In each case, the South Korean authorities put the magnitude higher than 5.4--

September 12, 2016, magnitude 5.4

https://earthquake.usgs.gov/earthquakes/eventpage/us10006p1f#executive

November 15, 2017, magnitude 5.4

https://earthquake.usgs.gov/earthquakes/eventpage/us2000bnrs#executive

https://www.washingtonpost.com/world/asia_pacific/55-magnitude-quake-hits-off-south-koreas-coast/2017/11/15/da6df366-c9c8-11e7-b506-8a10ed11ecf5_story.html?utm_term=.44f8ee94ba5e

: http://m.koreaherald.com/view.php?ud=20171115000742#cb
: "[Breaking] Powerful earthquakes strike Pohang; nuclear
: plant not affected
: By Korea Herald

: A quake with the magnitude of 5.5 hits Pohang, at 2:29 p.m. on
: Wednesday, followed by an aftershock of 5.4. Tremors were
: felt across the nation..."
: Published : Nov 15, 2017 - 14:37 (12:37 a.m. EST)

: I'm working on a post entitled "Does tonight's biggest
: Guam earthquake in three years and some other things signal
: November 15-16 is a "Day of Burning"?"

: --and just saw the EMSC bulletin about these two quakes on the
: Eastern coast of South Korea: Mainshock 12:30 a.m. EST
: 11/15/2017
: Magnitude 5.4
:
: https://earthquake.usgs.gov/earthquakes/eventpage/us2000bnrs#executive

: Aftershock 12:33 a.m. EST 11/15/2017
: Magnitude 3.6
: https://m.emsc.eu/earthquake/earthquake.php?evid=630319

: There is no report yet about it at Korea Times online but soon
: will be, I see these interesting eadlines there:
: http://www.koreatimesus.com/american-nabbed-while-trying-to-enter-n-korea/

:
: http://www.koreatimesus.com/n-korean-soldier-defects-to-south-suffers-gunshot-from-north/

: Today's quake in South Korea is the strongest since September
: 12, 2016, here's my comments of November 6 about it: