Big Tsunamis in Little Lakes
The past decade has seen a spate of dramatic tsunamis, largely going unnoticed, triggered by landslides into small water bodies. This presentation will explore examples since 2016 in British Columbia and Alaska, including those listed below:
Location Date Landslide volume (Mm3) Maximum runup (m)
Cowee Creek 30 Dec 2016 0.5 ?
Elliot Creek 28 Nov 2020 18 > 100
Brabazon Range ~12 Aug 2021 ~10 ~30
Upper Pederson Lagoon 15 Apr 2022 ~1 ~7
Ecstall River 1 Sep 2022 5+ ?
Some of these events resulted from landslides that produced distinctive seismic signals, but in only some of these cases was this seismic signal automatically characterized as a landslide. These went unnoticed until later, when their dramatic impacts were discovered by locals or through examining satellite imagery. Comparing the events reveals patterns that could inform mitigation strategies, including assessment, targeted seismic monitoring, and probabilistic hazard mapping. Fortunately, these recent events have had only minimal human impact. However, there are several sites with dramatic signs of slope instability above lakes fringed with human infrastructure and popular with visitors. It’s critical that we improve assessment, planning, and monitoring related to these hazards before we have the benefit of tragic hindsight.
Session: Detecting, Characterizing and Monitoring Mass Movements - III
Type: Oral
Room: Kahtnu 2
Date: 5/2/2024
Presentation Time: 03:00 PM (local time)
Presenting Author: Bretwood Higman
Student Presenter: No
Additional Authors
Bretwood Higman Presenting Author Corresponding Author hig314@gmail.com Ground Truth Alaska |
Ezgi Karasozen ekarasozen@alaska.edu Alaska Earthquake Center |
Marten Geertsema marten.geertsema@gmail.com Ministry of Forests, Lands and Natural Resource Operations |
Susan Schwartz syschwar@ucsc.edu University of California, Santa Cruz |
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Big Tsunamis in Little Lakes
Category
Detecting, Characterizing and Monitoring Mass Movements
Description