The Continental Record of Marine Isotope Stage 3 (MIS 3; -60-25 ka) in Central \rgentina: Evidence from Fluvial rnd Aeolian Sequences

ADRIANA MEHL; ALFONSINA TRIPALDI; MARCELO ZÁRATE

MArine isotope stage 3 in southern South America 60 BP ka-30 ka BP

SPRINGER NETHERLANDS

Año: 2016; p. 167 - 181

-:*tract Marine Isotope Stage 3 (MIS 3) is characterized by high climatic vari-. , resulting from numerous centennial to millennial scale events. The envi-´ - :rtal and climatic reconstruction of this interval is restricted by the sparsity of-´-::solution (centennial-scale) terrestrial records in most of South America. This´-rution is an attempt to reconstruct the general environmental and climatic ´- ..ons of southenr South America during MIS 3 by means of continental-:. located in central Argentina; this is an extensive and heterogeneous region-,: ,p of diverse geomorphological settings under different climatic conditions.´.:.re. the main features of several aeolian and fluvial records situated in dif-" . _ieomorphological settings across the region are overviewed. The results. .-: the predominance of regional aggradation during MIS 3 with differences in ´ --,-umulation rates and dominance of either aeolian or fluvial deposits´ :´lrog on the geomorphological setting. The aggradation process was inter-: - r stability intervals evidenced by paleosols in the San Rafael plain, the San. :leo-dunefield, the eastem Sierras Pampeanas piedmont and the eastern:::n plain. The paleosols might represent lapses of decreasing aeolian input,-E:raps more humid condilions. In addition, paleobiological indicators from- sequences suggest higher temperatures and water availability between 35´ ka in the Andean piedmont, while dry subhumid or strongly seasonal- ns with alternating subhumid-humid phases were inferred in the eastern-::: plain during MIS 3. These intervals tend to cluster during the second parl.> -1. and mieht reffect the environmental resoonses to some of the climatic