A strong magnitude 6.8 earthquake struck southern Cuba this morning; according to USGS, it followed a strong 5.9 pre-shock and was followed by a 4.6 aftershock. The National Weather Service’s National Tsunami Warning Center in Palmer, Alaska issued an information statement bulletin after the strong earthquake struck. “Earthquakes of this size are known to generate tsunamis dangerous to shorelines near the source,” the National Tsunami Warning Center wrote. “There is no tsunami danger for the U.S. east coast, the Gulf of Mexico states, or the eastern coast of Canada,” the bulletin said.
The 6.8 earthquake struck at 11:50 am today with the pre-shock arriving 1 minute before the the aftershock striking 2 minutes later. More earthquakes are likely in this area in the form of additional aftershocks due to the magnitude of this seismic event.
Most seismic activity in Cuba takes place in the region around Santiago. A fault line runs along the island’s southeastern coast, marking the boundary between the North American plate and the Caribbean plate, according to Cuba’s seismic service.
Tsunamis are giant waves caused by earthquakes or volcanic eruptions under the sea. Out in the depths of the ocean, tsunami waves do not dramatically increase in height. But as the waves travel inland, they build up to higher and higher heights as the depth of the ocean decreases. According to the National Ocean Service, the speed of tsunami waves depends on ocean depth rather than the distance from the source of the wave. According to NOAA, the parent agency over both the National Weather Service and the Tsunami Warning Center, tsunami waves may travel as fast as jet planes over deep waters, only slowing down when reaching shallow waters. While tsunamis are often referred to as tidal waves, tides have little to do with these giant waves. While tsunamis are often referred to as tidal waves, this name is discouraged by oceanographers because tides have little to do with these giant waves.
