Magnetostratigraphy, magnetoclimatology and environmental magnetism in a Pleistocene sedimentary sequence, Marcos Paz, Argentina

Late Cenozoic sediments exposed in a quarry in the locality of Marcos Paz (Buenos Aires province) were studied by applying paleomagnetism and environmental magnetism. The whole sequence, with the exception of the recent soil, belongs to the Pleistocene and is integrated by clayey silts (sandy) and also by a layer of fine sand. Eleven different depositional/postdepositional units, numbered in descending order from unit 1 to 11, were determined. The units 1, 2 and 3 in the upper portion of the geological section should be assigned to Brunhes (0.78 Ma). Matuyama magnetozone includes some subzones of normal polarity that should be assigned to the subchron Jaramillo (0.99 Ma) and to the subchron Olduvai (1.9 Ma). The reverse polarity levels determined at the bottom of the profile should be assigned to the lower Matuyama (>1.9 Ma). The highest volume susceptibility values are recorded in the less pedogenized sediments (400 x10-5), while the lowest values are always obtained in gleyed horizons (30 x10-5). The data support the wind-vigor magnetoclimatological model, although affected by different pedogenesis degrees and weathering as demonstrated by the behavioral pattern of chemical elements.Fil: Bidegain, Juan Carlos. Provincia de Buenos Aires. Gobernacion. Comision de Investigaciones Cientificas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; ArgentinaFil: Jurado, S.. Provincia de Buenos Aires. Gobernacion. Comision de Investigaciones Cientificas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; ArgentinaFil: Chaparro, Marcos Adrián Eduardo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fi­sica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil; ArgentinaFil: Gómez Samus, Mauro Leandro. Provincia de Buenos Aires. Gobernacion. Comision de Investigaciones Cientificas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil; ArgentinaFil: Zicarelli, S.. Provincia de Buenos Aires. Gobernacion. Comision de Investigaciones Cientificas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; ArgentinaFil: Parodi, A. V.. Provincia de Buenos Aires. Gobernacion. Comision de Investigaciones Cientificas. Laboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológica; Argentin