1960 Great Chilean Earthquake (Valdivia Earthquake)

(Photo of  1960 Chilean earthquake in the city of Valdivia (globalvoices, 2010))

 

Before the earthquake:

    A day prior to the devastating events of the Valdivia earthquake in Chile several foreshocks shook the island estimated to be around 8.1 in magnitude (Britannica, 2022). The science of seismology at the time had not acheievd its breakthough quite yet so the foreshocks were thought to be the full extent of the earthquakes, though the foreshocks did cause damage in cities like Concepcion it was not nearly as powerful as what was to come.

 

 The Earthquake:

   At approximately 3:31pm on May 22,1960 an earthquake agreed upon by experts to have been a magnitude of around 9.5 occurred 100 miles off the coast of the country of Chile. The source of the earthquake extended approximately 600 miles across the Nazca Plate. The Nazca plate is an oceanic plate being subducted by the South American plate (a continental plate) as shown in figure 1 (Britannica, 2022).

(Fig. 1 Map of Chile coast and affected plates (Britannica, 2022))

    The Earthquake itself was named after one of the cities most affected by it, the city of Valdivia. Notable subsidence occurred throughout the coast in many major cities causing significant damage to infrastructure and farmland. In Valdivia nearly half of all the buildings in and around the city were completely destroyed by the subsidence and shaking. However, the shaking was not responsible for most of the loss of life and injuries. Fifteen minutes after the shaking began to cease a tsunami, created by the shifting of the seafloor due to the subducting plates, hit most of the Chilean coast. The waves reached approximately 80 feet in height and hit cities such as Lebu and Puerto Aisen as they were geographically parallel to the event (Britannica, 2022). The combination of the earthquake and tsunami caused an estimated $4.8 billion (adjusted for inflation in 2020) in damages throughout Chile and an estimated 2 million people were left without homes or shelter. The death toll of these events in Chile are still not well known but experts project around 1,655 people lost their lives in this event, including those of other countries affected. (NatGeo, 2022). Chile wasn’t the only country affected by the tsunami either Hawaii, Australia and even Japan saw waves reach their shores between 35-16 feet tall causing destruction and fatalities there as well as shown in figure 2. A video of some news coverage from the time as well as a retrospective look at the coverage by CBS is also linked below.

(Fig. 2 Tsunami spread from 1960 Valdivia Earthquake(Britannica, 2022))

(CBS retrospective on the 1960 Valdivia Earthquake coverage (CBS, 2010))

The Aftermath

    As if the earthquake and tsunami weren't enough for the devastated nation of Chile, two days later the Cordon Caulle Volcano erupted after 40 years of dormancy. The Volcanos sudden activity is attributed to the seismic activity prior but due to a lack of seismological instruments at the time nothing is certain. After the earthquake Chile formed a committee to oversee the and solve the problems caused by the Valdivia earthquake as well as future disasters. This committee would later be called the ONEMI which is an acronym in Spanish which stands for: Ministry of of Interior National Emergency Office (Argouse, 2006). The Subsidence of the earthquake also caused large swaths of farmland to become permanently submerged and created what is now the Carlos Anwandter Nature Sanctuary due to the growth of a plant known as the Egeria densa which created a hospitable aquatic environment that allowed Black Necked Swans to thrive (San Martín Padovani et al., 1993).

 

Work Cited:

Argouse, A. (2006). María Eugenia Petit-Breuilh Sepúlveda, naturaleza y desastres en Hispanoamérica. la visión de los indígenas. Nuevo Mundo Mundos Nuevos. https://doi.org/10.4000/nuevomundo.2935

Chile: The legacy of the 1960 earthquake in Valdivia. Global Voices. (2010, February 28). Retrieved September 11, 2022, from https://globalvoices.org/2010/02/28/chile-the-legacy-of-the-1960-earthquake-in-valdivia/ 

Encyclopædia Britannica, inc. (n.d.). Chile earthquake of 1960. Encyclopædia Britannica. Retrieved September 11, 2022, from https://www.britannica.com/event/Chile-earthquake-of-1960

National geographic. (n.d.). May 22, 1960 CE: Valdivia earthquake strikes Chile. National Geographic Society. Retrieved September 11, 2022, from https://education.nationalgeographic.org/resource/valdivia-earthquake-strikes-chile

San Martín Padovani Cristina, Medina Jaramillo, R., Ojeda Nempu, P., & Ramírez García Carlos. (1993). La Biodiversidad Vegetacional del Santuario de la Naturaleza del "Río Cruces" (Valdivia, Chile). Acta Botanica Malacitana, 18, 259–279. https://doi.org/10.24310/abm.v18i.8996