The Atlantic Ocean has been hit by a series of strong earthquakes, but the Pacific Tsunami Warning Center in Ewa Beach, Hawaii, which tracks tsunami threats in the Atlantic as well, reports that there is no tsunami threat to Puerto Rico, the US Virgin Islands, the British Virgin Islands, or anywhere else along the US East Coast and the Caribbean at this time.
The most recent earthquake, a magnitude 5.0, struck north of Ascension Island this afternoon at 12:43 p.m. ET. The earthquake occurred halfway between New York City and Cape Town, as well as halfway between Brazil and Lagos.
The earthquake occurred along the Mid Atlantic Ridge, which separates the South American Plate from the African Plate, in a seismically active area of the Romanche Fracture Zone. The two plates are moving apart in this part of the world, causing earthquakes as they split above the ridge.
An even stronger 6.6 earthquake struck east of the South Sandwich Islands yesterday morning, followed by a weaker but still powerful 5.0 earthquake last night. The Tsunami Warning Center issued a statement following the 6.6 earthquakes, stating that “based on all available data… there is no tsunami threat to Puerto Rico, the US Virgin Islands, or the British Virgin Islands from this earthquake.”
The Tsunami Warning Center issued an additional bulletin covering the United States East Coast, the Gulf of Mexico, and eastern Canada, adding that “based on earthquake information and historic tsunami records, the earthquake is not expected to generate a tsunami.” Yesterday’s stronger earthquake occurred in the South Atlantic, where the South American Plate is moving away from the Antarctic Plate.
These plates are based on Plate Tectonics, a scientific theory that describes the large-scale motion of the plates that make up the Earth’s lithosphere. Scientists believe that tectonic processes began on Earth between 3.3 and 3.5 billion years ago, based on the concept of continental drift, which was developed in the early twentieth century. The gradual movement of continents across the Earth’s surface over geological time is known as continental drift.
Tsunamis are massive waves caused by undersea earthquakes or volcanic eruptions. Tsunami waves do not grow dramatically in height as they travel deeper into the ocean. However, as the waves travel inland, they build up to greater and greater heights as the ocean’s depth decreases.
The speed of tsunami waves, according to the National Ocean Service, is determined by ocean depth rather than the distance from the source of the wave. Tsunami waves can travel at the same speed as jet planes over deep water, only slowing down when they reach shallow water.
While tsunamis are frequently referred to as tidal waves, oceanographers discourage using this term because tides have little to do with these massive waves.