
Puerto Rico remains seismically active, with 24 earthquakes reported by the USGS in the last 24 hours and 447 in the last month; while the island has been busy shaking, there are no reports of damage or injuries and there is no threat of tsunami at this time.
Of the 24 earthquakes to be measured in Puerto Rico over the last 24 hours, the strongest four were a 3.9, a 3.6, a 3.2, and a 3.1 magnitude event. While people in Puerto Rico are reporting feeling shaking from these quakes, the earthquakes haven’t been strong enough to produce any issues, including damage, injuries, and tsunami.
A 4.3 that struck yesterday did prompt the National Weather Service Pacific Tsunami Warning Center in Honolulu, Hawaii to issue a bulletin. In their bulletin, they reported that “based on all available data, there is no tsunami threat to Puerto Rico, the U.S. Virgin Islands, or the British Virgin Islands from this earthquake.” However, they added, “people may have experienced shaking from the earthquake.” The center in Honolulu is responsible for issuing bulletins about tsunami threats to the U.S. East and Gulf Coasts.
While 2 earthquakes struck north of the Virgin Islands today, most have been centered around southwestern Puerto Rico. Because of the location of those southwestern earthquakes, it is likely the latest quakes are aftershocks from a seismic event that unfolded in 2020. In January 2020, a 6.4 created extensive damage in Puerto Rico, including widespread power failures across much of the island. An earthquake swarm started there in December 2019 and the seismic unrest has continued since.
These earthquakes are occurring near the northern edge of the Caribbean Plate, a mostly oceanic tectonic plate underlying Central America and the Caribbean Sea off of the north coast of South America. The Caribbean Plate borders the North American Plate, the South American Plate, the Nazca Plate, and the Cocos Plate. The borders of these plates are home to ongoing seismic activity, including frequent earthquakes, occasional tsunamis, and sometimes even volcanic eruptions.