Controls on Fluvial Geomorphology in the Canadian Rocky Mountains

• Main Author: Quinlan, Kevin
• Other Authors: College of Arts and Sciences, Department of Geological Sciences, Pavelsky, Tamlin, Stewart, Kevin, Willis, Michael
• Format: Master Thesis
• Language: English
• Published: University of North Carolina at Chapel Hill Graduate School 2014
• Subjects: Geomorphology; Geology; Geographic information systems; Geodesy; Schmidt Hammer; Canadian Rocky Mountains; GIS; Fluvial Processes; Erosion; Athabasca River
• Online Access: https://doi.org/10.17615/q1ab-9j95; https://cdr.lib.unc.edu/downloads/j96020977?file=thumbnail; https://cdr.lib.unc.edu/downloads/j96020977

The Canadian Rocky Mountains record a dynamic history of erosion. Presently, bedrock rivers interact with the lithology and structural architecture of a large fold-and-thrust belt. Because the alpine landscape has been modified by Pleistocene and Holocene glaciation, rivers are also influenced by relict glacial landscape features. Here, we use topographic analysis and rock erodibility data to test the impact of lithology and glacial influence on fluvial form and incision potential in the headwaters of the Athabasca River Watershed. For 30 streams, we identify spikes in normalized channel steepness (ksn) where fluvial incision is focused. Results show that proximity to major lithologic contacts is not a predictor of knickzone location. Instead, bedrock channels are most perturbed from equilibrium where they flow over convexities at the intersection between hanging valleys and mainstem valley walls. These results suggest that glacial imprinting--mediated by variations in bedrock geology--controls Holocene erosion in this region. Master of Science