Pace and Process of Active Folding and Fluvial Incision Across the Kantishna Hills Anticline, Central Alaska

• Main Authors: Bender, A. M., Lease, R. O., Haeussler, P. J., Rittenour, Tammy M., Corbett, L. B., Bierman, P. R., Caffee, M. W.
• Other Authors: American Geophysical Union
• Format: Text
• Language: unknown
• Published: Hosted by Utah State University Libraries 2019
• Subjects: continental neotectonics; bedrock river incision; luminescence dating; cosmogenic nuclide dating; tectonic geomorphology; Alaska; Earth Sciences; Geology; Physical Sciences and Mathematics; McKinley River; alaska range
• Online Access: https://digitalcommons.usu.edu/geology_facpub/504; https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1503&context=geology_facpub

Rates of northern Alaska Range thrust system deformation are poorly constrained. Shortening at the system's west end is focused on the Kantishna Hills anticline. Where the McKinley River cuts across the anticline, the landscape records both Late Pleistocene deformation and climatic change. New optically stimulated luminescence and cosmogenic 10Be depth profile dates of three McKinley River terrace levels (~22, ~18, and ~14–9 ka) match independently determined ages of local glacial maxima, consistent with climate‐driven terrace formation. Terrace ages quantify rates of differential bedrock incision, uplift, and shortening based on fault depth inferred from microseismicity. Differential rock uplift and incision (≤1.4 m/kyr) drive significant channel width narrowing in response to ongoing folding at a shortening rate of ~1.2 m/kyr. Our results constrain northern Alaska Range thrust system deformation rates, and elucidate superimposed landscape responses to Late Pleistocene climate change and active folding with broad geomorphic implications.