A moderately strong earthquake struck the Mid Atlantic Ridge during the overnight hours but there is no risk of tsunami to the U.S. East Coast at this time. According to USGS, at 9:41 pm last night, a magnitude 5.1 earthquake struck the Mid Atlantic Ridge in the North Atlantic from a depth of 10 km. This is a seismically active area; over the last 30 days, USGS reports there were 7 earthquakes rated as a magnitude 4.5 or greater; the strongest was a magnitude 6.6 earthquake on March 21.

While the National Weather Service’s Tsunami Warning Center is monitoring for any tsunami threat, none exists.

The  central Mid Atlantic Ridge  separates the South American Plate from the African Plate. In this part of the world, the two plates are moving apart, triggering earthquakes as they split above the ridge.

These plates are based on the scientific theory of Plate Tectonics, which describes the large-scale motion of plates making up the Earth’s lithosphere. Scientists believe tectonic processes began on Earth between 3.3 and 3.5 billion years, building upon the concept of continental drift, a scientific concept developed in the early part of the 20th century. Continental drift is the gradual movement of the continents across the Earth’s surface through geological times.

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. 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, this name is discouraged by oceanographers because tides have little to do with these giant waves.