Magnetostratigraphy and magnetic susceptibility of the Las Carreras loess–paleosol sequence in Valle de Tafı́, Tucumán, NW-Argentina

摘要: Abstract Stratigraphic studies on loess deposits in the intramontane basin of Valle de Tafi (27°S, 66°W) revealed up to 31 intercalated paleosols. In order clarify chronostratigraphic position sediments, we performed paleomagnetic investigations 50-m-thick Las Carreras section. The characteristic remanent magnetization (ChRM) obtained after alternating field (AF) demagnetization gives clear evidence Matuyama-Brunhes boundary (MBB) at a profile depth 26.7 m , and Jaramillo subchron depths from 38.7 44.9 . We assign minimum age 1.15 Ma onset sedimentation, which calls for complete reassessment antiquity region. Thus, sequence, is probably continuous complete, represents one longest Quaternary terrestrial paleoclimatic records reported southern hemisphere. magnetic susceptibility signal follows behavior known Argentinian eolian sediments — though with certain restrictions an overall weak correlation pedostratigraphy. This opposite pattern Chinese Loess Plateau (CLP) seems be influenced strongly by changing source materials contributing Tafi.