Aspectos geomorfológicos y sedimentológicos del Bajo del Durazno, Departamento Loventué, Provincia de La Pampa.

MEHL, ADRIANA E.; ZÁRATE, MARCELO A.

Facultad de Ciencias Exactas, Físicas y Naturales, UNC

Congreso; III Congreso Argentino de Cuaternario y Geomorfología; 2006

Asociación Argentina de Cuaternario y Geomorfolgía

Bajo del Durazno, situated in the central eastern part of La Pampa province (65º10' - 65º30'W,36º33' - 36º45'S) is a closed drainage system associated with a regional longitudinal depression. This depression along with several other depressions known as Valles transversales (Transverse valleys) runs across an extensive structural plain. Bajo del Durazno has been excavated into late Miocene sandy silts capped by a thick calcrete crust (Cerro Azul Formation). The internal relief of the geoform is characterized by a stepped topography composed of three main elevation systems and a very low relief plain in the deepest part.. The topographic elevations are composed of sandy silts and gravel layers made up of carbonate fragments derived from the erosion of the calcrete crust and the carbonate nodules of the late Miocene deposits. This unit crops out in the western and the southern rim of the depression. The plain of the deepest part consists of sandy silts with blocky structure. An eolian mantle of sandy deposits was accumulated in the late Pleistocene-Holocene, blanketing the different units identified. Geomorphologically at a local scale, the landscape of Bajo del Durazno reproduces a piedmont system resulting from at least 4 main degradation-aggradation cycles. No information was recovered to calibrate the chronology of these cycles which occurred sometime during the late Miocene-Pleistocene interval.