Articulo
Evidence of a possible reversion of the geomagnetic field registered during the late holocene in the province of Chubut, Argentina
Autor
Nami, Hugo G.
Sinito, Ana M.
Institución
Resumen
Paleomagnetic studies were carried out on sediments sampled at an archaeological excavation sited on Angostura Blanca, Piedra Parada Valley, Province of Chubut (42°30'S, 69°42'W). The archaeological traces show the occupation of the site during the late holocene; this is confirmed by the C1 dating of sanóles obtained on the site (2140+50 years). The usual laboratory techniques for paleomagnetic studies were applied to isolate the directions of the stable remanent magnetization (measurements of natural remanent magnetization, demagnetization by increasing temperatures, measurements of residual remanent magnetization after each step of demagnetization). Using the isolated directions, which represent the directions of the geomagnetic field during the deposition and consolidation of the sediments, the virtual geomagnetic poles were obtained. The analysis of the results shows evidence of a possible record of a reversed polarity event on the studied sediments. This conclusion, if it is confirmed by other paleomagnetic data, would agree with the existence of the Etrussia excursion, recorded in Russia, on sediments of about 2700 years. Material digitalizado en SEDICI gracias a la colaboración de la Facultad de Ciencias Astronómicas y Geofísicas (UNLP). Asociación Argentina de Geofísicos y Geodestas