Preliminary Rock Magnetic and Paleoenvironmental Studies of Short Sediment Cores from Laguna Potrok Aike (Santa Cruz, Argentina)

C. S. G. GOGORZA; A. M. SINITO; CARLOS VASQUEZ; KASTNER, S.; C. OLHENDORF; B. ZOLITSCHKA

Tandil

Congreso; Segunda Reunión Bienal de la Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo (LatinMag).; 2011

LatinMag/UNCPBA

We report rock magnetic and magnetic mineralogy results of a preliminary study carried out for five sediment cores recovered from the maar lake laguna Potrok Aike (Patagonia, Argentina). This investigation contributes to a better understanding of the processes related to paleoclimatic andpaleoenvironmental changes that occurred in the southern Patagonian steppe during the last ~700 years. In order to characterize the magnetic mineralogy, detailed magnetic measurements were made to investigatethe response of the sediments to a variety of applied magnetic fields. This response is mainly determined by the mineralogy, concentration, and grain-size distribution of the magnetic phases. Rock magnetic properties document that main carriers of magnetization are ferrimagnetic minerals, predominantlypseudo-single domain (PSD) magnetite. Intervals of different magnetic content could be related to fluctuations in the lake level that can be associated with climatic variations.