ABSTRACT

The Argentine-Polish Paleolimnological Project in the S extreme of South America (1987) aimed to contribute to the paleoenvironmental and paleoclimatic knowledge of one of Tierra del Fuego vast lacustrine areas. The Lago Yehuin zone was chosen because it is comprised in one of the water basins originated during ice recession during the last glaciation. Several bottom-lake and old terrace sedimentary cores were obtained using “boomerang” and drilling methods. The analysis of collected material and field observations yield a preliminary interpretation of the events. During the Holocene, several events took place: a) drainage inversion of Lago Yehuin; b) remarkable lowering of the level of the deepest lakes during the last glaciations; c) biota expansion and the development of peat bog areas; d) growth of the adequate vegetation for the Holocene ecological conditions, such as Nothofagus antarctica and Nothofagus pumilio forests.