Next Article in Journal
Mapping Archaeology While Mapping an Empire: Using Historical Maps to Reconstruct Ancient Settlement Landscapes in Modern India and Pakistan
Next Article in Special Issue
Assessing Submarine Slope Stability through Deterministic and Probabilistic Approaches: A Case Study on the West-Central Scotia Slope
Previous Article in Journal
Survival of Radioresistant Bacteria on Europa’s Surface after Pulse Ejection of Subsurface Ocean Water
Article Menu
Issue 1 (January) cover image

Export Article

Open AccessArticle
Geosciences 2019, 9(1), 10; https://doi.org/10.3390/geosciences9010010

Seismic Imaging of Seafloor Deformation Induced by Impact from Large Submarine Landslide Blocks, Offshore Oregon

1
School of Earth Sciences, The Ohio State University, Columbus, OH 43210, USA
2
ASEE Postdoctoral Research Fellow, US Naval Research Laboratory, Stennis Space Center, Washington, DC 20375, USA
3
College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA
4
Department of Coastal and Marine Systems Science, Coastal Carolina University, Conway, SC 29528, USA
*
Author to whom correspondence should be addressed.
Received: 13 November 2018 / Revised: 17 December 2018 / Accepted: 19 December 2018 / Published: 25 December 2018
(This article belongs to the Special Issue Submarine Landslides – Assessing the Stability of Submerged Slopes)
Full-Text   |   PDF [8548 KB, uploaded 25 December 2018]   |  

Abstract

A series of large blocks from the 44-North Slide, offshore Oregon, impacted the seafloor with sufficient force to induce a broad zone of deformation. In 2017, we acquired a seismic profile from the headwall area to the outer toe of this slide. Previous work identified this slide, but it has not been imaged at high resolution before this survey. A striking surficial feature is a collection of blocks that lie downslope from an amphitheater-shaped headwall. The blocks traveled up to 20-km horizontally and about 1200-m vertically down a 13° slope and now cover an area of ~100 km2. The blocks have rough and angular edges that extend up to 400-m above the surrounding seafloor. Seaward of the blocks, a 10-km zone of sediment is deformed, horizontally shortened by 8%. We interpret the strain field to be a result of the dynamic impact forces of the slide. This suggests a high-mobility failure with tsunamigenic potential. It is unclear what preconditioned and triggered this event, however, earthquake-induced failure is one possibility. Gas hydrate dissociation may have also played a role due to the presence of a bottom-simulating reflector beneath the source area. This study underscores the need to understand the dynamic processes of submarine landslides to more accurately estimate their societal impacts. View Full-Text
Keywords: submarine landslide; deformation; Cascadia; Oregon; 44-North submarine landslide; deformation; Cascadia; Oregon; 44-North
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Lenz, B.L.; Sawyer, D.E.; Phrampus, B.; Davenport, K.; Long, A. Seismic Imaging of Seafloor Deformation Induced by Impact from Large Submarine Landslide Blocks, Offshore Oregon. Geosciences 2019, 9, 10.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Geosciences EISSN 2076-3263 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top