%0 Journal Article
%T Aspectos sedimentol車gicos de arenas e車licas del Pleistoceno tard赤o-Holoceno de la provincia de La Pampa Sedimentologic aspects of eolian sands from the Late Pleistocene-Holocene of the La Pampa Province
%A Manuel Szelagowski
%A Marcelo A Z芍rate
%A Adriana M Blasi
%J Revista de la Asociaci車n Argentina de Sedimentolog赤a
%D 2004
%I 
%X El objetivo general de este trabajo es analizar la procedencia, g谷nesis y din芍mica de transporte de los dep車sitos e車licos arenosos del centro-este de la provincia de la Pampa. Para ello, se analizaron el marco geol車gico-geomorfol車gico y los aspectos estratigr芍ficos de tres sectores considerados como sendos estudios de casos: cord車n medanoso La Pastoril-Santa Isabel, cord車n medanoso Toay y cord車n medanoso General Acha. Estos cordones se caracterizaron sedimentol車gicamente (granulometr赤a, mineralog赤a) a trav谷s del an芍lisis de 20 muestras. Se identificaron dos unidades e車licas asociadas a dos ciclos de sedimentaci車n, informalmente denominadas inferior (Pleistoceno tard赤o-Holoceno medio) y superior (originado por acci車n antr車pica durante el siglo XX) relacionados con vientos del cuadrante O-NO en Santa Isabel y del S y SO en General Acha. Los resultados obtenidos sugieren que la topograf赤a ser赤a un factor de control importante en la distribuci車n de los sedimentos, adem芍s de la distancia al sistema fluvial, que determinar赤a su tama o de grano. Los an芍lisis mineral車gicos indicar赤an un aporte mixto de materiales, tanto distal (sistema fluvial del Bermejo-Desaguadero-Salado-Curac車), como local (afloramientos rocosos de la provincia). The main goal of this paper is to analyze the provenience of sandy eolian deposits of the central eastern part of La Pampa Province. Considering present eolian models proposed by different authors, the hypothesis tested in this paper is that eolian sediments are the result of deflation of alluvial deposits from the Bermejo-Desaguadero-Salado-Curac車 fluvial system. With this purpose in mind, three case studies were selected (La Pastoril-Santa Isabel, Toay and General Acha) (Fig. 1). The analysis was made following the concept of spatial scale hierarchy which considered the geological and general environmental setting of the studied areas along with fundamental geomorphological features of the analyzed dune systems. This was complemented by the stratigraphic survey of selected sections from which 20 samples were collected for sedimentological analysis (grain-size and mineralogy). Also, due to the lack of information, three samples were collected from the present Desaguadero fluvial system for general characterization. At the regional scale two main geoforms were identified: an extensive plain and the paleovalley of the Desaguadero fluvial system. The plain grades eastward and includes several longitudinal depressions (longitudinal valleys). A sandy silt mantle is covering the plain, whereas the main dune system is located along the lo
%K Cuaternario
%K La Pampa
%K E車licos
%K M谷danos
%K Quaternary
%K La Pampa
%K Eolian deposits
%K Dunes
%U http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1853-63602004000200004