A wall in a residential area in Buan, North Jeolla Province, shows a significant crack, Thursday, following a 4.8 magnitude earthquake that struck the area, Wednesday. Yonhap

A 4.8 magnitude earthquake rattled the southwestern county of Buan in North Jeolla Province, Wednesday, prompting residents to question the safety of their regions. Despite the growing concerns, there is currently no digitalized official map available to quickly assess earthquake risks across different areas.

The recent earthquake in Buan, which marks the strongest tremor detected on the Korean Peninsula and its surrounding waters this year, has raised serious safety concerns among residents.

North Jeolla Province, typically unaccustomed to seismic activity, experienced its first earthquake exceeding magnitude 4.

Damage reports have also surged. As of 10:30 p.m. on Thursday, a total of 401 reports of damage to facilities were received, according to the Central Disaster and Safety Countermeasures Headquarters.

In the wake of the unexpected quake and its aftermath, the public is increasingly questioning the safety of their regions.

However, the government is not expected to consider creating a detailed earthquake risk map until after 2026, following the completion of the second phase of a tomography study that began in 2017.

According to the interior ministry, Friday, the only official map available is the national earthquake risk map released in 2013.

The national earthquake risk map / Courtesy of National Fire Agency

This map only indicates the frequency of past earthquakes by region, using contours based on historical data and does not provide detailed risk assessments for specific areas.

Moreover, while earthquake risk coefficients have been established for each region to guide seismic design standards, these coefficients have not been updated in over a decade.

An official at the interior ministry said the earthquake risk for each region does not significantly change within five to 10 years, and a committee of experts reviews potential revisions every five years.

Last year, the committee reviewed the existing data and concluded that it remains valid and can continue to be used without modification.

Beyond the national earthquake risk map, the government has embarked on a comprehensive investigation of fault structure lines across the Korean Peninsula, running from 2017 to 2036.

This initiative aims to identify active faults in Korea and is spearheaded by five major organizations, including the interior ministry and the Korea Meteorological Administration (KMA).

Having completed the first phase in the South Gyeongsang region, the survey has now moved to its second phase, covering the metropolitan areas such as Incheon and Gyeonggi Province and Chungcheong areas.

The interior ministry anticipates that by 2026, enough data will have been collected to create a digitized earthquake risk map. This map would allow the public to easily assess earthquake risks in their regions, much like existing flood risk maps.

The investigation focuses on various types of faults — surface faults by the interior ministry, deep faults by the KMA and marine faults by the Ministry of Oceans and Fisheries.

The aim is to compile these data into a comprehensive map to help the public better understand fault and earthquake risks in their areas.

An official at the interior ministry also explained that the results of the investigation will be recognized as official data by both the government and academia. These findings will be crucial for shaping various earthquake policies, including decisions on whether to update the national map for earthquake risks.