Earthquake with magnitude of Mwp 6.0 on date 18-08-2021 and time 23:50:08 (Italy) in region South Georgia & the South Sandwich Is. [Sea]

A magnitude Mwp 6.0 earthquake occured in region: South Georgia & the South Sandwich Is. [Sea], on

  • 18-08-2021 21:50:08 (UTC)
  • 18-08-2021 23:50:08 (UTC +02:00) Italian time
  • 18-08-2021 19:50:08 (UTC -02:00) local time in the region of the earthquake (Atlantic/South_Georgia)

and geographic coordinates (lat, lon) -59.477, -26.471 at 126 km depth.

The earthquake was located by: Sala Sismica INGV-Roma.

Search earthquakes: Any within 30 km radius

The values of hypocentral coordinates and magnitude may be revised at a later time as more information becomes available.

Municipalities within 20 km from the epicenter

No Italian municipalities within 20 km distance.

Municipalities with at least 50000 inhabitants

No Italian municipalities within 100 km from the epicenter with at least 50000 inhabitants.

Recent and historical seismicity
Seismic hazard
Shakemap

These three maps show the results of the analysis using the software ShakeMap designed to provide the level of ground shaking experienced in a region using the data recorded by seismometers and strong motion instruments and seismological information regarding the attenuation of the wavefield with distance and the site characteristics. The Shakemaps are determined for research purposes to provide fast estimates of the level of ground shaking produced by the earthquake. The maps are calculated automatically and adjourned progressively as more data become available. See http://shakemap.rm.ingv.it/ for additional information.

The red star indicates the epicenter. The red triangles show the stations of the INGV Italian National Seismic Network and the blue triangles those of the Nationa Accelerometric Network of the Dipartimento della Protezione Civile.

Intensity Shakemap

Intensity Shakemap

This map shows the distribution of the istrumentally derived intensities. To this purpose, it is used a conversion relation between ground acceleration and velocity, and the Mercalli Modificata (MMI - Modified Mercalli Intensity) scale. In general, the Mercalli intensity scale relies on the effects that the ground shaking produces as reported by an observer.
Peak ground acceleration Shakemap

Peak ground acceleration Shakemap

This map shows This map shows the distribution of peak ground acceleration expressed as per cent of the acceleration of gravity (i.e., g = 9.81 m/s²).
Peak velocity Shakemap

Peak velocity Shakemap

This map shows the distribution of peak ground velocities expressed in cm/s.
Felt maps
Preliminary map of the earthquake effects from the web questionnaire

Preliminary map of the earthquake effects from the web questionnaire

This map shows the distribution of the effects of the earthquake on the territory in terms of the MCS (Mercalli-Cancani-Sieberg) intensity scale. The intensities are determined using the data provided in the questionnaire (http://www.haisentitoilterremoto.it/) that are analysed using robust statistical techniques since they are not verified individually. Specifically, the assignment of MCS intensities greater or equal the VI degree of the MCS scale require opportune in situ verification by professional experts. The purple start shows the epicenter. This map is prepared every so often that the population fill in new questionnaires. The number of questionnaires used to determine the map and the date and time of the last adjournment are shown in the upper right part of the panel.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev100
mb 5.3
Mwp 6.0

Mwpd 6.1
2021-08-18
21:50:08
-59.4773 -26.4714 126 2021-08-18
22:09:51
Sala Sismica INGV-Roma 94346741
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-18 21:50:08
Latitude -59.4773
Longitude -26.4714
Depth (km) 126 (from location)
Evaluation mode of Origin automatic
Evaluation status of Origin reviewed
Version 100 -> SURVEY-INGV-A
Event type earthquake
Origin ID 94346741

Uncertainty

Field Value
Preferred uncertainty description uncertainty ellipse
Semi-major axis of confidence ellipse (meter) 13127
Semi-minor axis of confidence ellipse (meter) 5651
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi) 192
Circular confidence region, given by single value of horizontal uncertainty (meter) 11313.3
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 68.3993
Number of associated phases, regardless of their use for origin computation 51
Number of defining phases 51
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 0.842891
Epicentral distance of station closest to the epicenter (degree) 7.53022
Epicentral distance of station farthest from the epicenter (degree) 99.04534
Number of stations at which the event was observed 51
Number of stations from which data was used for origin computation 51
Magnitudes information

Mwpd:6.1

Field Value
Value 6.1
Uncertainty 0.1
Num. used stations 7
Type of magnitude Mwpd
Reference to an origin 94346741
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-18 22:09:51

Mwp:6

Field Value
Value 6
Uncertainty 0.1
Num. used stations 8
Type of magnitude Mwp
Reference to an origin 94346741
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-18 22:09:51

mb:5.3

Field Value
Value 5.3
Uncertainty 0.2
Num. used stations 46
Type of magnitude mb
Reference to an origin 94346741
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-18 22:09:51
Picking and Arrival
SCNL Time Uncertainty Polarity Evaluation_mode Phase Azimuth Distance Takeoff_angle Residual Weight
II.WRAB.BHZ.00 2021-08-18T22:03:33.35 10.0 positive automatic P 162 99.0453 -0.367286 0.0414046
IU.MBWA.BHZ.00 2021-08-18T22:03:14.55 10.0 negative automatic P 149 94.7373 0.315024 0.0637269
IU.TEIG.BHZ.00 2021-08-18T22:03:10.47 10.0 negative automatic P 304 94.1626 -1.102 0.0685993
AU.QLP.BHZ. 2021-08-18T22:03:09.62 10.0 positive automatic P 172 93.5925 0.640544 0.0656617
AU.WRKA.BHZ.00 2021-08-18T22:03:06.45 10.0 positive automatic P 157 92.9584 0.317305 0.0655866
AU.ARMA.BHZ. 2021-08-18T22:02:53.72 10.0 positive automatic P 178 90.0866 0.79346 0.0924209
G.TAM.BHZ.00 2021-08-18T22:02:36.15 10.0 positive automatic P 29 86.3624 0.822501 0.120652
AU.HTT.BHZ. 2021-08-18T22:02:35.45 10.0 positive automatic P 168 86.302 0.534046 0.118304
AU.MORW.BHZ. 2021-08-18T22:02:34.60 10.0 positive automatic P 148 86.1953 0.278083 0
G.CAN.BHZ.00 2021-08-18T22:02:29.65 10.0 positive automatic P 176 85.1256 0.552034 0.114122
NZ.OUZ.HHZ.10 2021-08-18T22:02:23.59 10.0 positive automatic P 196 83.8477 1.02965 0.139595
AU.MILA.BHZ.00 2021-08-18T22:02:21.43 10.0 positive automatic P 176 83.3962 1.04 0.14473
IU.NWAO.BHZ.00 2021-08-18T22:02:17.37 10.0 positive automatic P 150 82.8358 -0.0620197 0.144369
AU.TOO.BHZ.00 2021-08-18T22:02:17.50 10.0 positive automatic P 174 82.7193 0.632009 0.152346
IU.SNZO.BHZ.00 2021-08-18T22:01:51.62 10.0 positive automatic P 196 77.7041 1.71378 0.197067
II.TAU.BHZ.00 2021-08-18T22:01:49.37 10.0 positive automatic P 175 77.4814 0.698087 0.194645
NZ.KHZ.HHZ.10 2021-08-18T22:01:45.68 10.0 positive automatic P 195 76.7745 0.969656 0.199722
II.MBAR.BHZ.00 2021-08-18T22:01:28.35 10.0 positive automatic P 61 73.4926 2.21072 0.230025
IU.OTAV.BHZ.00 2021-08-18T22:01:17.07 10.0 positive automatic P 304 71.9828 -0.506749 0.264083
GT.DBIC.BHZ.00 2021-08-18T22:00:53.85 10.0 positive automatic P 23 68.3485 -0.997154 0.304223
II.NNA.BHZ.00 2021-08-18T22:00:02.02 10.0 positive automatic P 300 60.2757 -0.311827 0.329088
GT.LPAZ.BHZ.00 2021-08-18T21:59:09.30 10.0 positive automatic P 307 52.7104 -0.210471 0.528578
IU.TSUM.BHZ.00 2021-08-18T21:58:56.97 10.0 positive automatic P 58 51.0937 0.058528 0.548672
CX.MNMCX.BHZ. 2021-08-18T21:58:54.50 10.0 positive automatic P 304 50.7607 -0.102155 0.23276
IU.CASY.BHZ.00 2021-08-18T21:58:50.42 10.0 positive automatic P 159 50.2646 -0.0638228 0.536892
GE.WIN.BHZ. 2021-08-18T21:58:32.95 10.0 positive automatic P 59 47.8962 0.20217 0.550364
GT.BOSA.BHZ.00 2021-08-18T21:58:20.68 10.0 negative automatic P 72 46.47 -0.937165 0.627733
AF.ALKP.BHZ. 2021-08-18T21:58:01.14 10.0 positive automatic P 70 43.9176 -0.295895 0.673655
C.GO03.BHZ. 2021-08-18T21:57:59.35 10.0 negative automatic P 297 43.6055 0.47384 0.671389
BL.PMNB.HHZ. 2021-08-18T21:57:57.07 10.0 positive automatic P 332 43.4062 -0.250062 0.70314
AF.GRHM.BHZ. 2021-08-18T21:57:56.27 10.0 negative automatic P 77 43.1887 0.75838 0.703824
GT.VNDA.BHZ.00 2021-08-18T21:57:53.55 10.0 positive automatic P 183 42.9062 0.392046 0.0977362
C1.VA04.BHZ. 2021-08-18T21:57:52.73 10.0 negative automatic P 283 42.6518 1.62039 0.705426
IU.SBA.BHZ.00 2021-08-18T21:57:50.12 10.0 positive automatic P 184 42.4312 0.807263 0.223091
IU.LCO.BHZ.00 2021-08-18T21:57:50.92 10.0 positive automatic P 296 42.6034 -0.166678 0.553077
C.GO04.BHZ. 2021-08-18T21:57:43.45 10.0 positive automatic P 295 41.6628 0.0183548 0.303576
II.SUR.BHZ.00 2021-08-18T21:57:40.17 10.0 negative automatic P 70 41.2096 0.493726 0.724147
C1.CO02.BHZ. 2021-08-18T21:57:37.48 10.0 positive automatic P 294 40.8875 0.539879 0.326293
GT.CPUP.BHZ.00 2021-08-18T21:57:23.48 10.0 positive automatic P 314 39.3895 -0.927859 0.664222
G.PEL.BHZ.00 2021-08-18T21:57:22.80 10.0 positive automatic P 292 39.1185 0.547948 0.746609
C.GO05.BHZ. 2021-08-18T21:57:14.45 10.0 negative automatic P 289 38.1856 0.0903229 0.792118
C1.BO02.BHZ. 2021-08-18T21:57:11.20 10.0 negative automatic P 291 37.814 -0.189127 0.809308
AU.MAW.BHZ. 2021-08-18T21:57:02.70 10.0 positive automatic P 141 36.9947 -1.6207 0.698298
C.GO06.BHZ. 2021-08-18T21:56:40.88 10.0 positive automatic P 285 34.341 -1.00676 0.860402
GT.PLCA.BHZ.00 2021-08-18T21:56:29.80 10.0 positive automatic P 285 33.0083 -0.507624 0.802242
C1.LL02.BHZ. 2021-08-18T21:56:19.40 10.0 positive automatic P 280 31.8209 -0.425453 0.947164
G.COYC.BHZ.00 2021-08-18T21:56:06.70 10.0 negative automatic P 277 30.2437 0.756565 0.947271
C.GO10.BHZ. 2021-08-18T21:55:18.73 10.0 positive automatic P 265 25.0007 -0.512953 0.963855
C1.MG02.BHZ. 2021-08-18T21:55:11.35 10.0 positive automatic P 267 24.2782 -1.23503 0.952381
II.EFI.BHZ.00 2021-08-18T21:54:22.62 10.0 positive automatic P 280 19.253 0.956128 0.952381
II.HOPE.BHZ.00 2021-08-18T21:51:54.37 10.0 negative automatic P 309 7.5302 0.176752 0.909091
TDMT - Time Domain Moment Tensor
Fault Plane solutions in the area
Download
Type Description Link
QuakeML - small Event, Origin, FocalMechanism Download
QuakeML - full Event, Origin, FocalMechanism, Amplitude, Arrival, Pick, Station Magnitude Download