105 D9. Recent Advances in Geomorphology (Posters)

Monday, 23 September 2019
9:00 AM - 6:30 PM
Hall AB, North Building

GSA QUATERNARY GEOLOGY AND GEOMORPHOLOGY DIVISION ARTHUR D. HOWARD AWARD: IMPACTS OF RAPID CLIMATE WARMING ON THE FREQUENCY AND SPATIAL DISTRIBUTION OF LANDSLIDES IN A SUBARCTIC MOUNTAIN RANGE, DENALI NATIONAL PARK AND PRESERVE, ALASKA

Paper number: 105-7
Program: Technical Sessions
Time: 9:00 AM – 6:30 PM

Authors

Abstract

Denali National Park and Preserve (DENA) is a crown jewel within the US National Park system. It receives over 600,000 visitors a year, most of whom travel the 140-km road traversing the northern flank of the park. This road is increasingly threatened by a wide range of mass movement types, some of which are related to the thawing of permafrost, or perennially frozen ground, as climate warms. Landslides along the DENA road corridor are both an urgent management issue and an interesting case study into how climate change impacts hillslope geomorphology in a subarctic mountain range. We hypothesize that mass movements in DENA have increased in frequency because of post-Little Ice Age warming, and further that landslides are most frequent on north-facing slopes because active layers (depth of seasonal freeze-thaw) are thinnest there and have been less affected by past climatic fluctuations. To test these hypotheses, we classified mass movements using the Varnes system modified for periglacial environments, mapped their occurrence in a GIS database to test for differences in aspect frequency, and used remote sensing imagery and lichenometry to estimate initial failure dates. Preliminary results confirm that landslide frequency has increased over the last several decades, corroborate observations that permafrost thaw is frequently involved in landslide initiation, and suggest that slope aspect is a useful predictor of landslide occurrence.

Geological Society of America Abstracts with Programs. Vol. 51, No. 5

doi: 10.1130/abs/2019AM-337290

© Copyright 2019 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.