The most severe earthquake in history, which changed the geography of the earth

Dr Abdul Waheed Mastoi
On May 22, 1960, the most severe earthquake in history occurred in Chile, a country located in the south of Latin America.
At that time, it was 3:11 pm that for about 10 minutes, earthquake tremors were felt in an area of ​​1,000 km out of 5,000 km of the Pacific coastline.
The earthquake measured 9.5 on the Richter scale and released as much energy from the ground as 20,000 bombs dropped on Hiroshima.
The resulting tsunami created waves as high as 25 meters in the ocean. These waves also caused widespread destruction where they buried many coastal towns.
According to the United States Geological Survey (USGS), more than 1,600 people were killed, 3,000 injured and 2 million people displaced in this earthquake in the south of the country.
Chile’s geography changed. There were towns that were submerged and areas were seen that were raised several meters. A volcano erupted and several rivers changed their course.
The fury of the earthquake was felt all over the world. Earthquake waves shook the planet.
At the same time as the earth was shaking, a tsunami was generated in the sea, which also engulfed the western coasts of the United States, Hawaii, the Philippines and Japan, causing a total of more than 200 deaths.
Even after 62 years, the earthquake in Chile is remembered as the country’s worst disaster.
However, the disaster also left valuable lessons for science and disaster prevention.
Since May 21, strong earthquakes with a magnitude greater than eight have been occurring off the coast of Concepcion, Chile, but the next day there was an even bigger one.
About 160 kilometers off the coast of the city of Valdivia, the Nazca tectonic plate moved about 30 meters below the South American plate.
A case where two contiguous plates slide over each other is known as a ‘subduction zone’.
The friction between the two plates released centuries of stored energy and resulted in the greatest damage in the region between Valdivia and Puerto Montt.
Most of the destruction was caused by tsunami waves along the coast. Cities like Puerto, Saavedra were completely destroyed and other places like Corral suffered severe damage.
In Valdivia, the ground sank up to 2.7 meters. Several rivers changed their course around the city. Some plains became marshlands and thousands of hectares of crop fields and pastures were lost.
Daniel Melnik, a researcher and geologist at the Institute of Earth Sciences at the Australasian University in Chile, told BBC Mundo that “it completely changed the landscape of the Earth.”
“You can still see telephone poles, fence wires and submerged roads in the middle of the river around Valdivia,” Melnik says.
Over time, the creation of wetlands also attracted new types of plants and bird species that were not previously seen in the region.
The sinking of the land at Mavlin and Chiloi was also a ‘brutal affair’, Melnick points out.
On the contrary, in other places, instead of sinking, the land rose, i.e., the surface became higher. For example, Guafu Island rose four meters and Guamblin Island rose 5.6 meters.
On May 24, two days after the earthquake, the Puhoe volcano erupted, sending steam and ash up to 6,000 meters high.
The eruption of this volcano continued for several weeks and was caused by the movement of plates that caused the continent to spread.
Melnick says it was “like you popped the cork out of a bottle of wine.”
Cumulative effects
The earthquake caused a tidal wave that spread across the Pacific Ocean. The friction between the tectonic plates shook the ocean to a depth of 3000 meters.
The biggest impact was in Chile, where the tsunami in some areas raised the shape of the bay, but the waves from the tsunami reached the other side of the planet.
15 hours after the earthquake in Hilo, Hawaii, a tsunami struck, killing 61 people and causing severe damage. Waves higher than 10 meters were seen there.
In the Philippines, 32 people were killed by the tsunami waves, while Easter Island and California were also damaged.
Some 17,000 kilometers outside of Chile, the biggest disaster occurred in Japan, where 5.5-meter-high waves reached the Honshu region 22 hours after the quake, destroying 1,600 homes and killing 138 people.