Another earthquake hits Puerto Rico, with expected aftershock
Puerto Rico has faced aftershock days following a 6.4 magnitude earthquake on Tuesday and was struck with a magnitude 5.9 tremor on Saturday.
Puerto Rico was shaken by another major earthquake early Saturday, which came after a major earthquake struck the island's southern coast on Tuesday.
The latest seismic activity had closed its epicenter off the coast of Guanica, a town on the island's southern coast. The 5.9-magnitude earthquake - initially believed to be a 6.0-magnitude earthquake - shook many of the buildings and left concrete island roads scattered about. According to the Puerto Rico Seismic Network (PRSN), Puerto Rico has been racked up since Tuesday's 6.4-magnitude earthquake with at least a 3.0-magnitude 45 aftershock that killed one person and nine others were injured.
Due to the latest earthquake, nearly one million Puerto Ricans were without electricity, hundreds lacked clean water, and more than 2,000 people were living in shelters. The Puerto Rico Electric Power Authority said the power was almost completely restored following Saturday's earthquake, with 93 percent of the island now claiming power.
Nevertheless, Saturday's tremors are expected to face an already severe situation. Thousands of homes and school buses have collapsed, adding to the already widespread damage, including the destruction of Punta Ventana, the famous natural landmark.
Puerto Rico was hit by Hurricane Maria in 2017 after President Donald Trump declared a state of emergency on the island late Tuesday. The announcement would free up federal disaster funds to aid with recovery, but local officials worried that aid was too slow to make a difference.These pictures from downtown Ponce, Puerto Rico was just sent to me. This, I'm told, is new damage caused by the 6.0 magnitude eatheuake that happened a short time ago. pic.twitter.com/JU8ZE9vTlk— David Begnaud (@DavidBegnaud) January 11, 2020
“FEMA is a very bureaucratic agency and it is very slow moving. Slowly that we are still waiting for federal money from Maria, ”Daniel Hernández, generation director for the Electric Power Authority of Puerto Rico, told the Associated Press.
For now, residents of the island are trying to protect themselves once again from a natural disaster that has devastated the island's infrastructure. And unfortunately, there may be more aftershock hits on the island.
PRSN chief Victor Huirefano said Saturday's seismic activity is likely to trigger aftershocks.
"This is about to reactivate a volatile situation," the Associated Press said, adding Huerfano. "It is a complex area."
Earthquakes are difficult to predict - but Puerto Rico may face more in the coming days
It is nearly ten years since it overtook Puerto Rico, the day in 2010 when a massive 7.0-magnitude hit hit Haiti. However, experts have said that this time is just a coincidence, and while historical and real-time seismometer data can be revealed. Expected seismic trends, predicting accurate seismic activity to save lives are usually a much more difficult proposition.
According to the US Geological Survey (USGS), Puerto Rico has experienced 139 seismic movements above a magnitude of 3.0 since early December. Seismologist Lucy Jones suggested on Twitter that they were all part of a sustained seismic event. The frequency of these events, and Puerto Rico's earthquake susceptibility, stems from the way the island lies along the meeting points of the South American, Caribbean, and North American plates:
Puerto Rico has a long history of quakes because it sits on a complicated plate boundary. The small Caribbean plate pushes over the South American plate's oceanic crust east of PR. North of PR, the Caribbean plate slides past North America. Puerto Rico gets squeezed between. pic.twitter.com/iHenv2XL4O— Dr. Lucy Jones (@DrLucyJones) January 7, 2020
As of yesterday, the seismic forecast for the USGS region predicted a decreasing number of aftershocks after the major earthquake on Tuesday.Puerto Rico is caught between two subduction zones. The current quake swarm is off the southwest coast, past of the adjustment between the two big faults. Sort of like Northridge 1994 was on a small fault to adjust for the bend in the San Andreas fault. pic.twitter.com/AsJDAwZbLv— Dr. Lucy Jones (@DrLucyJones) January 7, 2020
After Saturday's earthquake, the USGS gave Puerto Rico a chance of about 3 percent, experiencing another 6.4 magnitude, which almost eclipsed on Saturday. However, the organization warned that a "high probability" of magnitude-3.0 was aftershock or could be higher next week.
As Umair Irfan of Vox has explained, it is difficult to give more detailed forecasts than those in earthquake areas:
It is difficult to predict when an earthquake will occur, because the forces it produces are slowly over a vast area, but are rapidly distributed over a narrow area. It is amazing that armies built over continents in millions of years can beat cities in minutes.
Earthquake forecasting requires high-resolution measurements over the course of decades, at a deeper level, if not coupled with sophisticated simulations. And even then, it is unlikely to produce a lead time of one hour. So ultimately there are too many variables to play and very few tools to analyze them in a meaningful way.
Some research suggests that foreboding can lead to a large earthquake, but it is difficult to distinguish them from the hundreds of small earthquakes that occur regularly.
Despite being involved in this difficulty, USGS and PRSN officials have been busy this weekend to monitor seismic activity and to help forecast the hanger already on the resale island south of Puerto Rico Temporary seismometers are being installed along the coast. In the meantime, thousands will live in shelters, waiting for concrete assurances that it is safe to return and begin rebuilding.