Earthquake with magnitude of Mwp 6.9 on date 22-08-2021 and time 23:33:21 (Italy) in region South Georgia & the South Sandwich Is. [Sea]

A magnitude Mwp 6.9 earthquake occured in region: South Georgia & the South Sandwich Is. [Sea], on

  • 22-08-2021 21:33:21 (UTC)
  • 22-08-2021 23:33:21 (UTC +02:00) Italian time
  • 22-08-2021 19:33:21 (UTC -02:00) local time in the region of the earthquake (Atlantic/South_Georgia)

and geographic coordinates (lat, lon) -60.237, -24.831 at 7 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 updated as more data become available. See http://shakemap.ingv.it for additional information. The black star indicates the epicenter. The triangles show the accelerometric and velocimetric stations used in the calculation, colored according to the recorded shaking.

Intensity Shakemap

Intensity Shakemap

This map shows the distribution of instrumental intensities. The intensity is derived through an empirical law that correlates the recorded values of actual ground shaking, e.g., acceleration and velocity, with the macroseismic intensity for Italian earthquakes, as reported in the Italian Macroseismic Database (DBMI15, https://doi.org/10.13127/cpti/cpti15.3).
Peak ground acceleration Shakemap

Peak ground acceleration Shakemap

This map shows the distribution of peak ground acceleration expressed as percent 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 earthquake resentment in the area, expressed in terms of intensity on the MCS scale (Mercalli-Cancani-Sieberg). Intensities are determined using data from questionnaires collected on the website http://www.hsit.it. The intensities shown are determined considering all the reports received from each municipality, and are all the more reliable the greater the number of questionnaires. The collected data are subjected to an automatic statistical filter, but are not checked individually. In particular, intensities greater than or equal to the VI degree of the MCS or EMS scale require on-site verification by specialized personnel. The black star is the epicenter of the earthquake that occurred. This map is updated every time citizens fill out new questionnaires. The number of questionnaires processed to obtain this map, the date and time of the last update are shown at the top right.
Locations history
Type Magnitude Date and Time (UTC) Latitude Longitude Depth (km) Published time (UTC) Author Location ID
Reviewed
Rev200
Mwp 6.9 2021-08-22
21:33:21
-60.237 -24.831 7 2021-08-22
22:02:12
Sala Sismica INGV-Roma 94515591
Reviewed
Rev100
mb 5.8
Mwp 6.9
Mwpd 7.0
2021-08-22
21:33:21
-60.2367 -24.8307 7 2021-08-22
21:52:26
Sala Sismica INGV-Roma 94515301
Preferred location and magnitude until now.
Origin information

Origin

Field Value
Time (UTC) 2021-08-22 21:33:21
Latitude -60.2370
Longitude -24.8310
Depth (km) 7 ± 75 (from location)
Evaluation mode of Origin manual
Evaluation status of Origin reviewed
Version 200 -> SURVEY-INGV
Event type earthquake
Origin ID 94515591

Uncertainty

Field Value
Preferred uncertainty description horizontal uncertainty
Semi-major axis of confidence ellipse (meter)
Semi-minor axis of confidence ellipse (meter)
Azimuth of major axis of confidence ellipse. Measured clockwise from South-North direction at epicenter (gradi)
Circular confidence region, given by single value of horizontal uncertainty (meter) 21084
Confidence level of the uncertainty (%) 68

Quality

Field Value
Largest azimuthal gap in station distribution as seen from epicenter (degree) 67
Number of associated phases, regardless of their use for origin computation 1
Number of defining phases 1
RMS of the travel time residuals of the arrivals used for the origin computation (sec) 1.643
Epicentral distance of station closest to the epicenter (degree)
Epicentral distance of station farthest from the epicenter (degree)
Number of stations at which the event was observed 0
Number of stations from which data was used for origin computation 0
Magnitudes information

Mwpd:7

Field Value
Value 7
Uncertainty 0.1
Num. used stations 58
Type of magnitude Mwpd
Reference to an origin 94515301
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-22 21:52:26

Mwp:6.9

Field Value
Value 6.9
Uncertainty 0.2
Num. used stations 56
Type of magnitude Mwp
Reference to an origin 94515301
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-22 21:52:26

Mwp:6.9

Field Value
Value 6.9
Uncertainty 0.2
Num. used stations
Type of magnitude Mwp
Reference to an origin 94515591
Agency INGV
Autore Sala Sismica INGV-Roma
Time of creation (UTC) 2021-08-22 22:02:12

mb:5.8

Field Value
Value 5.8
Uncertainty 0.1
Num. used stations 64
Type of magnitude mb
Reference to an origin 94515301
Agency INGV
Autore early-est_ee1.1.9
Time of creation (UTC) 2021-08-22 21:52:26
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