The ground motion produced by the 2010 Haiti earthquake — in combination with quake-triggered coastal landslides — generated several small tsunamis, according to a study published online this week in Nature Geoscience. Strike-slip fault systems, such as the one that runs through Haiti, are not usually associated with tsunamis.
Using geologic field data and images of the ocean floor, Matthew Hornbach and colleagues documented only modest uplift of the ground surface that would not usually be sufficient to generate a tsunami. However, they found that the earthquake also caused several submarine landslides, which, together with the ground motion, resulted in the production of local tsunamis.
The researchers conclude that the coastal setting and high sedimentation rates in this region probably cause landslide-generated tsunamis much more frequently in Haiti than previously predicted. This paper is one of the first two to be published this month as part of Nature Geoscience’s special issue on the Haiti earthquake.