The magnitude 8.8 earthquake struck at 3:34 A.M. on February 27, 2010, with an epicenter 200 miles southwest of Santiago, and a focus 22 miles below the surface of the Pacific Ocean. A 300 to 375 mile stretch of the fault had ruptured, and caused the earthquake. This fracture was caused by the stress brought on by the convergence between the Nazca and the South American Plates, and the fracture had a secondary effect of lifting a portion of seabed in the Pacific Ocean, causing a tsunami. All these events together resulted in about 500 deaths and nearly 400,000 homes destroyed.
The movement of the Nazca and the South American Plates caused this earthquake. The Nazca Plate subducts under the South American Plate, and this collision between the two causes friction to build up. Once the force of the subducting plate is enough to break the friction between the two plates, the fault ruptures, releasing all the energy that causes the earthquakes. In this case, it was a longer stretch of the fault that had ruptured, and it was fairly deep under the surface. This indicates that there was a very large amount of energy built up by the plates, which resulted in a particularly devastating earthquake.
According to the article, there were officials in the Chilean National Emergency Office and the navy’s Hydrographic and Oceanographic Service who were given indications of the tsunamis that resulted in from the earthquake. Despite the signs given to them by their geological studies, they did not warn the cities of these tsunami warnings and failed to evacuate people from the coastal cities. It was revealed in February 2013 that they tried to hide the fact that they ignored the warnings they had. As such, they were charged with negligence, and a seismologist mandated that these people would undergo additional training. The people charged were either sentenced to probation or they would pay a collective 235 million pesos to the 104 families of victims from the tsunami. We see that while the earthquake may have been hard to predict, the tsunami that followed had clear geological signs of coming, and they were simply ignored. View More »