Chile is a hotspot for earthquakes because the Nazca plate, a tectonic plate which moves eastwards with a rate of 6.6 cm per year, collides with the South American plate off the Chilean coast. The Nazca plate is submerged below the South American plate, and the pressure building up between the two plates is eventually released in the form of an earthquake. The strongest earthquake ever recorded by modern instruments was a 9.5-magnitude quake on May 22, 1960, which was centered offshore in southern Chile, where it set off a huge tsunami.
After being hit by the planet’s largest-ever recorded earthquake back in 1960, Chile developed strict anti-seismic building codes. Despite this, an 8.8-magnitude earthquake in 2010 wreaked destruction in southern and central parts of the country. More than 500 people were killed by the quake and the tsunami that followed. More than 200,000 homes were flattened. Things had to change again. Building codes were updated so structures could better withstand seismic waves. Strong columns and weak beams meant buildings would have a better chance of swaying with the tremors and avoiding collapse. Pressure was also exerted on planners for any new buildings to be constructed further from the sea.
Also, having learned from the past, better early warning systems are now in place. The National Seismological Centre in Chile functions around the clock since the government invested in a network of sensors throughout the country to record seismic activity. If there is going to be a big one, they’ll be alerted. Chile survived a big quake with relatively few casualties because it was ready for it. For many years now, local groups around the country have been familiarizing themselves with disaster preparedness plans, practicing countless earthquake drills and running through evacuation routes time and time again. The result? More than one million people were evacuated from coastal areas in a matter of hours, escaping the tsunami waves, some of which were 15 feet high in the region of Coquimbo.
Sources:
Earthquake in Chile (nasa.gov)
Seismic Monitor - Recent earthquakes on a world map and much more. (iris.edu)
Great post. Chile has similar seismic activity to my country, Nepal, with its history of severe earthquakes and need for earthquake standard building codes. Nepal however, does not have tsunamis, since it is a land-locked country. Nepal is also working to bring building standards up and raise awareness and teach people how to survive in earthquakes.
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