A 7.4 earthquake in Fukushima surprises Korea

A 7.4 earthquake in Fukushima surprises Korea. November. 23, 2016 07:22. sya@donga.com,kyungeun@donga.com. A magnitude 7.4 earthquake hit off the shore of Fukushima Prefecture in Japan at 5:59 a.m. on Tuesday. Japanese media reported that the quake injured 13 people as of the Tuesday afternoon. Thousands of residents evacuated the affected area and some 260 schools in Kanto were closed temporarily.

Korea, which was surprised at the quake in Gyeongju in September, stayed alert. However, the Korea Meteorological Administration said that the earthquake in Japan has no impact on the Korean Peninsula. “As the earthquake that hit the eastern region of Japan had no direct damage to Korea at all such as a tsunami or a tremor as it was physically distant from the Korean Peninsula,” the agency said. “Though a seismic wave was detected in Korea, the tremor was so minimal that it could not be translated into the Richter scale.”

Some citizens expressed concerns, however. When Korea’s most powerful earthquake and aftershocks struck Gyeongju on Sept. 12, some analysts said that it was due to the earthquake that hit eastern Japan in 2011, also known as “Great East Japan Earthquake.” Again, people posted online about the quake in japan, saying it could have an impact on the geological structure of the Korean Peninsula.

In response, experts said, “The quake is much weaker than the Great East Japan Earthquake.” They said it is different from the one in 2011.

“It is hard to conclude that the earthquake has no impact on the Korean Peninsula at all as earthquakes in general have extensive impacts on geological structures in general,” said Hong Tae-gyeong, an Earth Systems Science professor at Yonsei University. “The quake is estimated to be around 6.9 to 7.4 on the Richter scale and its energy was only one-thousandth of that of the earthquake in eastern Japan in 2011, which means that the impact is minimal, if any.”

“The length of the fault that caused the quake in 2011 was up to 400 kilometers and the origin of the recent quake is exactly on the fault,” said Ji Heon-cheol, a senior researcher at Geoscience Research Center of the Korea Institute of Geoscience and Mineral Resources. “While the quake in 2011 was caused by the shrinking earth crust, the recent one was triggered during the expansion of the condensed seismic pressure.” He indicated that this means the pressure is unlikely to increase.