The Local Last Glacial Maximum along the Patagonian Andes: a composite geographic, geochronologic and modeling approach
Abstract
In order to understand the mechanisms underlying the climate cycles that have punctuated the Quaternary period, we need to unravel the geographical extent and test for interhemispheric phasing of glacial events. New glacier records from southern Patagonia suggest that maximum glacial extent during the last glacial cycle occurred sometime during the Marine Isotope Stage (MIS) 3. In this context, new data from the southern mid-latitudes in Patagonia, and New Zealand, reaffirm the important unsolved question regarding the timing, structure and duration of the local glacial maximum in the southern mid-latitudes: When did the local glacial maximum occur in the region? Why have only scattered sites in Patagonia revealed glacial expansion during MIS 3? Is the new glacier evidence from these scattered southern Patagonian sites a local anomaly or have we not yet completely unraveled the complete configuration of the southern Andean LGM? In this regard, the main goal of the research project is to determine the timing of the local last glacial maximum along the Patagonian Andes (43-55ºS). In order to accomplish this objective the proposed research includes the following interconnected approaches: glacial geomorphology, glacial stratigraphy, geochronology and glacial modeling. By selecting sites along a latitudinal transect we aim to include the latitudinal as well as the local factors that may control the Patagonian glaciation. We address this issue by applying a 3D Parallel Ice Sheet Model (PISM), constrained by precise mapping and well-dated glacial landforms. We will apply 10Be exposure-cosmogenic dating on boulders resting on moraines, OSL and 10Be dating in glaciofluvial sediments. We expect our composite approach will allow us to bracket the timing of the local LGM extent in Patagonia and thereby test for regional, hemispherical and global phasing of maximum glaciation during the last ice age.
Chile Patagonia Andes Glacial Cycles Last Glacial Maximum
Publikationen
Project staff
Christopher Lüthgens
Assoc. Prof. Dr. Christopher Lüthgens
christopher.luethgens@boku.ac.at
Tel: +43 1 47654-87213
BOKU Project Leader
15.11.2017 - 14.11.2021
BOKU partners
External partners
Pontifical Catholic University of Chile
Juan Luis Garcia (PhD)
partner