Why didn't the earthquake cause a tsunami?
Strike-slips faults like the one that devastated Haiti don't generally cause tsunami, except for small local ripples. The Haiti earthquake was a horizontal motion. Tsunamis are caused by either an uplifting of the ocean floor, or by a huge chunk of land sliding into the ocean. Subduction-zone earthquakes raise the ocean bottom suddenly to push the water in tsunamis.
The beach of a small fishing town was hit by a localised tsunami shortly after the earthquake, as a result of an underwater slide, At least three people were swept out to sea by the wave and were reported dead.
- The tectonic plates in Haiti are moving horizontally past one another.
- The largest tsunamis are caused by vertical motion of the land.
- Vertical rebound in subduction zones push the water up into a tsunami.