A 5.4 magnitude earthquake hit the city of Pohang in North Gyeongsang Province at 2:29 p.m. Wednesday, injuring more than 50 people and causing damage to buildings, roads and public facilities.
It is the second most powerful earthquake in Korean history following the 5.8 magnitude quake in Gyeongju last year.
According to the Korea Meteorological Administration (KMA), the quake was centered in an area some 9 kilometers north of Pohang on the southeastern coast around 9 kilometers underground.
This was shallower than the Gyeongju earthquake, which occurred at a depth of 15 kilometers, and explains why the tremor was felt more extensively this time nationwide, including in Seoul which is some 300 kilometers away from Pohang.
Two foreshocks preceded the quake and were followed by numerous aftershocks, which experts say may continue for several months.
Over a thousand cases of damaged buildings have been reported, mostly involving broken roofs. The majority of the injured suffered wounds from falling objects or building debris.
Fortunately key industrial facilities and nuclear power plants were unaffected, while steel mills, auto factories and semiconductor firms were also left unscathed from the tremor.
The city of Pohang estimated tentative losses of some 7 billion won as of Thursday.
The government also announced it will take steps to declare Pohang as a special disaster zone and provide four billion won in special grants.
Meanwhile, the nationwide college entrance examination scheduled for Thursday has been postponed by one week considering students’ safety. Inspections are also under way at test sites.
The cause of the latest quake is believed to be due to faults that have been activated since the devastating earthquake that struck Japan in 2011.
Some 450 active faults are currently known to exist in South Korea, with the Yangsan Fault line connecting Gyeongju, Yangsan and Busan known as the largest in scale.
But some speculate that, given the major earthquakes reported last and this year, there may be hidden active faults that are not yet known.
The fact that key infrastructure was left undamaged is being attributed to improved quake-resistant design measures.
However, the latest earthquake has revealed a lack of quake preparations at schools. In fact, only 24 percent of school facilities in North Gyeongsang Province are built to resist tremors, a modest improvement from 18.7 percent last year.
In the aftermath, calls are being made to prepare against aftershocks and help with the emotional wellbeing of the victims.