Latest Pleistocene glacial chronology and paleoclimate reconstruction for the East River watershed, Colorado, USA

Reconstructing Pleistocene glaciation timing and extent is vital for understanding paleoclimate. Whereas late Pleistocene glaciation has been studied extensively in western North American mountain ranges, the glacial history of the western Elk Range in Colorado remains understudied, particularly in the East River watershed, a site of intense scientific focus. Here we use cosmogenic nuclide exposure and depth–profile dating methods to determine the timing of glaciation in the East River watershed. We use glacier modeling to reconstruct paleoglacier extents and quantify past climate conditions. Our findings indicate that the East River glacier retreated from its maximum position approximately 17–18 ka, moving to recessional positions between 13 and 15 ka, before experiencing more substantial retreat to high-elevation cirques around 13 ka. Glacier modeling suggests that the maximum ice extents at 17–18 ka could have been sustained by temperature depressions of approximately −6.5°C compared to modern conditions, assuming consistent precipitation. Additionally, the ice position at 13–15 ka could have been supported by temperature depressions of around −4.0°C. These results offer insights into the deglaciation timeline in the East River watershed and broader western Elk Range as well as paleoclimate conditions during the late Pleistocene, which may aid future research on critical zone evolution in the East River watershed.

Chronology · Climate change · Cosmogenic nuclide · Deglaciation · Geography · Geomorphology · Glacial period · Glacier · Ice sheet · Last Glacial Maximum · Moraine · Paleoclimatology · Physical geography · Pleistocene · Surface exposure dating · Watershed · Climate change and permafrost · Cryospheric studies and observations · Geology · Geology and Paleoclimatology Research · Oceanography · Paleontology

• Accuracy of cosmogenic ages for moraines

  Open Access•Jaakko Putkonen, Terry W Swanson et al.•Quaternary Research•2003

  Añadir item

• Cosmogenic 10 Be exposure dating of Bull Lake and Pinedale moraine sequences in the upper Arkansas River valley, Colorado Rocky Mountains, USA

  Open Access•A D Schweinsberg, Jason P Briner et al.•Quaternary Research•2020

  Añadir item

• Improved moraine age interpretations through explicit matching of geomorphic process models to cosmogenic nuclide measurements from single landforms

  Open Access•Patrick J Applegate, Nathan M Urban et al.•Quaternary Research•2012

  Añadir item

• Physiographically sensitive mapping of climatological temperature and precipitation across the conterminous United States

  Open Access•Christopher Daly, Michael Halbleib et al.•International Journal of…•2008

  Añadir item

• A complete and easily accessible means of calculating surface exposure ages or erosion rates from 10Be and 26Al measurements

  Open Access•Greg Balco, John O Stone et al.•Quaternary Geochronology•2008

  Añadir item

• The Last Glacial Maximum

  Open Access•Peter U Clark, Arthur S Dyke et al.•Science•2009

  Añadir item

• Extracting a Climate Signal from 169 Glacier Records

  Open Access•J Oerlemans, J J Oerlemans•Science•2005

  Añadir item

• Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum

  Open Access•Keith A Brugger, Eric M Leonard et al.•Quaternary•2021

  Añadir item

• Climate during the Last Glacial Maximum in the Northern Sawatch Range, Colorado, USA

  Open Access•Keith A Brugger, Chester A Ruleman et al.•Quaternary•2019

  Añadir item

• Little Ice Age glaciers in Britain

  Open Access•Stephan Harrison, Ann V Rowan et al.•The Holocene•2013

  Añadir item