Author ORCID Identifier
https://orcid.org/0000-0002-2993-9930
Date of Award
Summer 8-15-2025
Document Type
Thesis (Master's)
Department or Program
Earth Sciences
First Advisor
Justin Strauss
Second Advisor
Marisa Palucis
Third Advisor
Meredith Kelly
Abstract
Rapid warming and permafrost thaw across Arctic landscapes are projected to drastically accelerate local erosion rates and sediment fluxes to downstream systems and the communities that rely on them. However, interpreting this signal of change first requires disentangling the relative contributions of postglacial landscape responses, periglacial processes, and modern warming to observed changes in erosion. To explore this problem, we combine a suite of geochronometers to examine erosion and deposition rates over timescales of 102–107 years across a periglacial alluvial fan and catchment system on the former margin of the Laurentide Ice Sheet in the Aklavik Range of Northwest Territories, Canada. We use low-temperature thermochronology (apatite fission-track and apatite/zircon (U-Th)/He) to constrain the background (~25 Ma) erosion rate of the Aklavik Range at ~0.09 mm/yr. Cosmogenic nuclide (10Be) dating of erratic boulders near the Laurentide glacial limit in the Aklavik Range suggest that the region was last glaciated prior to ~20.3 ka, 1.8 ka earlier than previously thought. Postglacial fan- and catchment-derived erosion rates (~1-7 mm/year), calculated using mass balance, radiocarbon (14C) dating, and optically stimulated luminescence (OSL) dating, exceed background rates by an order of magnitude or more. These results underscore that contributions to observed erosion rates from modern warming must account for persistent postglacial landscape disequilibrium in Arctic ice-marginal settings.
Recommended Citation
Nordin, Bailey J., "Postglacial Erosional Response of a Permafrost Landscape across Decadal to Millenial Timescales, Aklavik Range, Arctic Canada" (2025). Dartmouth College Master’s Theses. 207.
https://digitalcommons.dartmouth.edu/masters_theses/207
