed of silty sands with a variable presence of gravel levels. Sedimentological analysis in the aggradational plain allowed to differentiate fluvial and aeolian-fluvial deposits at the ...
En los últimos años el delta del Paraná ha recibido una atención creciente de distintos profesion... more En los últimos años el delta del Paraná ha recibido una atención creciente de distintos profesionales, debido al rápido crecimientopoblacional de las islas del Tigre y de los municipios de San Isidro y San Fernando. Este hecho incrementó el valor económico eintensificó el uso de los recursos naturales en la zona. Este trabajo estudia el comportamiento del sector sureste del frente deltaicodel Paraná entre los años 1933 y 2016; con el objeto de registrar los cambios morfológicos recientes y sus rasgos dinámico-sedimentarios asociados. Los resultados obtenidos muestran que el frente deltaico ha tenido un avance episódico relacionado el adosamientode barras de desembocadura en la boca de los canales distributarios, incrementando la superficie y extensión de la planicie deltaicainferior. Estas barras se adosaron en las décadas 1935-50, 1960, 1980 y 2000. La velocidad de avance del frente deltaico varió de42,30 m/año a 45,13 m/año. Esta rápida progradación ha producido cambios naturales ...
Supplemental material, Supplementary_Material,_Table_B for Human occupation strategies and relate... more Supplemental material, Supplementary_Material,_Table_B for Human occupation strategies and related environmental-climate during the middle and late Holocene in central Pampas of Argentina by Pablo G Messineo, Marcela S Tonello, Silvina Stutz, Alfonsina Tripaldi, Nahuel Scheifler, Nélida Pal, Guillermina Sánchez Vuichard and Diego Navarro in The Holocene
En los ultimos anos el delta del Parana ha recibido una atencion creciente de geologos, biologos,... more En los ultimos anos el delta del Parana ha recibido una atencion creciente de geologos, biologos, arquitectos y planificadores ambientales debido al rapido crecimiento poblacional de las islas del Tigre y de los Municipios de San Isidro y San Fernando. Este hecho ha incrementado el valor economico de estos territorios e intensificado el uso de los recursos naturales la zona. Este trabajo examina el comportamiento morfodinamico de un sector del frente deltaico del Parana entre el rio Lujan y el San Antonio; con el objetivo estudiar los cambios morfologicos recientes y sus rasgos dinamico-sedimentarios asociados. Los resultados obtenidos muestran que el frente deltaico ha tenido un avance episodico relacionado con la incorporacion y adosamiento de barras de desembocadura en la boca de los canales distributarios, incrementando la superficie y extension de la planicie deltaica inferior. Se han adosado tres barras de desembocadura desde 1933, correspondientes las decadas 1960, 1980 y 200...
Fil: Tedesco, Ana Maria. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departa... more Fil: Tedesco, Ana Maria. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ciencias Geologicas; Argentina;
Wet-meadows are wetlands of high environmental value and common in the Patagonia, Cordillera de l... more Wet-meadows are wetlands of high environmental value and common in the Patagonia, Cordillera de los Andes and Pampean Ranges of Argentina. Particularly, the studies about the functioning and dynamics of wet-meadows are still insufficient and partials in Pampean Ranges. In this paper we analyze the geological-geomorphological factors that influenced the origin, distribution, morphometry and dynamics of wet-meadows in highlands of the southern Comechingones Range (Pampean Ranges of Córdoba, Argentina). A paleoenvironmental reconstruction from sedimentological, palynological, diatomological and chronological records of one of these systems is also proposed. The study area is located at an erosion paleosurface developed previously to the andean orogeny, on an igneous-metamorphic basement rocks. This paleosurface is preserved in the eastern slope of the Comechingones Range and shows different degree of fluvial incision. Most wetmeadows are linked to geomorphological environments with low...
Marine Isotope Stage 3 (MIS 3) is characterized by high climatic variability resulting from numer... more Marine Isotope Stage 3 (MIS 3) is characterized by high climatic variability resulting from numerous centennial to millennial scale events. The environmental and climatic reconstruction of this interval is restricted by the sparsity of high-resolution (centennial-scale) terrestrial records in most of South America. This contribution is an attempt to reconstruct the general environmental and climatic conditions of southern South America during MIS 3 by means of continental records located in central Argentina; this is an extensive and heterogeneous region made up of diverse geomorphological settings under different climatic conditions. Therefore, the main features of several aeolian and fluvial records situated in different geomorphological settings across the region are overviewed. The results indicate the predominance of regional aggradation during MIS 3 with differences in the accumulation rates and dominance of either aeolian or fluvial deposits depending on the geomorphological setting. The aggradation process was interrupted by stability intervals evidenced by paleosols in the San Rafael plain, the San Luis paleo-dunefield, the eastern Sierras Pampeanas piedmont and the eastern Pampean plain. The paleosols might represent lapses of decreasing aeolian input and perhaps more humid conditions. In addition, paleobiological indicators from alluvial sequences suggest higher temperatures and water availability between 35 and 31 ka in the Andean piedmont, while dry subhumid or strongly seasonal conditions with alternating subhumid-humid phases were inferred in the eastern Pampean plain during MIS 3. These intervals tend to cluster during the second part of MIS 3, and might reflect the environmental responses to some of the climatic oscillations that occurred during MIS 3. Detailed analysis and a more adjusted chronology are needed to correlate the aeolian and fluvial episodes along with the stability intervals at regional and continental scales.
The sanrafaelina plain is covered by aeolian and fluvial deposits, the former comprise, in some c... more The sanrafaelina plain is covered by aeolian and fluvial deposits, the former comprise, in some cases, large dune fields while the latter are associated to permanent and ephemeral rivers that drain this plain. The drainage network is made up of two main rivers (Diamante y Atuel) together with smaller, semipermanent or temporary, streams. Two of these streams, Agua del Chancho and La Hedionda creeks, are located in a transitional zone between a fluvially-dominated plain to the south (Diamante river plain) and an aeolian-dominated area to the north (Médanos de los Naranjos dune field). In this region three geomorphic units were recognized: a regional aggradational plain (sanrafaelina plain) and within the creek valleys a fill terrace and the present floodplain of the streams. These units are mainly composed of silty sands with a variable presence of gravel levels. Sedimentological analysis in the aggradational plain allowed to differentiate fluvial and aeolian-fluvial deposits at the ...
En los últimos años el delta del Paraná ha recibido una atención creciente de distintos profesion... more En los últimos años el delta del Paraná ha recibido una atención creciente de distintos profesionales, debido al rápido crecimientopoblacional de las islas del Tigre y de los municipios de San Isidro y San Fernando. Este hecho incrementó el valor económico eintensificó el uso de los recursos naturales en la zona. Este trabajo estudia el comportamiento del sector sureste del frente deltaicodel Paraná entre los años 1933 y 2016; con el objeto de registrar los cambios morfológicos recientes y sus rasgos dinámico-sedimentarios asociados. Los resultados obtenidos muestran que el frente deltaico ha tenido un avance episódico relacionado el adosamientode barras de desembocadura en la boca de los canales distributarios, incrementando la superficie y extensión de la planicie deltaicainferior. Estas barras se adosaron en las décadas 1935-50, 1960, 1980 y 2000. La velocidad de avance del frente deltaico varió de42,30 m/año a 45,13 m/año. Esta rápida progradación ha producido cambios naturales ...
Supplemental material, Supplementary_Material,_Table_B for Human occupation strategies and relate... more Supplemental material, Supplementary_Material,_Table_B for Human occupation strategies and related environmental-climate during the middle and late Holocene in central Pampas of Argentina by Pablo G Messineo, Marcela S Tonello, Silvina Stutz, Alfonsina Tripaldi, Nahuel Scheifler, Nélida Pal, Guillermina Sánchez Vuichard and Diego Navarro in The Holocene
En los ultimos anos el delta del Parana ha recibido una atencion creciente de geologos, biologos,... more En los ultimos anos el delta del Parana ha recibido una atencion creciente de geologos, biologos, arquitectos y planificadores ambientales debido al rapido crecimiento poblacional de las islas del Tigre y de los Municipios de San Isidro y San Fernando. Este hecho ha incrementado el valor economico de estos territorios e intensificado el uso de los recursos naturales la zona. Este trabajo examina el comportamiento morfodinamico de un sector del frente deltaico del Parana entre el rio Lujan y el San Antonio; con el objetivo estudiar los cambios morfologicos recientes y sus rasgos dinamico-sedimentarios asociados. Los resultados obtenidos muestran que el frente deltaico ha tenido un avance episodico relacionado con la incorporacion y adosamiento de barras de desembocadura en la boca de los canales distributarios, incrementando la superficie y extension de la planicie deltaica inferior. Se han adosado tres barras de desembocadura desde 1933, correspondientes las decadas 1960, 1980 y 200...
Fil: Tedesco, Ana Maria. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departa... more Fil: Tedesco, Ana Maria. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Ciencias Geologicas; Argentina;
Wet-meadows are wetlands of high environmental value and common in the Patagonia, Cordillera de l... more Wet-meadows are wetlands of high environmental value and common in the Patagonia, Cordillera de los Andes and Pampean Ranges of Argentina. Particularly, the studies about the functioning and dynamics of wet-meadows are still insufficient and partials in Pampean Ranges. In this paper we analyze the geological-geomorphological factors that influenced the origin, distribution, morphometry and dynamics of wet-meadows in highlands of the southern Comechingones Range (Pampean Ranges of Córdoba, Argentina). A paleoenvironmental reconstruction from sedimentological, palynological, diatomological and chronological records of one of these systems is also proposed. The study area is located at an erosion paleosurface developed previously to the andean orogeny, on an igneous-metamorphic basement rocks. This paleosurface is preserved in the eastern slope of the Comechingones Range and shows different degree of fluvial incision. Most wetmeadows are linked to geomorphological environments with low...
VII International Conference Aeolian Research, 2010
Landscapes of western Argentina present several dune fields, many of them partially enclosed by h... more Landscapes of western Argentina present several dune fields, many of them partially enclosed by high ranges of the Andean domain. Médanos Grandes (MG) dune field (San Juan province) is bounded by the Sierra de Pie de Palo to the north, a high massif of Precambrian-Lower Paleozoic metasedimentary and metavolcanic rocks. Colluvial and fluvial deposits occur along the east, west and southern margins (Bermejo and San Juan River plains). To the northeast there is the Sierra de Valle Fértil, mostly composed of Precambrian-Lower Paleozoic metasedimentary rocks, some non- to strongly metamorphosed, mafic to acid igneous rocks and a sedimentary cover. Other important sediment sources are the Andes (Upper Paleozoic granites and sedimentary and volcanic successions of very variable ages), and the Precordillera (Paleozoic and Cenozoic sedimentary rocks with minor Upper Paleozoic volcanites). Two sets of samples from MG were petrographically studied. The first is middle to late Holocene aeolian sand that corresponds to litharenites to feldspathic litharenites, with metamorphic and volcanic lithics and lesser amounts of quartz and feldspar. The second group (samples from less than 10 cm deep digs, non-dated but likely younger than 100 year old aeolian sand) includes lithic feldsarenites to feldspathic litharenites, with higher amounts of quartz and feldspars. Although the tectonic environment of the source areas has not varied in the Holocene, the two groups show compositional differences reflected, among others, in the QFL ratio. The Holocene sand portrays a provenance from undissected to transitional arc, whereas the present sand samples plot in the dissected arc field. This difference reflects a multiple and changing sediment sources due to the aeolian reworking of the Bermejo and San Juan River plains that collect volcanic-sedimentary and crystalline basement detritus.
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