When a second earthquake is stronger than the first one, the first one is then considered a pre-quake. The stronger one is never considered an aftershock.
What a coincidence I was in Changwon, South Korea last week... and I will be back in Korea this Friday... hope it settles down. I was in Sasebo in April when the deadly Kumamoto quakes went off earlier this year!
Gyeongju is in the southern part of South Korea. Last weekend’s nuke test was in the northern part of North Korea, about 400 miles away.
The two locations are separated by the waters of the Sea of Japan.
We had quakes of that magnitude several times per day when I was at Clark AB during the Pinatubo eruption.
Gyeongju?
Do I really have to post the jokes?
Best wishes for all in the zone.