Spate of tremors has Interior Ministry on earthquake alert
Published On : Wed, Mar 26th, 2014
Since a March 16 earthquake that rocked the northern city of Iquique, seismologists have documented over 300 aftershocks and tremors.
In response to increased seismic activity and concerns following an earthquake in the Tarapacá Region, seismologists will ramp up monitoring activities in the region as government officials meet with local authorities to ensure the preparedness of communities in Northern Chile.
The March 16 quake, which registered 6.7 on the Richter scale, left over 22,000 residents in the coastal city of Iquique without electricity and over 100,000 were evacuated from their homes following a precautionary tsunami warning, though the wave never materialized.
On Wednesday, Interior Minister Rodrigo Peñalillo asked his undersecretary, Mahmud Aleuy, and the director of the National Emergency Service (ONEMI), Ricardo Toro, to review preparation, response and evacuation measures in Iquique.
Peñalillo has also announced the injection of more than US$6 million to fortify ONEMI’s preventative and operational capacity and speed up its installation of 77 seismic monitoring devices throughout the country, called accelerographs, originally planned for 2015.
Diana Comte, a seismologist at the National Seismology Center (CSN) and professor at the Universidad de Chile, told The Santiago Times that she will be joining several teams on Thursday to install 11 portable monitoring stations around the most active areas.
However, Comte added that the high number of tremors experienced in the past week was not in and of itself significant, but rather that several of them had registered higher than six on the Richter scale.
“The truth is, it is of no importance if there have been 300 or 350 or 280 tremors,” Comte said. “The majority of those quakes were small, except for the four that registered higher than six and maybe a fifth one at 5.9, in a very short period of time.”
Comte added that although the events were statistically out of the ordinary, they did not necessarily indicate the imminence of a large earthquake in the near future.
“Capacity to predict earthquakes is still very low at the local, regional and global level,” she said “There will be an earthquake that affects the north of Chile, but scientists can’t say when or exactly where.”
According to John Bellini, a geophysicist at the United States Geological Survey in Colorado, the reason recent quakes in the region have caught the geological community’s attention is because of something called a seismic gap.
The term refers to an area along a fault known to produce large earthquakes, but that has been inactive for an unusually long time. The last time Chile’s northern coast saw a large earthquake was in 1877, which registered 8.5 in magnitude, resulted in a tsunami and claimed over 2,000 lives.
Although the 1877 quake was also preceded by a similar flurry of quakes like the ones occurring now, Bellini said it isn’t necessarily cause for concern.
“There is no general pattern for every large earthquake,” Bellini said “Every area that has a major earthquake has a period of quiet for many decades after, even hundreds of years.”
Despite the uncertainty of earthquakes, the CSN’s deputy director, Mario Pardo, told La Tercera on Monday that “the possibility of a larger earthquake cannot be ruled out.” That same day, he also spoke with NBC, in which he stressed that the CSN is doing everything it can to provide update information to the public and emergency responders.
“We are working with all our authorities and they now have immediate access to our information in real time. We just want to make sure people are prepared,” Pardo said.
But Pardo did lend some level of certainty, though ominous, to the unpredictable nature of earthquakes.
“A big earthquake could strike in a number of years or it could strike sooner,” Pardo said “The only thing we can be certain of is that it will strike.”
Located along the Pacific Ocean’s “ring of fire” — a horseshoe shaped series of oceanic trenches conducive to a large number of earthquakes and volcanic eruptions — Chile is one of the most seismically active countries in the world.
In 1960, the largest earthquake ever recorded, magnitude 9.5, struck near Lumaco in the Araucanía Region, killing thousands. It is remembered as the Valdivia Earthquake, after the disaster’s most affected city, located in the Los Ríos Region.
Copyright 2014 – The Santiago Times