Information message about a strong earthquakes in Yunnan Province, China, May 21, 2021

An earthquake (strong at the epicenter on the SHSI-17 scale) with M = 5.5 occurred on May 21, 2021 at 13:21 GMT (16:21 Moscow time) in Yunnan Province, China. The second shock (at the epicenter, destructive on the SHSI-17 scale) with a magnitude of M = 6.1 occurred 27 minutes later at 13:48 GMT (16:48 Moscow time).

Parameters of the earthquake have been determined in the Alert Service (AS) of Information Processing Center (IPC) of Geophysical Survey of RAS in Obninsk with station data obtained from digital and analog seismic stations of Russia, countries of CIS and from abroad. Alert message on the first earthquake has been delivered in 14 min after registration to the Ministry of Emergency of the Russian Federation (EMERCOM). Alert message on the second earthquake has been delivered in 14 min.

Preliminary processing for the first earthquake has been done with data from 21 stations, accurate processing - with data from 42. Preliminary processing for the second earthquake has been done with data from 21 stations, accurate processing - with data from 42.

The red markers on the map are the epicenters of earthquakes located in Yunnan Province, China, at a depth of 10 km. The epicenter of the first earthquake was 11 km N-NW of Dali and 265 km W-NW of Kunming, the epicenter of the second shock was 15 km N-NW of the first.
Time in origin (GMT) Latitude, degree Longitude, degree Depth, km Stations number Ms/N mb/N I0 (calculated) GAP Center
1 13:21:25.9 25.71 100.15 10.0 21 5.5/15 6.5-7 GS RAS(Preliminary [1])
Federal research center, Geophysical survey of Russian Academy of Sciences
2 13:21:27.1 25.7 100.06 10.0 181 Mw 5.3 29 CSEM(Verified [1])
European - Mediterranean seismological center
3 13:21:26.8 25.71 100.06 10.0 97 Mw 5.3/20 5.2/99 33 NEIC(Verified [1])
National Earthquakes Information Center of US Geological Service
4 13:48:37.0 25.8 100.11 10.0 53 6.1/31 5.9/33 8.5-9 79 GS RAS(Verified [2])
Federal research center, Geophysical survey of Russian Academy of Sciences
5 13:48:36.8 25.89 100.22 10.0 22 5.8/17 7-7.5 GS RAS(Preliminary [2])
Federal research center, Geophysical survey of Russian Academy of Sciences
6 13:48:37.9 25.74 100.05 11.8 367 Mw 6.1 18 CSEM(Verified [2])
European - Mediterranean seismological center
7 13:48:37.3 25.76 100.01 10.0 102 Mw 6.1/34 5.6/99 21 NEIC(Verified [2])
National Earthquakes Information Center of US Geological Service
8 13:21:26.0 25.68 100.16 10.0 42 5.5/26 6.5-7 73 GS RAS(Verified [1])
Federal research center, Geophysical survey of Russian Academy of Sciences