Deep submarine landslide contribution to the 2010 Haiti earthquake tsunami
<p>The devastating <span class="inline-formula"><i>M</i><sub>w</sub></span> 7.1 Haiti earthquake in 2010 was accompanied by local tsunamis that caused fatalities and damage to coastal infrastructure. Some were triggered by slope failures of river d...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2020-07-01
|
| Series: | Natural Hazards and Earth System Sciences |
| Online Access: | https://nhess.copernicus.org/articles/20/2055/2020/nhess-20-2055-2020.pdf |
| Summary: | <p>The devastating <span class="inline-formula"><i>M</i><sub>w</sub></span> 7.1 Haiti earthquake in 2010 was
accompanied by local tsunamis that caused fatalities and damage to coastal
infrastructure. Some were triggered by slope failures of river deltas in the
close vicinity of the epicenter, while others, 30 to 50 km to the north
across the Bay of Gonâve, are well explained by the reverse component of
coseismic ground motion that accompanied this mostly strike-slip event.
However, observations of run-up heights up to 2 m along the southern coast
of the island at distances up to 100 km from the epicenter, as well as tide
gauge and DART buoy records at distances up to 600 km from the epicenter,
have not yet received an explanation. Here we demonstrate that these
observations require a secondary source, most likely a submarine landslide.
We identify a landslide scar 30 km from the epicenter off the southern coast
of Haiti at a depth of 3500 m, where ground acceleration would have been
sufficient to trigger slope failure in soft sediments. This candidate
source, 2 km<span class="inline-formula"><sup>3</sup></span> in volume, matches observations remarkably well assuming
that the sediment collapse obeys a viscous flow with an initial apparent
viscosity of <span class="inline-formula">2×10<sup>5</sup></span> Pa s. Although that particular source
cannot be proven to have been activated in 2010, our results add to a line
of evidence that earthquake-triggered submarine landslides can cause
significant tsunamis in areas of strike-slip tectonic regime.</p> |
|---|---|
| ISSN: | 1561-8633 1684-9981 |