EGU22-10361
https://doi.org/10.5194/egusphere-egu22-10361
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Holocene history of Rio Tranquilo Glacier, Monte San Lorenzo (47°S), Central Patagonia

Esteban Sagredo1,2, Scott Reynhout2,3, Michael Kaplan4, Juan Aravena5, Paola Araya6, Brian Luckman7, Roseanne Schwartz4, and Joerg Schaefer4,8
Esteban Sagredo et al.
  • 1Instituto de Geografía, Pontificia Universidad Católica de Chile. Santiago, Chile
  • 2Núcleo Milenio Paleoclima. Santiago, Chile
  • 3Departamento de Geología, Universidad de Chile. Santiago, Chile
  • 4Lamont-Doherty Earth Observatory, Columbia University. Palisades, NY, United States
  • 5Gaia-Antártica, Universidad de Magallanes. Punta Arenas, Chile.
  • 6Departamento de Geofísica, Universidad de Chile. Santiago, Chile
  • 7Department of Geography and Environment, University of Western Ontario, London, Canada
  • 8Department of Earth and Environmental Sciences, Columbia University. New York, NY, USA

A well-resolved glacial chronology is crucial to compare sequences of glacial/climate events within and between regions, and thus, to unravel mechanisms underlying past climate changes. Important efforts have been made towards understanding the Holocene climate evolution of the Southern Andes; however, the timing, patterns and causes of glacial fluctuations during this period remain elusive. Advances in surface exposure dating techniques, together with the establishment of a Patagonian 10Be production rate, have opened new possibilities for establishing high-resolution glacial chronologies at centennial/decadal scale. Here we present a new comprehensive Holocene moraine chronology from Mt. San Lorenzo (47°S) in central Patagonia, Southern Hemisphere. Twenty-four new 10Be ages, together with three published ages, indicate that the Río Tranquilo glacier approached its Holocene maximum position sometime, or possibly on multiple occasions, between 9860 ± 180 and 6730 ± 130 yr. This event(s) was followed by a sequence of slightly smaller advances at 5750 ± 220, 4290 ± 100 (?), 3490 ± 140, 1440 ± 60, between 670 ± 20 and 430 ± 20, and at 390 ± 10 yr ago. By comparing our results with other glacier chronologies from central and southern Patagonia, we explore the role of the Southern Westerly Winds as a pacemaker of the Holocene glacier fluctuation in southern South America. 

How to cite: Sagredo, E., Reynhout, S., Kaplan, M., Aravena, J., Araya, P., Luckman, B., Schwartz, R., and Schaefer, J.: Holocene history of Rio Tranquilo Glacier, Monte San Lorenzo (47°S), Central Patagonia, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10361, https://doi.org/10.5194/egusphere-egu22-10361, 2022.