Department of Physical

Periglacial and glacial mapping in the Las Veguitas catchment, Cordillera Frontal of the ()

Eirini Makopoulou

Master’s thesis NKA 211 and Quaternary Geology, 60 Credits 2018


This Master’s thesis is Eirini Makopoulou’s degree project in Physical Geography and Quaternary Geology at the Department of Physical Geography, Stockholm University. The Master’s thesis comprises 60 credits (two terms of full-time studies).

Supervisors have been Peter Kuhry at the Department of Physical Geography, Stockholm University and Dario Trombotto at the Geocryology, CONICET, Mendoza (Argentina). Examiner has been Johan Kleman at the Department of Physical Geography, Stockholm University.

The author is responsible for the contents of this thesis.

Stockholm, 12 June 2018

Lars-Ove Westerberg Vice Director of studies


The semi-arid and arid Andes of are characterized by large areas with glacial and periglacial environments. This study focusses on the distribution of glacial and periglacial in the Las Veguitas catchment, Cordillera Frontal, Argentina. A detailed geomorphological map of the Las Veguitas catchment is presented, based on high-resolution elevation data (ALOSPALSAR), satellite imagery (Landsat 8, World View 2, Google ), and field studies. First, a general topographical analysis is performed for the entire Las Veguitas catchment, including elevation, slope and aspect characteristics. Second, the altitudinal range of glacial features (, debris covered glaciers and on glaciers) and the altitudinal range and predominant aspect of periglacial features (active, inactive and fossil rock glaciers) are analyzed. Currently, glaciers are restricted to ≥ 4300m, but are identified to elevations of c. 3200m. Active rock glaciers extend down to c. 3450m and have a more southern aspect then both inactive and fossil rock glaciers. Third, a temporal analysis has been performed of and flow using a time series of images. Glacier flow traced by the displacement of thermokarst features (2006-2016) had a mean velocity of 6.66m/yr. The mean velocity of rock glaciers (1963-2017) was much lower at 0.63m/yr. Finally, the thesis discusses limitations and uncertainties in study methods and suggestions for further research activities.

Keywords: geomorphological map, glaciers, thermokarst , , rock glaciers, Argentinean Andes, remote sensing images, ArcGIS, spatial and temporal analyses


1 Introduction ...... 5 2 Background ...... 7 2.1 The Cordillera de los Andes ...... 7 2.2. Glacial history in the Central Andes ...... 8 2.3 Glacial Processes and landforms ...... 9 2.4 Periglacial Processes and landforms ...... 11 3 Study area...... 15 3.1 Geology ...... 15 3.2 Climate ...... 16 3.3 cover ...... 17 3.4 Permafrost distribution ...... 17 4 Material and Methods ...... 17 4.1 Pre-field preparatory steps ...... 19 4.2 Fieldwork ...... 20 4.3 Final processing ...... 21 4.4 Temporal analysis ...... 22 5 Results ...... 23 5.