Chinese scientists have concluded that the 3.4 magnitude earthquake recorded on Saturday near the Democratic People's Republic of Korea's most recent nuclear test site was "natural".

"The incident was not a nuclear explosion, but had the characteristics of a natural quake," the China Earthquake Networks Center said late Saturday in a statement released online.

The earthquake took place around 4:30 pm near the area of Kilju in the northeastern DPRK, just around 6 kilometers from the Punggye-ri facility where the country held its latest test.

After the incident, the center quickly organized seismological bureaus and geological institutions to evaluate the situation, it said. The center previously issued a notice saying it suspected another test because the epicenter was located on the surface.

Seismologists from the Chinese Academy of Sciences and the University of California Santa Cruz also published a joint report on Saturday that said tests had shown the quake "clearly falls in the natural phenomena category" and was similar to the last natural earthquake in the region, which was recorded in December 2004.

A 3.4 magnitude quake would be much smaller than the quakes caused by previous DPRK nuclear tests, the report said. The weakest generated a 4.3 magnitude quake, while the strongest, this month, resulted in a 6.3 magnitude quake.

Saturday's earthquake is likely to be a "delayed collapse earthquake", the joint report said, without elaborating on the cause of the quake.

The Republic of Korea's weather agency also assessed the quake as natural, The Associated Press reported on Sunday.

The report said the analysis of seismic waves and the lack of sound waves clearly showed the quake was not caused by an artificial explosion, citing an unnamed weather agency official from the ROK.

DPRK conducted its sixth and most powerful nuclear test to date on Sept 3. The official Korean Central News Agency claimed it was a hydrogen bomb.

The test prompted global condemnation, leading the United Nations Security Council to unanimously adopt new sanctions that include restricting the DPRK's oil shipments.

"What the concerned parties should do now is to strictly and comprehensively implement UN Security Council resolutions and make positive efforts to resolve the issue through dialogue," Chinese Foreign Ministry spokesperson Lu Kang said at a news briefing on Friday.

zhangzhihao@chinadaily.com.cn

(China Daily 09/25/2017 page3)