Estudios paleoambientales en lagos volcánicos en la Región Volcánica de Pali Aike, sur de Patagonia (Argentina): palinología

Resumen

Palaeoenvironmental studies of crater lakes in the Pali Aike Volcanic Field, southern Patagonia (Argentina): palynology. Sedimentary records from crater lakes are of major scientific interest because they provide continuous high-resolution paleoclimatic and paleoenvironmental archives. For the first time a limnogeological and palynological survey of crater lakes was performed in the Pali Aike Volcanic Field (52°S, southeastern Santa Cruz, Argentina). Studied lakes of the Patagonian steppe are mostly shallow and consist of old and already sediment-filled volcanic structures or of deflation pans. However, bathymetric measurements revealed two deep crater lakes: Laguna Azul (50 m) and Laguna Potrok Aike (100 m) which may serve as archives for paleoecological studies. Although modern pollen spectra are related with vegetational and the precipitation gradients from the Andes to Atlantic coast, the modern pollen spectra of both lakes revealed the change of plants communities in each geomorphological unit. The first approach between modern pollen data and fossil material from the fine-grained sediments of both lakes we are able to interpret environmental and climatic variations during the last 2,000 years as well as human influence for the last two centuries.