Investigator:

Wendy DeWolf

Advisor: Mark Brandon

Description:

We live in a warm interglacial world, where we see deep U-shaped valleys but not the large glaciers that cut them. We tend to think that alpine glaciers that formed as the global temperature cooled over the last several million years carved these landscapes. In the Central Patagonian Andes, however, there is evidence of alpine glaciers dating back to at least 6 million years, when the prevailing global climate was still warm. Recent work on glacial modeling suggests that the earliest glaciations in the Patagonian Andes occurred 6 Ma. As of yet, we do not know how these early glaciations altered the landscape.

Our goal is to determine whether the glacial valleys in Patagonia have been carved quickly over the colder conditions of the last 2 millions years or more slowly starting with the early glaciations at 6 Ma when the climate was warmer. We will determine when and at what rate these glacial valleys were cut using a radiometric dating technique called (U-Th)/He thermochronology. Using ArcGIS, we will perform analysis of our data set in context of the modern topography. This work has important implications for our understanding of the feedback between climate change and glacial erosion, as well as our understanding of how glaciers control the height and shape of mountains.